2011 Microchip Technology Inc. DS39960C
PIC18F87K22 Family
Data Sheet
64/80-Pin, High-Performance,
1-Mbit Enhanced Flash Microcontrollers
with 12-Bit A/D and
nanoWatt XLP Technology
DS39960C-page 2 2011 Microchip Technology Inc.
Information contained in this publication regarding device
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Trademarks
The Microchip name and logo, the Microchip logo, dsPIC,
KEELOQ, KEELOQ logo, MPLAB, PIC, PICmicro, PICSTART,
PIC32 logo, rfPIC and UNI/O are registered trademarks of
Microchip Technology Incorporated in the U.S.A. and other
countries.
FilterLab, Hampshire, HI-TECH C, Linear Active Thermistor,
MXDEV, MXLAB, SEEVAL and The Embedded Control
Solutions Company are registered trademarks of Microchip
Technology Incorporated in the U.S.A.
Analog-for-the-Digital Age, Application Maestro, CodeGuard,
dsPICDEM, dsPICDEM.net, dsPICworks, dsSPEAK, ECAN,
ECONOMONITOR, FanSense, HI-TIDE, In-Circuit Serial
Programming, ICSP, Mindi, MiWi, MPASM, MPLAB Certified
logo, MPLIB, MPLINK, mTouch, Omniscient Code
Generation, PICC, PICC-18, PICDEM, PICDEM.net, PICkit,
PICtail, REAL ICE, rfLAB, Select Mode, Total Endurance,
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SQTP is a service mark of Microchip Technology Incorporated
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All other trademarks mentioned herein are property of their
respective companies.
© 2011, Microchip Technology Incorporated, Printed in the
U.S.A., All Rights Reserved.
Printed on recycled paper.
ISBN: 1-60932-956-3
Note the following details of the code protection feature on Microch ip devices:
• Microchip products meet the specification contained in their particular Microchip Data Sheet.
• Microchip believes that its family of products is one of the most secure families of its kind on the market today, when used in the
intended manner and under normal conditions.
• There are dishonest and possibly illegal methods used to breach the code protection feature. All of these methods, to our
knowledge, require using the Microchip products in a manner outside the operating specifications contained in Microchip’s Data
Sheets. Most likely, the person doing so is engaged in theft of intellectual property.
• Microchip is willing to work with the customer who is concerned about the integrity of their code.
• Neither Microchip nor any other semiconductor manufacturer can guarantee the security of their code. Code protection does not
mean that we are guaranteeing the product as “unbreakable.”
Code protection is constantly evolving. We at Microchip are committed to continuously improving the code protection features of our
products. Attempts to break Microchip’s code protection feature may be a violation of the Digital Millennium Copyright Act. If such acts
allow unauthorized access to your software or other copyrighted work, you may have a right to sue for relief under that Act.
Microchip received ISO/TS-16949:2002 certification for its worldwide
headquarters, design and wafer fabrication facilities in Chandler and
Tempe, Arizona; Gresham, Oregon and design centers in California
and India. The Company’s quality system processes and procedures
are for its PIC® MCUs and dsPIC® DSCs, KEELOQ® code hopping
devices, Serial EEPROMs, microperiph erals, nonvolatile memory and
analog products. In addition, Microchip’s quality system for the design
and manufacture of development systems is ISO 9001:2000 certified.
2011 Microchip Technology Inc. DS39960C-page 3
PIC18F87K22 FAMILY
Low-Power Features:
• Power-Managed modes:
- Run: CPU on, peripherals on
- Idle: CPU off, peripherals on
- Sleep: CPU off, peripherals off
• Two-Speed Oscillator Start-up
• Fail-Safe Clock Monitor
• Power-Saving Peripheral Module Disable (PMD)
• Ultra Low-Power Wake-up
• Fast Wake-up, 2 s Typical
• Low-Power WDT, 300 nA Typical
• Ultra Low 50 nA Input Leakage
• Run mode Currents Down to Very Low 5.5 mA,
Typical
• Idle mode Currents Down to Very Low 2.2 mA,
Typical
• Sleep mode Currents Down to Very Low 20 nA,
Typical
• RTCC Current Downs to Very Low 700 nA,
Typical
S pecial Microcontroller Features:
• Operating Voltage Range: 1.8V to 5.5V
• On-Chip 3.3V Regulator
• Operating Speed up to 64 MHz
• Up to 128 Kbytes On-Chip Flash Program
Memory
• Data EEPROM of 1,024 Bytes
• 4K x 8 General Purpose Registers (SRAM)
• 10,000 Erase/Write Cycle Flash Program
Memory, Typical
• 1,000,000 Erase/write Cycle Data EEPROM
Memory, Typical
• Flash Retention 40 Years, Minimum
• Three Internal Oscillators: LF-INTRC (31 kHz),
MF-INTOSC (500 kHz) and HF-INTOSC
(16 MHz)
• Self-Programmable under Software Control
• Priority Levels for Interrupts
• 8 x 8 Single-Cycle Hardware Multiplier
• Extended Watchdog Timer (WDT):
- Programmable period from 4 ms to 4,194s
(about 70 minutes)
• In-Circuit Serial Programming™ (ICSP™) via
Two Pins
• In-Circuit Debug via Two Pins
• Programmable:
-BOR
-LVD
Device
Program Memory Dat a Memory
I/O 12-Bit
A/D
(ch)
CCP/
ECCP
(PWM)
MSSP
EUSART
Comparators
Timers
8/16-Bit
External Bus
CTMU
RTCC
Flash
(bytes) # Single-Word
Instructions SRAM
(bytes) EEPROM
(bytes) SPI Master
I2C™
PIC18F65K22 32K 16,383 2K 1K 53 16 5/3 2 Y Y 2 3 4/4 N Y Y
PIC18F66K22 64K 32,768 4K 1K 53 16 7/3 2Y Y 236/5NYY
PIC18F67K22 128K 65,536 4K 1K 53 16 7/3 2Y Y 236/5NYY
PIC18F85K22 32K 16,383 2K 1K 69 24 5/3 2 Y Y 2 3 4/4 Y Y Y
PIC18F86K22 64K 32,768 4K 1K 69 24 7/3 2Y Y 236/5YYY
PIC18F87K22 128K 65,536 4K 1K 69 24 7/3 2Y Y 236/5YYY
64/80-Pin, High-Performance, 1-Mbit Enhanced Flash MCUs
with 12-Bit A/D and nanoWatt XLP Technology
PIC18F87K22 FAMILY
DS39960C-page 4 2011 Microchip Technology Inc.
Peripheral Highlights:
• Up to Ten CCP/ECCP modules:
- Up to seven Capture/Compare/PWM (CCP)
modules
- Three Enhanced Capture/Compare/PWM
(ECCP) modules
• Up to Eleven 8/16-Bit Timer/Counter modules:
- Timer0 – 8/16-bit timer/counter with 8-bit
programmable prescaler
- Timer1,3 – 16-bit timer/counter
- Timer2,4,6,8 – 8-bit timer/counter
- Timer5,7 – 16-bit timer/counter for 64k and
128k parts
- Timer10,12 – 8-bit timer/counter for 64k and
128k parts
• Three Analog Comparators
• Configurable Reference Clock Output
• Hardware Real-Time Clock and Calendar (RTCC)
module with Clock, Calendar and Alarm Functions
• Charge Time Measurement Unit (CTMU):
- Capacitance measurement for mTouch™
sensing solution
- Time measurement with 1 ns typical
resolution
- Integrated temperature sensor
• High-Current Sink/Source 25 mA/25 mA (PORTB
and PORTC)
• Up to Four External Interrupts
• Two Master Synchronous Serial Port (MSSP)
modules:
- 3/4-wire SPI (supports all four SPI modes)
-I
2C™ Master and Slave modes
• Two Enhanced Addressable USART modules:
- LIN/J2602 support
- Auto-Baud Detect (ABD)
• 12-Bit A/D Converter with up to 24 Channels:
- Auto-acquisition and Sleep operation
- Differential input mode of operation
• Integrated Voltage Reference
2011 Microchip Technology Inc. DS39960C-page 5
PIC18F87K22 FAMILY
Pin Diagrams – PIC18F6XK22
1
2
3
4
5
6
7
8
9
10
11
12
13
14
38
37
36
35
34
33
50 49
17 18 19 20 21 22 23 24 25 26
RE2/CS/P2B/CCP10(2)
RE3/P3C/CCP9(2)/REF0
RE4/P3B/CCP8
RE5/P1C/CCP7
RE6/P1B/CCP6
RE7/ECCP2/P2A
RD0/PSP0/CTPLS
VDD
VSS
RD1/PSP1/T5CKI/T7G
RD2/PSP2
RD3/PSP3
RD4/PSP4/SDO2
RD5/PSP5/SDI2/SDA2
RD6/PSP6/SCK2/SCL2
RD7/PSP7/SS2
RE1/WR/P2C
RE0/RD/P2D
RG0/ECCP3/P3A
RG1/TX2/CK2/AN19/C3OUT
RG2/RX2/DT2/AN18/C3INA
RG3/CCP4/AN17/P3D/C3INB
MCLR/RG5
RG4/RTCC/T7CKI(2)/T5G/CCP5/AN16/P1D/C3INC
VSS
VDDCORE/VCAP
RF7/AN5/SS1
RF6/AN11/C1INA
RF5/AN10/CVREF/C1INB
RF4/AN9/C2INA
RF3/AN8/C2INB/CTMUI
RF2/AN7/C1OUT
RB0/INT0/FLT0
RB1/INT1
RB2/INT2/CTED1
RB3/INT3/CTED2/ECCP2(1)/PA2
RB4/KBI0
RB5/KBI1/T3CKI/T1G
RB6/KBI2/PGC
VSS
OSC2/CLKO/RA6
OSC1/CLKI/RA7
VDD
RB7/KBI3/PGD
RC4/SDI1/SDA1
RC3/SCK1/SCL1
RC2/ECCP1/P1A
ENVREG
RF1/AN6/C2OUT/CTDIN
AVDD
AVSS
RA3/AN3/VREF+
RA2/AN2/VREF-
RA1/AN1
RA0/AN0/ULPWU
VSS
VDD
RA4/T0CKI
RA5/AN4/T1CKI/T3G/HLVDIN
RC1/SOSCI/ECCP2(1)/P2A
RC0/SOSCO/SCLKI
RC7/RX1/DT1
RC6/TX1/CK1
RC5/SDO1
15
16
31
40
39
27 28 29 30 32
48
47
46
45
44
43
42
41
54 53 52 5158 57 56 5560 5964 63 62 61
64-Pin TQFP, QFN
PIC18F65K22
PIC18F66K22
PIC18F67K22
Note 1: The ECCP2 pin placement depends on the CCP2MX Configuration bit setting and whether the device is
in Microcontroller or Extended Microcontroller mode.
2: Not available on the PIC18F65K22 and PIC18F85K22 devices.
PIC18F87K22 FAMILY
DS39960C-page 6 2011 Microchip Technology Inc.
Pin Diagrams – PIC18F8XK22
3
4
5
6
7
8
9
10
11
12
13
14
15
16
48
47
46
45
44
43
42
41
40
39
64 63 62 61
21 22 23 24 25 26 27 28 29 30 31 32
RE2/P2B/CCP10(2)/CS/AD10
RE3/P3C/CCP9(2)(3)/REF0/AD11
RE4/P3B/CCP8(3)/AD12
RE5/P1C/CCP7(3)/AD13
RE6/P1B/CCP6(3)/AD14
RE7/ECCP2/P2A/AD15
RD0/CTPLS/AD0
VDD
VSS
RD1/T5CKI/T7G/AD1
RD2/PSP2/AD2
RD3/PSP3/AD3
RD4/SDO2/PSP4/AD4
RD5/SDI2/SDA2/PSP5/AD5
RD6/SCK2/SCL2/PSP6/AD6
RD7/SS2/PSP7/AD7
RE1/P2C/WR/AD9
RE0/P2D/RD/AD8
RG0/ECCP3/P3A
RG1/TX2/CK2/AN19/C3OUT
RG2/RX2/DT2/AN18/C3INA
RG3/CCP4/AN17/P3D/C3INB
MCLR/RG5
RG4/RTCC/T7CKI(2)/T5G/CCP5/AN16/P1D/C3INC
VSS
VDDCORE/VCAP
RF7/AN5/SS1
RB0/INT0/FLT0
RB1/INT1
RB2/INT2/CTED1
RB3/INT3/CTED2/ECCP2(1)/P2A
RB4/KBI0
RB5/KBI1/T3CKI/T1G
RB6/KBI2/PGC
VSS
OSC2/CLKO/RA6
OSC1/CLKI/RA7
VDD
RB7/KBI3/PGD
RC4/SDI1/SDA1
RC3/SCK1/SCL1
RC2/ECCP1/P1A
ENVREG
RF1/AN6/C2OUT/CTDIN
AVDD
AVSS
RA3/AN3/VREF+
RA2/AN2/VREF-
RA1/AN1
RA0/AN0/ULPWU
VSS
VDD
RA4/T0CKI
RA5/AN4/T1CKI/T3G/HLVDIN
RC1/SOSC/ECCP2/P2A
RC0/SOSCO/SCKLI
RC7/RX1/DT1
RC6/TX1/CK1
RC5/SDO1
RJ0/ALE
RJ1/OE
RH1/AN22/A17
RH0/AN23/A16
1
2
RH2/AN21/A18
RH3/AN20/A19
17
18
RH7/CCP6(3)/P1B/AN15
RH6/CCP7(3)/P1C/AN14/C1INC
RH5/CCP8(3)/P3B/AN13/C2IND
RH4/CCP9(2)(3)/P3C/AN12/C2INC
RJ5/CE
RJ4/BA0
37
RJ7/UB
RJ6/LB
50
49
RJ2/WRL
RJ3/WRH
19
20
33 34 35 36 38
58
57
56
55
54
53
52
51
60
59
68 67 66 6572 71 70 6974 7378 77 76 757980
80-Pin TQFP
RF5/AN10/C1INB
RF4/AN9/C2INA
RF3/AN8/C2INB/CTMUI
RF2/AN7/C1OUT
RF6/AN11/C1INA
PIC18F85K22
PIC18F86K22
PIC18F87K22
Note 1: The ECCP2 pin placement depends on the CCP2MX Configuration bit setting and whether the device is
in Microcontroller or Extended Microcontroller mode.
2: Not available on the PIC18F65K22 and PIC18F85K22 devices.
3: The CC6, CCP7, CCP8 and CCP9 pin placement depends on the setting of the ECCPMX Configuration
bit (CONFIG3H<1>).
2011 Microchip Technology Inc. DS39960C-page 7
PIC18F87K22 FAMILY
Table of Contents
1.0 Device Overview .......................................................................................................................................................................... 9
2.0 Guidelines for Getting Started with PIC18FXXKXX Microcontrollers ......................................................................................... 37
3.0 Oscillator Configurations ............................................................................................................................................................ 43
4.0 Power-Managed Modes ............................................................................................................................................................. 57
5.0 Reset .......................................................................................................................................................................................... 73
6.0 Memory Organization ................................................................................................................................................................. 87
7.0 Flash Program Memory............................................................................................................................................................ 111
8.0 External Memory Bus............................................................................................................................................................... 121
9.0 Data EEPROM Memory ........................................................................................................................................................... 133
10.0 8 x 8 Hardware Multiplier.......................................................................................................................................................... 139
11.0 Interrupts .................................................................................................................................................................................. 141
12.0 I/O Ports ................................................................................................................................................................................... 165
13.0 Timer0 Module ......................................................................................................................................................................... 193
14.0 Timer1 Module ......................................................................................................................................................................... 197
15.0 Timer2 Module ......................................................................................................................................................................... 209
16.0 Timer3/5/7 Modules.................................................................................................................................................................. 211
17.0 Timer4/6/8/10/12 Modules........................................................................................................................................................ 223
18.0 Real-Time Clock and Calendar (RTCC)................................................................................................................................... 227
19.0 Capture/Compare/PWM (CCP) Modules ................................................................................................................................. 245
20.0 Enhanced Capture/Compare/PWM (ECCP) Module................................................................................................................ 259
21.0 Master Synchronous Serial Port (MSSP) Module .................................................................................................................... 281
22.0 Enhanced Universal Synchronous Asynchronous Receiver Transmitter (EUSART) ............................................................... 327
23.0 12-Bit Analog-to-Digital Converter (A/D) Module ..................................................................................................................... 351
24.0 Comparator Module.................................................................................................................................................................. 367
25.0 Comparator Voltage Reference Module................................................................................................................................... 375
26.0 High/Low-Voltage Detect (HLVD)............................................................................................................................................. 379
27.0 Charge Time Measurement Unit (CTMU) ................................................................................................................................ 385
28.0 Special Features of the CPU.................................................................................................................................................... 403
29.0 Instruction Set Summary.......................................................................................................................................................... 431
30.0 Development Support............................................................................................................................................................... 481
31.0 Electrical Characteristics.......................................................................................................................................................... 485
32.0 Packaging Information.............................................................................................................................................................. 525
Appendix A: Revision History............................................................................................................................................................. 531
Appendix B: Migration From PIC18F87J11 and PIC18F8722 to PIC18F87K22................................................................................ 532
Index .................................................................................................................................................................................................. 533
The Microchip Web Site..................................................................................................................................................................... 545
Customer Change Notification Service .............................................................................................................................................. 545
Customer Support .............................................................................................................................................................................. 545
Reader Response .............................................................................................................................................................................. 546
Product Identification System ............................................................................................................................................................ 547
PIC18F87K22 FAMILY
DS39960C-page 8 2011 Microchip Technology Inc.
TO OUR VALUED CUSTOMERS
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2011 Microchip Technology Inc. DS39960C-page 9
PIC18F87K22 FAMILY
1.0 DEVICE OVERVIEW
This document contains device-specific information for
the following devices:
This family combines the traditional advantages of all
PIC18 microcontrollers – namely, high computational
performance and a rich feature set – with an extremely
competitive price point. These features make the
PIC18F87K22 family a logical choice for many
high-performance applications where price is a primary
consideration.
1.1 Core Features
1.1.1 nanoWatt TECHNOLOGY
All of the devices in the PIC18F87K22 family incorpo-
rate a range of features that can significantly reduce
power consumption during operation. Key items include:
•Alternate Run Modes: By clocking the controller
from the Timer1 source or the Internal RC oscilla-
tor, power consumption during code execution
can be reduced.
•Multiple Idle Modes: The controller can also run
with its CPU core disabled but the peripherals still
active. In these states, power consumption can be
reduced even further.
•On-the-Fly Mode Switching: The power-managed
modes are invoked by user code during operation,
allowing the user to incorporate power-saving ideas
into their application’s software design.
•nanoWatt XLP: An extra low-power Sleep, BOR,
RTCC and Watchdog Timer
1.1.2 OSCILLATOR OPTIONS AND
FEATURES
All of the devices in the PIC18F87K22 family offer
different oscillator options, allowing users a range of
choices in developing application hardware. These
include:
• External Resistor/Capacitor (RC); RA6 available
• External Resistor/Capacitor with Clock Out
(RCIO)
• Three External Clock modes:
- External Clock (EC); RA6 available
- External Clock with Clock Out (ECIO)
- External Crystal (XT, HS, LP)
• A Phase Lock Loop (PLL) frequency multiplier,
available to the external oscillator modes which
allows clock speeds of up to 64 MHz. PLL can
also be used with the internal oscillator.
• An internal oscillator block that provides a 16 MHz
clock (±2% accuracy) and an INTRC source
(approximately 31 kHz, stable over temperature
and VDD)
- Operates as HF-INTOSC or MF-INTOSC
when block selected for 16 MHz or 500 kHz
- Frees the two oscillator pins for use as
additional general purpose I/O
The internal oscillator block provides a stable reference
source that gives the family additional features for
robust operation:
•Fail-Safe Clock Monitor: This option constantly
monitors the main clock source against a reference
signal provided by the internal oscillator. If a clock
failure occurs, the controller is switched to the
internal oscillator, allowing for continued low-speed
operation or a safe application shutdown.
•Two-Speed S tart-up: This option allows the
internal oscillator to serve as the clock source
from Power-on Reset, or wake-up from Sleep
mode, until the primary clock source is available.
1.1.3 MEMORY OPTIONS
The PIC18F87K22 family provides ample room for
application code, from 32 Kbytes to 128 Kbytes of code
space. The Flash cells for program memory are rated
to last up to 10,000 erase/write cycles. Data retention
without refresh is conservatively estimated to be
greater than 40 years.
The Flash program memory is readable and writable.
During normal operation, the PIC18F87K22 family also
provides plenty of room for dynamic application data
with up to 3,862 bytes of data RAM.
1.1.4 EXTERNAL MEMORY BUS
Should 128 Kbytes of memory be inadequate for an
application, the 80-pin members of the PIC18F87K22
family have an External Memory Bus (EMB) enabling
the controller’s internal program counter to address a
memory space of up to 2 Mbytes. This is a level of data
access that few 8-bit devices can claim and enables:
• Using combinations of on-chip and external
memory of up to 2 Mbytes
• Using external Flash memory for reprogrammable
application code or large data tables
• Using external RAM devices for storing large
amounts of variable data
1.1.5 EXTENDED INSTRUCTION SET
The PIC18F87K22 family implements the optional
extension to the PIC18 instruction set, adding eight
new instructions and an Indexed Addressing mode.
Enabled as a device configuration option, the extension
has been specifically designed to optimize re-entrant
application code originally developed in high-level
languages, such as ‘C’.
• PIC18F65K22 • PIC18F85K22
• PIC18F66K22 • PIC18F86K22
• PIC18F67K22 • PIC18F87K22
PIC18F87K22 FAMILY
DS39960C-page 10 2011 Microchip Technology Inc.
1.1.6 EASY MIGRATION
All devices share the same rich set of peripherals
except that the devices with 32 Kbytes of program
memory (PIC18F65K22 and PIC18F85K22) have two
less CCPs and three less timers. This provides a
smooth migration path within the device family as
applications evolve and grow.
The consistent pinout scheme, used throughout the
entire family, also aids in migrating to the next larger
device. This is true when moving between the 64-pin
members, between the 80-pin members, or even
jumping from 64-pin to 80-pin devices.
All of the devices in the family share the same rich set
of peripherals, except for those with 32 Kbytes of
program memory (PIC18F65K22 and PIC18F85K22).
Those devices have two less CCPs and three less
timers.
The PIC18F87K22 family is also largely pin compatible
with other PIC18 families, such as the PIC18F8720 and
PIC18F8722 and the PIC18F85J11. This allows a new
dimension to the evolution of applications, allowing
developers to select different price points within
Microchip’s PIC18 portfolio, while maintaining a similar
feature set.
1.2 Other Speci al Features
•Communications: The PIC18F87K22 family
incorporates a range of serial communication
peripherals including two Enhanced USART, that
support LIN/J2602, and two Master SSP modules
capable of both SPI and I2C™ (Master and Slave)
modes of operation.
•CCP Modules: PIC18F87K22 family devices
incorporate up to seven Capture/Compare/PWM
(CCP) modules. Up to six different time bases can
be used to perform several different operations at
once.
•ECCP Modules: The PIC18F87K22 family has
three Enhanced CCP (ECCP) modules to
maximize flexibility in control applications:
- Up to eight different time bases for
performing several different operations
at once
- Up to four PWM outputs for each module, for
a total of 12 PWMs
- Other beneficial features, such as polarity
selection, programmable dead time,
auto-shutdown and restart, and Half-Bridge
and Full-Bridge Output modes
•12-Bit A/D Converter: The PIC18F87K22 family
has differential ADC. It incorporates program-
mable acquisition time, allowing for a channel to
be selected and a conversion to be initiated
without waiting for a sampling period, and thus,
reducing code overhead.
•Charge Time Measurement Unit (CTMU): The
CTMU is a flexible analog module that provides
accurate differential time measurement between
pulse sources, as well as asynchronous pulse
generation.
• Together with other on-chip analog modules, the
CTMU can precisely measure time, measure
capacitance or relative changes in capacitance, or
generate output pulses that are independent of
the system clock.
•LP W atch dog T im er (WDT): This enhanced
version incorporates a 22-bit prescaler, allowing
an extended time-out range that is stable across
operating voltage and temperature. See
Section 31.0 “Electrical Characteristics” for
time-out periods.
•Real-Time Clock and Calendar Module
(RTCC): The RTCC module is intended for appli-
cations requiring that accurate time be maintained
for extended periods of time with minimum to no
intervention from the CPU.
• The module is a 100-year clock and calendar with
automatic leap year detection. The range of the
clock is from 00:00:00 (midnight) on January 1,
2000 to 23:59:59 on December 31, 2099.
2011 Microchip Technology Inc. DS39960C-page 11
PIC18F87K22 FAMILY
1.3 Details on Individual Family
Members
Devices in the PIC18F87K22 family are available in
64-pin and 80-pin packages. Block diagrams for the
two groups are shown in Figure 1-1 and Figure 1-2.
The devices are differentiated from each other in these
ways:
• Flash Program Memory:
- PIC18FX5K22 (PIC18F65K22 and
PIC18F85K22) – 32 Kbytes
- PIC18FX6K22 (PIC18F66K22 and
PIC18F86K22) – 64 Kbytes
- PIC18FX7K22 (PIC18F67K22 and
PIC18F87K22) – 128 Kbytes
• Data RAM:
- All devices except PIC18FX5K22 – 4 Kbytes
- PIC18FX5K22 – 2 Kbytes
•I/O Ports:
- PIC18F6XK22 (64-pin devices) –
seven bidirectional ports
- PIC18F8XK22 (80-pin devices) –
nine bidirectional ports
• CCP modules:
- PIC18FX5K22 (PIC18F65K22 and
PIC18F85K22) – five CCP modules
- PIC18FX6K22 and PIC18FX7K22
(PIC18F66K22, PIC18F86K22,
PIC18F67K22, and PIC18F87K22) –
seven CCP modules
• Timer modules:
- PIC18FX5K22 (PIC18F65K22 and
PIC18F85K22) – Four 8-bit timer/counters
and four 16-bit timer/counters
- PIC18FX6K22 and PIC18FX7K22
(PIC18F66K22, PIC18F86K22,
PIC18F67K22, and PIC18F87K22) – six 8-bit
timer/counters and five 16-bit timer/counters
• A/D Channels:
- PIC18F6XK22 (64-pin devices) – 24 channels
- PIC18F8XK22 (80-pin devices) – 16 channels
All other features for devices in this family are identical.
These are summarized in Ta b l e 1 - 1 and Tab l e 1-2 .
The pinouts for all devices are listed in Tabl e 1 -3 and
Table 1-4.
PIC18F87K22 FAMILY
DS39960C-page 12 2011 Microchip Technology Inc.
TABLE 1-1: DEVICE FEATURES FOR THE PIC18F6XK22 (64-PIN DEVICES)
TABLE 1-2: DEVICE FEATURES FOR THE PIC18F8XK22 (80-PIN DEVICES)
Features PIC18F65K22 PIC18F66K22 PIC18F67K22
Operating Frequency DC – 64 MHz
Program Memory (Bytes) 32K 64K 128K
Program Memory (Instructions) 16,384 32,768 65,536
Data Memory (Bytes) 2K 4K 4K
Interrupt Sources 42 48
I/O Ports Ports A, B, C, D, E, F, G
Parallel Communications Parallel Slave Port (PSP)
Timers 8 11
Comparators 3
CTMU Yes
RTCC Yes
Capture/Compare/PWM (CCP) Modules 5 7 7
Enhanced CCP (ECCP) Modules 3
Serial Communications Two MSSPs and two Enhanced USARTs (EUSART)
12-Bit Analog-to-Digital Module 16 Input Channels
Resets (and Delays) POR, BOR, RESET Instruction, Stack Full, Stack Underflow, MCLR, WDT
(PWRT, OST)
Instruction Set 75 Instructions, 83 with Extended Instruction Set Enabled
Packages 64-Pin QFN, 64-Pin TQFP
Features PIC18F85K22 PIC18F86K22 PIC18F87K22
Operating Frequency DC – 64 MHz
Program Memory (Bytes) 32K 64K 128K
(Up to 2 Mbytes with Extended Memory)
Program Memory (Instructions) 16,384 32,768 65,536
Data Memory (Bytes) 2K 4K 4K
Interrupt Sources 42 48
I/O Ports Ports A, B, C, D, E, F, G, H, J
Parallel Communications Parallel Slave Port (PSP)
Timers 8 11
Comparators 3
CTMU Yes
RTCC Yes
Capture/Compare/PWM (CCP) Modules 5 7 7
Enhanced CCP (ECCP) Modules 3
Serial Communications Two MSSPs and 2 Enhanced USARTs (EUSART)
12-Bit Analog-to-Digital Module 24 Input Channels
Resets (and Delays) POR, BOR, RESET Instruction, Stack Full, Stack Underflow, MCLR, WDT
(PWRT, OST)
Instruction Set 75 Instructions, 83 with Extended Instruction Set Enabled
Packages 80-Pin TQFP
2011 Microchip Technology Inc. DS39960C-page 13
PIC18F87K22 FAMILY
FIGURE 1-1: PIC18F6X K22 (64-PIN) BLOCK DIAGRAM
Instruction
Decode and
Control
PORTA
Data Latch
Data Memory
(2/4 Kbytes)
Address Latch
Data Address<12>
12
Access
BSR FSR0
FSR1
FSR2
inc/dec
logic
Address
412 4
PCH PCL
PCLATH
8
31-Level Stack
Program Counter
PRODLPRODH
8 x 8 Multiply
8
BITOP
8
8
ALU<8>
Address Latch
Program Memory
Data Latch
20
8
8
Table Pointer<21>
inc/dec logic
21
8
Data Bus<8>
Table Latch
8
IR
12
3
PCLATU
PCU
Note 1: See Table 1-3 for I/O port pin descriptions.
2: RA6 and RA7 are only available as digital I/O in select oscillator modes. For more information, see Section 3.0 “Oscillator
Configurations”.
3: Unimplemented on the PIC18F65K22.
EUSART1
Comparator
MSSP1/2
3/5/7(3)
2/4/6/8/10(3)/12(3) CTMUTimer1 ADC
12-Bit
W
Instruction Bus <16>
STKPTR Bank
8
State Machine
Control Signals
Decode
8
8
EUSART2
ROM Latch
PORTC
PORTD
PORTE
PORTF
PORTG
RA0:RA7(1,2)
RC0:RC7(1)
RD0:RD7(1)
RE0: RE7(1)
RF1:RF7(1)
RG0:RG5(1)
PORTB
RB0:RB7(1)
OSC1/CLKI
OSC2/CLKO
VDD,
Timing
Generation
VSS MCLR
Power-up
Timer
Oscillator
Start-up Timer
Power-on
Reset
Watchdog
Timer
BOR and
LVD
Precision
Reference
Band Gap
INTRC
Oscillator
Regulator
Voltage
VDDCORE/VCAP
ENVREG
16 MHz
Oscillator
Timer0
4/5/6/7/8/9(3)/10(3) RTCC
Timer Timer
1/2/3
CCP ECCP
1/2/3
PIC18F87K22 FAMILY
DS39960C-page 14 2011 Microchip Technology Inc.
FIGURE 1-2: PIC18F8X K22 (80-PIN) BLOCK DIAGRAM
Instruction
Decode and
Control
Data Latch
Address Latch
Data Address<12>
12
Access
BSR FSR0
FSR1
FSR2
inc/dec
logic
Address
4124
PCH PCL
PCLATH
8
31-Level Stack
Program Counter
PRODLPRODH
8 x 8 Multiply
8
BITOP
8
8
ALU<8>
Address Latch
Program Memory
Data Latch
20
8
8
Table Pointer<21>
inc/dec logic
21
8
Data Bus<8>
Table Latch
8
IR
12
3
PCLATU
PCU
W
Instruction Bus <16>
STKPTR Bank
8
State Machine
Control Signals
Decode
8
8
ROM Latch
OSC1/CLKI
OSC2/CLKO
VDD,VSS MCLR
Power-up
Timer
Oscillator
Start-up Timer
Power-on
Reset
Watchdog
Timer
Precision
Reference
Band Gap
Regulator
Voltage
VDDCORE/VCAP
ENVREG
PORTA
PORTC
PORTD
PORTE
PORTF
PORTG
RA0:RA7(1,2)
RC0:RC7(1)
RD0:RD7(1)
RF1:RF7(1)
RG0:RG5(1)
PORTB
RB0:RB7(1)
PORTH
RH0:RH7(1)
PORTJ
RJ0:RJ7(1)
Note 1: See Table 1-3 for I/O port pin descriptions.
2: RA6 and RA7 are only available as digital I/O in select oscillator modes. See Section 3.0 “Oscillator Configurations” for
more information.
3: Unimplemented on the PIC18F85K22.
Timing
Generation
INTRC
Oscillator
16 MHz
Oscillator
RE0:RE7(1)
BOR and
LVD
Data Memory
(2/4 Kbytes)
EUSART1
Comparator
MSSP1/2
3/5/7(3)
2/4/6/8/10(3)/12(3) CTMUTimer1 ADC
12-Bit
EUSART2
Timer0
4/5/6/7/8/9(3)/10(3) RTCC
Timer Timer
1/2/3
CCP ECCP
1/2/3
System Bus Interface
AD15:0, A19:16
(Multiplexed with PORTD,
PORTE and PORTH)
2011 Microchip Technology Inc. DS39960C-page 15
PIC18F87K22 FAMILY
TABLE 1-3: PIC18F6XK22 PINOUT I/O DESCRIPTIONS
Pin Name Pin Number Pin
Type Buffer
Type Description
QFN/TQFP
MCLR/RG5
MCLR
RG5
7
I
I
ST
ST
Master Clear (input) or programming voltage (input).
This pin is an active-low Reset to the device.
General purpose, input only pin.
OSC1/CLKI/RA7
OSC1
CLKI
RA7
39
I
I
I/O
CMOS
CMOS
TTL
Oscillator crystal or external clock input.
Oscillator crystal input.
External clock source input. Always associated
with pin function, OSC1. (See related OSC1/CLKI,
OSC2/CLKO pins.)
General purpose I/O pin.
OSC2/CLKO/RA6
OSC2
CLKO
RA6
40
O
O
I/O
—
—
TTL
Oscillator crystal or clock output.
Oscillator crystal output. Connects to crystal or
resonator in Crystal Oscillator mode.
In certain oscillator modes, OSC2 pin outputs CLKO,
which has 1/4 the frequency of OSC1 and denotes the
instruction cycle rate.
General purpose I/O pin.
Legend: TTL = TTL compatible input CMOS = CMOS compatible input or output
ST = Schmitt Trigger input with CMOS levels Analog = Analog input
I = Input O = Output
P = Power OD = Open-Drain (no P diode to VDD)
I2C = I2C™/SMBus
Note 1: Default assignment for ECCP2 when the CCP2MX Configuration bit is set.
2: Alternate assignment for ECCP2 when the CCP2MX Configuration bit is cleared.
3: Not available on PIC18F65K22 and PIC18F85K22 devices.
4: The CC6, CCP7, CCP8 and CCP9 pin placement depends on the setting of the ECCPMX Configuration bit
(CONFIG3H<1>).
PIC18F87K22 FAMILY
DS39960C-page 16 2011 Microchip Technology Inc.
PORTA is a bidirectional I/O port.
RA0/AN0/ULPWU
RA0
AN0
ULPWU
24
I/O
I
I
TTL
Analog
Analog
Digital I/O.
Analog Input 0.
Ultra low-power wake-up input.
RA1/AN1
RA1
AN1
23
I/O
I
TTL
Analog
Digital I/O.
Analog Input 1.
RA2/AN2/VREF-
RA2
AN2
VREF-
22
I/O
I
I
TTL
Analog
Analog
Digital I/O.
Analog Input 2.
A/D reference voltage (low) input.
RA3/AN3/VREF+
RA3
AN3
VREF+
21
I/O
I
I
TTL
Analog
Analog
Digital I/O.
Analog Input 3.
A/D reference voltage (high) input.
RA4/T0CKI
RA4
T0CKI
28
I/O
I
ST
ST
Digital I/O.
Timer0 external clock input.
RA5/AN4/T1CKI/T3G/
HLVDIN
RA5
AN4
T1CKI
T3G
HLVDIN
27
I/O
I
I
I
I
TTL
Analog
ST
ST
Analog
Digital I/O.
Analog Input 4.
Timer1 clock input.
Timer3 external clock gate input.
High/Low-Voltage Detect input.
RA6 See the OSC2/CLKO/RA6 pin.
RA7 See the OSC1/CLKI/RA7 pin.
TABLE 1-3: PIC18F6XK22 PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Name Pin Number Pin
Type Buffer
Type Description
QFN/TQFP
Legend: TTL = TTL compatible input CMOS = CMOS compatible input or output
ST = Schmitt Trigger input with CMOS levels Analog = Analog input
I = Input O = Output
P = Power OD = Open-Drain (no P diode to VDD)
I2C = I2C™/SMBus
Note 1: Default assignment for ECCP2 when the CCP2MX Configuration bit is set.
2: Alternate assignment for ECCP2 when the CCP2MX Configuration bit is cleared.
3: Not available on PIC18F65K22 and PIC18F85K22 devices.
4: The CC6, CCP7, CCP8 and CCP9 pin placement depends on the setting of the ECCPMX Configuration bit
(CONFIG3H<1>).
2011 Microchip Technology Inc. DS39960C-page 17
PIC18F87K22 FAMILY
PORTB is a bidirectional I/O port. PORTB can be software
programmed for internal weak pull-ups on all inputs.
RB0/INT0/FLTO
RB0
INT0
FLT0
48
I/O
I
I
TTL
ST
ST
Digital I/O.
External Interrupt 0.
Enhanced PWM Fault input for ECCP1/2/3.
RB1/INT1
RB1
INT1
47
I/O
I
TTL
ST
Digital I/O.
External Interrupt 1.
RB2/INT2/CTED1
RB2
INT2
CTED1
46
I/O
I
I
TTL
ST
ST
Digital I/O.
External Interrupt 2.
CTMU Edge 1 input.
RB3/INT3/CTED2/
ECCP2/P2A
RB3
INT3
CTED2
ECCP2
P2A
45
I/O
I
I
I/O
O
TTL
ST
ST
ST
—
Digital I/O.
External Interrupt 3.
CTMU Edge 2 input.
Capture 2 input/Compare 2 output/PWM2.
Enhanced PWM2 Output A.
RB4/KBI0
RB4
KBI0
44
I/O
I
TTL
TTL
Digital I/O.
Interrupt-on-change pin.
RB5/KBI1/T3CKI/T1G
RB5
KBI1
T3CKI
T1G
43
I/O
I
I
I
TTL
TTL
ST
ST
Digital I/O.
Interrupt-on-change pin.
Timer3 clock input.
Timer1 external clock gate input.
RB6/KBI2/PGC
RB6
KBI2
PGC
42
I/O
I
I/O
TTL
TTL
ST
Digital I/O.
Interrupt-on-change pin.
In-Circuit Debugger and ICSP™ programming clock pin.
RB7/KBI3/PGD
RB7
KBI3
PGD
37
I/O
I
I/O
TTL
TTL
ST
Digital I/O.
Interrupt-on-change pin.
In-Circuit Debugger and ICSP programming data pin.
TABLE 1-3: PIC18F6XK22 PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Name Pin Number Pin
Type Buffer
Type Description
QFN/TQFP
Legend: TTL = TTL compatible input CMOS = CMOS compatible input or output
ST = Schmitt Trigger input with CMOS levels Analog = Analog input
I = Input O = Output
P = Power OD = Open-Drain (no P diode to VDD)
I2C = I2C™/SMBus
Note 1: Default assignment for ECCP2 when the CCP2MX Configuration bit is set.
2: Alternate assignment for ECCP2 when the CCP2MX Configuration bit is cleared.
3: Not available on PIC18F65K22 and PIC18F85K22 devices.
4: The CC6, CCP7, CCP8 and CCP9 pin placement depends on the setting of the ECCPMX Configuration bit
(CONFIG3H<1>).
PIC18F87K22 FAMILY
DS39960C-page 18 2011 Microchip Technology Inc.
PORTC is a bidirectional I/O port.
RC0/SOSCO/SCLKI
RC0
SOSCO
SCLKI
30
I/O
O
I
ST
—
ST
Digital I/O.
SOSC oscillator output.
Digital SOSC input.
RC1/SOSCI/ECCP2/P2A
RC1
SOSCI
ECCP2(1)
P2A
29
I/O
I
I/O
O
ST
CMOS
ST
—
Digital I/O.
SOSC oscillator input.
Capture 2 input/Compare2 output/PWM2 output.
Enhanced PWM2 Output A.
RC2/ECCP1/P1A
RC2
ECCP1
P1A
33
I/O
I/O
O
ST
ST
—
Digital I/O.
Capture 1 input/Compare 1 output/PWM1 output.
Enhanced PWM1 Output A.
RC3/SCK1/SCL1
RC3
SCK1
SCL1(4)
34
I/O
I/O
I/O
ST
ST
I2C
Digital I/O.
Synchronous serial clock input/output for SPI mode.
Synchronous serial clock input/output for I2C™ mode.
RC4/SDI1/SDA1
RC4
SDI1
SDA1(4)
35
I/O
I
I/O
ST
ST
I2C
Digital I/O.
SPI data in.
I2C data I/O.
RC5/SDO1
RC5
SDO1
36
I/O
O
ST
—
Digital I/O.
SPI data out.
RC6/TX1/CK1
RC6
TX1
CK1
31
I/O
O
I/O
ST
—
ST
Digital I/O.
EUSART asynchronous transmit.
EUSART synchronous clock (see related RX1/DT1).
RC7/RX1/DT1
RC7
RX1
DT1
32
I/O
I
I/O
ST
ST
ST
Digital I/O.
EUSART asynchronous receive.
EUSART synchronous data (see related TX1/CK1).
TABLE 1-3: PIC18F6XK22 PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Name Pin Number Pin
Type Buffer
Type Description
QFN/TQFP
Legend: TTL = TTL compatible input CMOS = CMOS compatible input or output
ST = Schmitt Trigger input with CMOS levels Analog = Analog input
I = Input O = Output
P = Power OD = Open-Drain (no P diode to VDD)
I2C = I2C™/SMBus
Note 1: Default assignment for ECCP2 when the CCP2MX Configuration bit is set.
2: Alternate assignment for ECCP2 when the CCP2MX Configuration bit is cleared.
3: Not available on PIC18F65K22 and PIC18F85K22 devices.
4: The CC6, CCP7, CCP8 and CCP9 pin placement depends on the setting of the ECCPMX Configuration bit
(CONFIG3H<1>).
2011 Microchip Technology Inc. DS39960C-page 19
PIC18F87K22 FAMILY
PORTD is a bidirectional I/O port.
RD0/PSP0/CTPLS
RD0
PSP0
CTPLS
58
I/O
I/O
O
ST
TTL
—
Digital I/O.
Parallel Slave Port data.
CTMU pulse generator output.
RD1/PSP1/T5CKI/T7G
RD1
PSP1
T5CKI
T7G
55
I/O
I/O
I
I
ST
TTL
ST
ST
Digital I/O.
Parallel Slave Port.
Timer5 clock input.
Timer7 external clock gate input.
RD2/PSP2
RD2
PSP2
54
I/O
O
ST
TTL
Digital I/O.
Parallel Slave Port.
RD3/PSP3
RD3
PSP3
53
I/O
I/O
ST
TTL
Digital I/O.
Parallel Slave Port.
RD4/PSP4/SDO2
RD4
PSP4
SDO2
52
I/O
I/O
O
ST
TTL
—
Digital I/O.
Parallel Slave Port.
SPI data out.
RD5/PSP5/SDI2/SDA2
RD5
PSP5
SDI2
SDA2
51
I/O
I/O
I
I/O
ST
TTL
ST
I2C
Digital I/O.
Parallel Slave Port.
SPI data in.
I2C™ data I/O.
RD6/PSP6/SCK2/SCL2
RD6
PSP6
SCK2
SCL2(4)
50
I/O
I/O
I/O
I/O
ST
TTL
ST
I2C
Digital I/O.
Parallel Slave Port.
Synchronous serial clock.
Synchronous serial clock I/O for I2C mode.
RD7/PSP7/SS2
RD7
PSP7
SS2
49
I/O
I/O
I
ST
TTL
TTL
Digital I/O.
Parallel Slave Port.
SPI slave select input.
TABLE 1-3: PIC18F6XK22 PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Name Pin Number Pin
Type Buffer
Type Description
QFN/TQFP
Legend: TTL = TTL compatible input CMOS = CMOS compatible input or output
ST = Schmitt Trigger input with CMOS levels Analog = Analog input
I = Input O = Output
P = Power OD = Open-Drain (no P diode to VDD)
I2C = I2C™/SMBus
Note 1: Default assignment for ECCP2 when the CCP2MX Configuration bit is set.
2: Alternate assignment for ECCP2 when the CCP2MX Configuration bit is cleared.
3: Not available on PIC18F65K22 and PIC18F85K22 devices.
4: The CC6, CCP7, CCP8 and CCP9 pin placement depends on the setting of the ECCPMX Configuration bit
(CONFIG3H<1>).
PIC18F87K22 FAMILY
DS39960C-page 20 2011 Microchip Technology Inc.
PORTE is a bidirectional I/O port.
RE0/RD/P2D
RE0
RD
P2D
2
I/O
I
O
ST
TTL
—
Digital I/O.
Parallel Slave Port read strobe.
EECP2 PWM Output D.
RE1/WR/P2C
RE1
WR
P2C
1
I/O
I
O
ST
TTL
—
Digital I/O.
Parallel Slave Port write strobe.
ECCP2 PWM Output C.
RE2/CS/P2B/CCP10
RE2
CS
P2B
CCP10(3)
64
I/O
I
O
I/O
ST
TTL
—
S/T
Digital I/O.
Parallel Slave Port chip select.
ECCP2 PWM Output B.
Capture 10 input/Compare 10 output/PWM10 output.
RE3/P3C/CCP9/REFO
RE3
P3C
CCP9(3,4)
REFO
63
I/O
O
I/O
O
ST
—
S/T
—
Digital I/O.
ECCP3 PWM Output C.
Capture 9 input/Compare 9 output/PWM9 output.
Reference clock out.
RE4/P3B/CCP8
RE4
P3B
CCP8(4)
62
I/O
O
I/O
ST
—
S/T
Digital I/O.
ECCP3 PWM Output B.
Capture 8 input/Compare 8 output/PWM8 output.
RE5/P1C/CCP7
RE5
P1C
CCP7(4)
61
I/O
O
I/O
ST
—
S/T
Digital I/O.
ECCP1 PWM Output C.
Capture 7 input/Compare 7 output/PWM7 output.
RE6/P1B/CCP6
RE6
P1B
CCP6(4)
60
I/O
O
I/O
ST
—
S/T
Digital I/O.
ECCP1 PWM Output B.
Capture 6 input/Compare 6 output/PWM6 output.
RE7/ECCP2/P2A
RE7
ECCP2(2)
P2A
59
I/O
I/O
O
ST
ST
—
Digital I/O.
Capture 2 input/Compare 2 output/PWM2 output.
ECCP2 PWM Output A.
TABLE 1-3: PIC18F6XK22 PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Name Pin Number Pin
Type Buffer
Type Description
QFN/TQFP
Legend: TTL = TTL compatible input CMOS = CMOS compatible input or output
ST = Schmitt Trigger input with CMOS levels Analog = Analog input
I = Input O = Output
P = Power OD = Open-Drain (no P diode to VDD)
I2C = I2C™/SMBus
Note 1: Default assignment for ECCP2 when the CCP2MX Configuration bit is set.
2: Alternate assignment for ECCP2 when the CCP2MX Configuration bit is cleared.
3: Not available on PIC18F65K22 and PIC18F85K22 devices.
4: The CC6, CCP7, CCP8 and CCP9 pin placement depends on the setting of the ECCPMX Configuration bit
(CONFIG3H<1>).
2011 Microchip Technology Inc. DS39960C-page 21
PIC18F87K22 FAMILY
PORTF is a bidirectional I/O port.
RF1/AN6/C2OUT/CTDIN
RF1
AN6
C2OUT
CTDIN
17
I/O
I
O
I
ST
Analog
—
ST
Digital I/O.
Analog Input 6.
Comparator 2 output.
CTMU pulse delay input.
RF2/AN7/C1OUT
RF2
AN7
C1OUT
16
I/O
I
O
ST
Analog
—
Digital I/O.
Analog Input 7.
Comparator 1 output.
RF3/AN8/C2INB/CTMUI
RF3
AN8
C2INB
CTMUI
15
I/O
I
I
O
ST
Analog
Analog
—
Digital I/O.
Analog Input 8.
Comparator 2 Input B.
CTMU pulse generator charger for the C2INB
comparator input.
RF4/AN9/C2INA
RF4
AN9
C2INA
14
I/O
I
I
ST
Analog
Analog
Digital I/O.
Analog Input 9.
Comparator 2 Input A.
RF5/AN10/CVREF/C1INB
RF5
AN10
CVREF
C1INB
13
I/O
I
O
I
ST
Analog
Analog
Analog
Digital I/O.
Analog Input 10.
Comparator reference voltage output.
Comparator 1 Input B.
RF6/AN11/C1INA
RF6
AN11
C1INA
12
I/O
I
I
ST
Analog
Analog
Digital I/O.
Analog Input 11.
Comparator 1 Input A.
RF7/AN5/SS1
RF7
AN5
SS1
11
I/O
O
I
ST
Analog
TTL
Digital I/O.
Analog Input 5.
SPI1 slave select input.
TABLE 1-3: PIC18F6XK22 PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Name Pin Number Pin
Type Buffer
Type Description
QFN/TQFP
Legend: TTL = TTL compatible input CMOS = CMOS compatible input or output
ST = Schmitt Trigger input with CMOS levels Analog = Analog input
I = Input O = Output
P = Power OD = Open-Drain (no P diode to VDD)
I2C = I2C™/SMBus
Note 1: Default assignment for ECCP2 when the CCP2MX Configuration bit is set.
2: Alternate assignment for ECCP2 when the CCP2MX Configuration bit is cleared.
3: Not available on PIC18F65K22 and PIC18F85K22 devices.
4: The CC6, CCP7, CCP8 and CCP9 pin placement depends on the setting of the ECCPMX Configuration bit
(CONFIG3H<1>).
PIC18F87K22 FAMILY
DS39960C-page 22 2011 Microchip Technology Inc.
PORTG is a bidirectional I/O port.
RG0/ECCP3/P3A
RG0
ECCP3
P3A
3
I/O
I/O
O
ST
ST
—
Digital I/O.
Capture 3 input/Compare 3 output/PWM3 output.
ECCP3 PWM Output A.
RG1/TX2/CK2/AN19/
C3OUT
RG1
TX2
CK2
AN19
C3OUT
4
I/O
O
I/O
I
O
ST
—
ST
Analog
—
Digital I/O.
EUSART asynchronous transmit.
EUSART synchronous clock (see related RX2/DT2).
Analog Input 19.
Comparator 3 output.
RG2/RX2/DT2/AN18/
C3INA
RG2
RX2
DT2
AN18
C3INA
5
I/O
I
I/O
I
I
ST
ST
ST
Analog
Analog
Digital I/O.
EUSART asynchronous receive.
EUSART synchronous data (see related TX2/CK2).
Analog Input 18.
Comparator 3 Input A.
RG3/CCP4/AN17/P3D/
C3INB
RG3
CCP4
AN17
P3D
C3INB
6
I/O
I/O
I
O
I
ST
S/T
Analog
—
Analog
Digital I/O.
Capture 4 input/Compare 4 output/PWM4 output.
Analog Input 18.
ECCP3 PWM Output D.
Comparator 3 Input B.
RG4/RTCC/T7CKI/T5G/
CCP5/AN16/P1D/C3INC
RG4
RTCC
T7CKI(3)
T5G
CCP5
AN16
P1D
C3INC
8
I/O
O
I
I
I/O
I
O
I
ST
—
ST
ST
ST
Analog
—
Analog
Digital I/O.
RTCC output
Timer7 clock input.
Timer5 external clock gate input.
Capture 5 input/Compare 5 output/PWM5 output.
Analog Input 16.
ECCP1 PWM Output D.
Comparator 3 Input C.
RG5 7 See the MCLR/RG5 pin.
TABLE 1-3: PIC18F6XK22 PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Name Pin Number Pin
Type Buffer
Type Description
QFN/TQFP
Legend: TTL = TTL compatible input CMOS = CMOS compatible input or output
ST = Schmitt Trigger input with CMOS levels Analog = Analog input
I = Input O = Output
P = Power OD = Open-Drain (no P diode to VDD)
I2C = I2C™/SMBus
Note 1: Default assignment for ECCP2 when the CCP2MX Configuration bit is set.
2: Alternate assignment for ECCP2 when the CCP2MX Configuration bit is cleared.
3: Not available on PIC18F65K22 and PIC18F85K22 devices.
4: The CC6, CCP7, CCP8 and CCP9 pin placement depends on the setting of the ECCPMX Configuration bit
(CONFIG3H<1>).
2011 Microchip Technology Inc. DS39960C-page 23
PIC18F87K22 FAMILY
VSS 9, 25, 41, 56 P — Ground reference for logic and I/O pins.
VDD 26, 38, 57 P — Positive supply for logic and I/O pins.
AVSS 20 P — Ground reference for analog modules.
AVDD 19 P — Positive supply for analog modules.
ENVREG 18 I ST Enable for on-chip voltage regulator.
VDDCORE/VCAP
VDDCORE
VCAP
10
P—
Core logic power or external filter capacitor connection.
External filter capacitor connection (regulator
enabled/disabled).
TABLE 1-3: PIC18F6XK22 PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Name Pin Number Pin
Type Buffer
Type Description
QFN/TQFP
Legend: TTL = TTL compatible input CMOS = CMOS compatible input or output
ST = Schmitt Trigger input with CMOS levels Analog = Analog input
I = Input O = Output
P = Power OD = Open-Drain (no P diode to VDD)
I2C = I2C™/SMBus
Note 1: Default assignment for ECCP2 when the CCP2MX Configuration bit is set.
2: Alternate assignment for ECCP2 when the CCP2MX Configuration bit is cleared.
3: Not available on PIC18F65K22 and PIC18F85K22 devices.
4: The CC6, CCP7, CCP8 and CCP9 pin placement depends on the setting of the ECCPMX Configuration bit
(CONFIG3H<1>).
PIC18F87K22 FAMILY
DS39960C-page 24 2011 Microchip Technology Inc.
TABLE 1- 4: PIC18F8XK22 PINOUT I/O DESCRIPTIONS
Pin Name Pin Number Pin
Type Buffer
Type Description
TQFP
MCLR/RG5
RG5
MCLR
9
I
I
ST
ST
Master Clear (input) or programming voltage (input).
This pin is an active-low Reset to the device.
General purpose, input only pin.
OSC1/CLKI/RA7
OSC1
CLKI
RA7
49
I
I
I/O
CMOS
CMOS
TTL
Oscillator crystal or external clock input.
Oscillator crystal input.
External clock source input. Always associated
with pin function, OSC1. (See related OSC1/CLKI,
OSC2/CLKO pins.)
General purpose I/O pin.
OSC2/CLKO/RA6
OSC2
CLKO
RA6
50
O
O
I/O
—
—
TTL
Oscillator crystal or clock output.
Oscillator crystal output. Connects to crystal or
resonator in Crystal Oscillator mode.
In certain oscillator modes, OSC2 pin outputs CLKO,
which has 1/4 the frequency of OSC1 and denotes the
instruction cycle rate.
General purpose I/O pin.
Legend: TTL = TTL compatible input CMOS = CMOS compatible input or output
ST = Schmitt Trigger input with CMOS levels Analog = Analog input
I = Input O = Output
P = Power OD = Open-Drain (no P diode to VDD)
I2C = I2C™/SMBus
Note 1: Default assignment for ECCP2 when the CCP2MX Configuration bit is set.
2: Alternate assignment for ECCP2 when the CCP2MX Configuration bit is cleared.
3: Not available on PIC18F65K22 and PIC18F85K22 devices.
4: PSP is available only in Microcontroller mode.
5: The CC6, CCP7, CCP8 and CCP9 pin placement depends on the setting of the ECCPMX Configuration bit
(CONFIG3H<1>).
2011 Microchip Technology Inc. DS39960C-page 25
PIC18F87K22 FAMILY
PORTA is a bidirectional I/O port.
RA0/AN0/ULPWU
RA0
AN0
ULPWU
30
I/O
I
I
TTL
Analog
Analog
Digital I/O.
Analog Input 0.
Ultra low-power wake-up input.
RA1/AN1
RA1
AN1
29
I/O
I
TTL
Analog
Digital I/O.
Analog Input 1.
RA2/AN2/VREF-
RA2
AN2
VREF-
28
I/O
I
I
TTL
Analog
Analog
Digital I/O.
Analog Input 2.
A/D reference voltage (low) input.
RA3/AN3/VREF+
RA3
AN3
VREF+
27
I/O
I
I
TTL
Analog
Analog
Digital I/O.
Analog Input 3.
A/D reference voltage (high) input.
RA4/T0CKI
RA4
T0CKI
34
I/O
I
ST
ST
Digital I/O.
Timer0 external clock input.
RA5/AN4/T1CKI/
T3G/HLVDIN
RA5
AN4
T1CKI
T3G
HLVDIN
33
I/O
I
I
I
I
TTL
Analog
ST
ST
Analog
Digital I/O.
Analog Input 4.
Timer1 clock input.
Timer3 external clock gate input.
High/Low-Voltage Detect input.
RA6 See the OSC2/CLKO/RA6 pin.
RA7 See the OSC1/CLKI/RA7 pin.
TABLE 1-4: PIC18F8XK22 PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Name Pin Number Pin
Type Buffer
Type Description
TQFP
Legend: TTL = TTL compatible input CMOS = CMOS compatible input or output
ST = Schmitt Trigger input with CMOS levels Analog = Analog input
I = Input O = Output
P = Power OD = Open-Drain (no P diode to VDD)
I2C = I2C™/SMBus
Note 1: Default assignment for ECCP2 when the CCP2MX Configuration bit is set.
2: Alternate assignment for ECCP2 when the CCP2MX Configuration bit is cleared.
3: Not available on PIC18F65K22 and PIC18F85K22 devices.
4: PSP is available only in Microcontroller mode.
5: The CC6, CCP7, CCP8 and CCP9 pin placement depends on the setting of the ECCPMX Configuration bit
(CONFIG3H<1>).
PIC18F87K22 FAMILY
DS39960C-page 26 2011 Microchip Technology Inc.
PORTB is a bidirectional I/O port. PORTB can be software
programmed for internal weak pull-ups on all inputs.
RB0/INT0/FLT0
RB0
INT0
FLT0
58
I/O
I
I
TTL
ST
ST
Digital I/O.
External Interrupt 0.
Enhanced PWM Fault input for ECCP1/2/3.
RB1/INT1
RB1
INT1
57
I/O
I
TTL
ST
Digital I/O.
External Interrupt 1.
RB2/INT2/CTED1
RB2
INT2
CTED1
56
I/O
I
I
TTL
ST
ST
Digital I/O.
External Interrupt 2.
CTMU Edge 1 input.
RB3/INT3/CTED2/
ECCP2/P2A
RB3
INT3
CTED2
ECCP2
P2A
55
I/O
I
I
I/O
O
TTL
ST
ST
ST
ST
Digital I/O.
External Interrupt 3.
CTMU Edge 2 input.
Capture 2 input/Compare 2 output/PWM2 output.
Enhanced PWM 2 Output A.
RB4/KBI0
RB4
KBI0
54
I/O
I
TTL
TTL
Digital I/O.
Interrupt-on-change pin.
RB5/KBI1/T3CKI/T1G
RB5
KBI1
T3CKI
T1G
53
I/O
I
I
I
TTL
TTL
ST
ST
Digital I/O.
Interrupt-on-change pin.
Timer3 clock input.
Timer1 external clock gate input.
RB6/KBI2/PGC
RB6
KBI2
PGC
52
I/O
I
I/O
TTL
TTL
ST
Digital I/O.
Interrupt-on-change pin.
In-Circuit Debugger and ICSP™ programming clock pin.
RB7/KBI3/PGD
RB7
KBI3
PGD
47
I/O
I
I/O
TTL
TTL
ST
Digital I/O.
Interrupt-on-change pin.
In-Circuit Debugger and ICSP programming data pin.
TABLE 1-4: PIC18F8XK22 PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Name Pin Number Pin
Type Buffer
Type Description
TQFP
Legend: TTL = TTL compatible input CMOS = CMOS compatible input or output
ST = Schmitt Trigger input with CMOS levels Analog = Analog input
I = Input O = Output
P = Power OD = Open-Drain (no P diode to VDD)
I2C = I2C™/SMBus
Note 1: Default assignment for ECCP2 when the CCP2MX Configuration bit is set.
2: Alternate assignment for ECCP2 when the CCP2MX Configuration bit is cleared.
3: Not available on PIC18F65K22 and PIC18F85K22 devices.
4: PSP is available only in Microcontroller mode.
5: The CC6, CCP7, CCP8 and CCP9 pin placement depends on the setting of the ECCPMX Configuration bit
(CONFIG3H<1>).
2011 Microchip Technology Inc. DS39960C-page 27
PIC18F87K22 FAMILY
PORTC is a bidirectional I/O port.
RC0/SOSCO/SCKLI
RC0
SOSCO
SCKLI
36
I/O
O
I
ST
—
ST
Digital I/O.
SOSC oscillator output.
Digital SOSC input.
RC1/SOSCI/ECCP2/P2A
RC1
SOSCI
ECCP2(1)
P2A
35
I/O
I
I/O
O
ST
CMOS
ST
—
Digital I/O.
SOSC oscillator input.
Capture 2 input/Compare 2 output/PWM2 output.
Enhanced PWM2 Output A.
RC2/ECCP1/P1A
RC2
ECCP1
P1A
43
I/O
I/O
O
ST
ST
—
Digital I/O.
Capture 1 input/Compare 1 output/PWM1 output.
Enhanced PWM1 Output A.
RC3/SCK1/SCL1
RC3
SCK1
SCL1
44
I/O
I/O
I/O
ST
ST
I2C
Digital I/O.
Synchronous serial clock input/output for SPI mode.
Synchronous serial clock input/output for I2C™ mode.
RC4/SDI1/SDA1
RC4
SDI1
SDA1
45
I/O
I
I/O
ST
ST
I2C
Digital I/O.
SPI data in.
I2C data I/O.
RC5/SDO1
RC5
SDO1
46
I/O
O
ST
—
Digital I/O.
SPI data out.
RC6/TX1/CK1
RC6
TX1
CK1
37
I/O
O
I/O
ST
—
ST
Digital I/O.
EUSART asynchronous transmit.
EUSART synchronous clock (see related RX1/DT1).
RC7/RX1/DT1
RC7
RX1
DT1
38
I/O
I
I/O
ST
ST
ST
Digital I/O.
EUSART asynchronous receive.
EUSART synchronous data (see related TX1/CK1).
TABLE 1-4: PIC18F8XK22 PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Name Pin Number Pin
Type Buffer
Type Description
TQFP
Legend: TTL = TTL compatible input CMOS = CMOS compatible input or output
ST = Schmitt Trigger input with CMOS levels Analog = Analog input
I = Input O = Output
P = Power OD = Open-Drain (no P diode to VDD)
I2C = I2C™/SMBus
Note 1: Default assignment for ECCP2 when the CCP2MX Configuration bit is set.
2: Alternate assignment for ECCP2 when the CCP2MX Configuration bit is cleared.
3: Not available on PIC18F65K22 and PIC18F85K22 devices.
4: PSP is available only in Microcontroller mode.
5: The CC6, CCP7, CCP8 and CCP9 pin placement depends on the setting of the ECCPMX Configuration bit
(CONFIG3H<1>).
PIC18F87K22 FAMILY
DS39960C-page 28 2011 Microchip Technology Inc.
PORTD is a bidirectional I/O port.
RD0/PSP0/CTPLS/AD0
RD0
PSP0(4)
CTPLS
AD0
72
I/O
I/O
O
I/O
ST
TTL
ST
TTL
Digital I/O
Parallel Slave Port data
CTMU pulse generator output
External Memory Address/Data 0
RD1/T5CKI/T7G/PSP1/AD1
RD1
T5CKI
T7G
PSP1
(4)
AD1
69
I/O
I
I
I/O
I/O
ST
ST
ST
TTL
TTL
Digital I/O
Timer5 clock input
Timer7 external clock gate input
Parallel Slave Port data
External Memory Address/Data 1
RD2/PSP2/AD2
RD2
PSP2(4)
AD2
68
I/O
I/O
I/O
ST
TTL
TTL
Digital I/O.
Parallel Slave Port data.
External Memory Address Data 2.
RD3/PSP3/AD3
RD3
PSP3(4)
AD3
67
I/O
I/O
I/O
ST
TTL
TTL
Digital I/O.
Parallel Slave Port data.
External Memory Address Data 3.
RD4/SDO2/PSP4/AD4
RD4
SDO2
PSP4(4)
AD4
66
I/O
O
I/O
I/O
ST
—
TTL
TTL
Digital I/O.
SPI data out.
Parallel Slave Port data.
External Memory Address Data 4.
RD5/SDI2/SDA2/PSP5/
AD5
RD5
SDI2
SDA2
PSP5(4)
AD5
65
I/O
I
I/O
I/O
I/O
ST
ST
I2C
TTL
TTL
Digital I/O.
SPI data in.
I2C™ data I/O.
Parallel Slave Port data.
External Memory Address Data 5.
TABLE 1-4: PIC18F8XK22 PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Name Pin Number Pin
Type Buffer
Type Description
TQFP
Legend: TTL = TTL compatible input CMOS = CMOS compatible input or output
ST = Schmitt Trigger input with CMOS levels Analog = Analog input
I = Input O = Output
P = Power OD = Open-Drain (no P diode to VDD)
I2C = I2C™/SMBus
Note 1: Default assignment for ECCP2 when the CCP2MX Configuration bit is set.
2: Alternate assignment for ECCP2 when the CCP2MX Configuration bit is cleared.
3: Not available on PIC18F65K22 and PIC18F85K22 devices.
4: PSP is available only in Microcontroller mode.
5: The CC6, CCP7, CCP8 and CCP9 pin placement depends on the setting of the ECCPMX Configuration bit
(CONFIG3H<1>).
2011 Microchip Technology Inc. DS39960C-page 29
PIC18F87K22 FAMILY
RD6/SCK2/SCL2/PSP6/
AD6
RD6
SCK2
SCL2
PSP6(4)
AD6
64
I/O
I/O
I/O
I/O
I/O
ST
ST
I2C
TTL
TTL
Digital I/O.
Synchronous serial clock input/output for SPI mode.
Synchronous serial clock input/output for I2C™ mode.
Parallel Slave Port data.
External Memory Address Data 6.
RD7/SS2/PSP7/AD7
RD7
SS2
PSP7(4)
AD7
63
I/O
I
I/O
I/O
ST
TTL
TTL
TTL
Digital I/O.
SPI slave select input.
Parallel Slave Port data.
External Memory Address Data 7.
TABLE 1-4: PIC18F8XK22 PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Name Pin Number Pin
Type Buffer
Type Description
TQFP
Legend: TTL = TTL compatible input CMOS = CMOS compatible input or output
ST = Schmitt Trigger input with CMOS levels Analog = Analog input
I = Input O = Output
P = Power OD = Open-Drain (no P diode to VDD)
I2C = I2C™/SMBus
Note 1: Default assignment for ECCP2 when the CCP2MX Configuration bit is set.
2: Alternate assignment for ECCP2 when the CCP2MX Configuration bit is cleared.
3: Not available on PIC18F65K22 and PIC18F85K22 devices.
4: PSP is available only in Microcontroller mode.
5: The CC6, CCP7, CCP8 and CCP9 pin placement depends on the setting of the ECCPMX Configuration bit
(CONFIG3H<1>).
PIC18F87K22 FAMILY
DS39960C-page 30 2011 Microchip Technology Inc.
PORTE is a bidirectional I/O port.
RE0/P2D/RD/AD8
RE0
P2D
RD(4)
AD8
4
I/O
O
I
I/O
ST
—
TTL
TTL
Digital I/O.
ECCP2 PWM Output D.
Parallel Slave Port read strobe.
External Memory Address/Data 8.
RE1/P2C/WR/AD9
RE1
P2C
WR(4)
AD9
3
I/O
O
I
I/O
ST
—
TTL
TTL
Digital I/O.
ECCP2 PWM Output C.
Parallel Slave Port write strobe.
External Memory Address/Data 9.
RE2/P2B/CCP10/CS/
AD10
RE2
P2B
CCP10(3)
CS(4)
AD10
78
I/O
O
I/O
I
I/O
ST
ST
ST
TTL
TTL
Digital I/O.
ECCP2 PWM Output B.
Capture 10 input/Compare 10 output/PWM10 output.
Parallel Slave Port chip select.
External Memory Address/Data 10.
RE3/P3C/CCP9/REFO
AD11
RE3
P3C
CCP9(3,5)
REFO
AD11
77
I/O
O
I/O
O
I/O
ST
—
S/T
—
TTL
Digital I/O.
ECCP3 PWM Output C.
Capture 9 input/Compare 9 output/PWM9 output.
Reference clock out.
External Memory Address/Data 11.
RE4/P3B/CCP8/AD12
RE4
P3B
CCP8(5)
AD12
76
I/O
O
I/O
I/O
ST
—
ST
TTL
Digital I/O.
ECCP4 PWM Output B.
Capture 8 input/Compare 8 output/PWM8 output.
External Memory Address/Data 12.
RE5/P1C/CCP7/AD13
RE5
P1C
CCP7(5)
AD13
75
I/O
O
I/O
I/O
ST
—
ST
TTL
Digital I/O.
ECCP1 PWM Output C.
Capture 7 input/Compare 7 output/PWM7 output.
External Memory Address/Data 13.
TABLE 1-4: PIC18F8XK22 PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Name Pin Number Pin
Type Buffer
Type Description
TQFP
Legend: TTL = TTL compatible input CMOS = CMOS compatible input or output
ST = Schmitt Trigger input with CMOS levels Analog = Analog input
I = Input O = Output
P = Power OD = Open-Drain (no P diode to VDD)
I2C = I2C™/SMBus
Note 1: Default assignment for ECCP2 when the CCP2MX Configuration bit is set.
2: Alternate assignment for ECCP2 when the CCP2MX Configuration bit is cleared.
3: Not available on PIC18F65K22 and PIC18F85K22 devices.
4: PSP is available only in Microcontroller mode.
5: The CC6, CCP7, CCP8 and CCP9 pin placement depends on the setting of the ECCPMX Configuration bit
(CONFIG3H<1>).
2011 Microchip Technology Inc. DS39960C-page 31
PIC18F87K22 FAMILY
RE6/P1B/CCP6/AD14
RE6
P1B
CCP6(5)
AD14
74
I/O
O
I/O
I/O
ST
—
ST
ST
Digital I/O.
ECCP1 PWM Output B.
Capture 6 input/Compare 6 output/PWM6 output.
External Memory Address/Data 14.
RE7/ECCP2/P2A/AD15
RE7
ECCP2(2)
P2A
AD15
73
I/O
I/O
O
I/O
ST
ST
—
ST
Digital I/O.
Capture 2 input/Compare 2 output/PWM2 output.
ECCP2 PWM Output A.
External Memory Address/Data 15.
TABLE 1-4: PIC18F8XK22 PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Name Pin Number Pin
Type Buffer
Type Description
TQFP
Legend: TTL = TTL compatible input CMOS = CMOS compatible input or output
ST = Schmitt Trigger input with CMOS levels Analog = Analog input
I = Input O = Output
P = Power OD = Open-Drain (no P diode to VDD)
I2C = I2C™/SMBus
Note 1: Default assignment for ECCP2 when the CCP2MX Configuration bit is set.
2: Alternate assignment for ECCP2 when the CCP2MX Configuration bit is cleared.
3: Not available on PIC18F65K22 and PIC18F85K22 devices.
4: PSP is available only in Microcontroller mode.
5: The CC6, CCP7, CCP8 and CCP9 pin placement depends on the setting of the ECCPMX Configuration bit
(CONFIG3H<1>).
PIC18F87K22 FAMILY
DS39960C-page 32 2011 Microchip Technology Inc.
PORTF is a bidirectional I/O port.
RF1/AN6/C2OUT/CTDIN
RF1
AN6
C2OUT
CTDIN
23
I/O
I
O
I
ST
Analog
—
ST
Digital I/O.
Analog Input 6.
Comparator 2 output.
CTMU pulse delay input.
RF2/AN7/C1OUT
RF2
AN7
C1OUT
18
I/O
I
O
ST
Analog
—
Digital I/O.
Analog Input 7.
Comparator 1 output.
RF3/AN8/C2INB/CTMUI
RF3
AN8
C2INB
CTMUI
17
I/O
I
I
O
ST
Analog
Analog
—
Digital I/O.
Analog Input 8.
Comparator 2 Input B.
CTMU pulse generator charger for the C2INB
comparator input.
RF4/AN9/C2INA
RF4
AN9
C2INA
16
I/O
I
I
ST
Analog
Analog
Digital I/O.
Analog Input 9.
Comparator 2 Input A.
RF5/AN10/C1INB
RF5
AN10
C1INB
15
I/O
I
I
ST
Analog
Analog
Digital I/O.
Analog Input 10.
Comparator 1 Input B.
RF6/AN11/C1INA
RF6
AN11
C1INA
14
I/O
I
I
ST
Analog
Analog
Digital I/O.
Analog Input 11.
Comparator 1 Input A.
RF7/AN5/SS1
RF7
AN5
SS1
13
I/O
O
I
ST
Analog
ST
Digital I/O.
Analog Input 5.
SPI slave select input.
TABLE 1-4: PIC18F8XK22 PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Name Pin Number Pin
Type Buffer
Type Description
TQFP
Legend: TTL = TTL compatible input CMOS = CMOS compatible input or output
ST = Schmitt Trigger input with CMOS levels Analog = Analog input
I = Input O = Output
P = Power OD = Open-Drain (no P diode to VDD)
I2C = I2C™/SMBus
Note 1: Default assignment for ECCP2 when the CCP2MX Configuration bit is set.
2: Alternate assignment for ECCP2 when the CCP2MX Configuration bit is cleared.
3: Not available on PIC18F65K22 and PIC18F85K22 devices.
4: PSP is available only in Microcontroller mode.
5: The CC6, CCP7, CCP8 and CCP9 pin placement depends on the setting of the ECCPMX Configuration bit
(CONFIG3H<1>).
2011 Microchip Technology Inc. DS39960C-page 33
PIC18F87K22 FAMILY
PORTG is a bidirectional I/O port.
RG0/ECCP3/P3A
RG0
ECCP3
P3A
5
I/O
I/O
O
ST
ST
—
Digital I/O.
Capture 3 input/Compare 3 output/PWM3 output.
ECCP3 PWM Output A.
RG1/TX2/CK2/AN19/
C3OUT
RG1
TX2
CK2
AN19
C3OUT
6
I/O
O
I/O
I
O
ST
—
ST
Analog
—
Digital I/O.
EUSART asynchronous transmit.
EUSART synchronous clock (see related RX2/DT2).
Analog Input 19.
Comparator 3 output.
RG2/RX2/DT2/AN18/
C3INA
RG2
RX2
DT2
AN18
C3INA
7
I/O
I
I/O
I
I
ST
ST
ST
Analog
Analog
Digital I/O.
EUSART asynchronous receive.
EUSART synchronous data (see related TX2/CK2).
Analog Input 18.
Comparator 3 Input A.
RG3/CCP4/AN17/P3D/
C3INB
RG3
CCP4
AN17
P3D
C3INB
8
I/O
I/O
I
O
I
ST
ST
Analog
—
Analog
Digital I/O.
Capture 4 input/Compare 4 output/PWM4 output.
Analog Input 17.
ECCP3 PWM Output D.
Comparator 3 Input B.
RG4/RTCC/T7CKI/T5G/
CCP5/AN16/P1D/C3INC
RG4
RTCC
T7CKI(3)
T5G
CCP5
AN16
P1D
C3INC
10
I/O
O
I
I
I/O
I
O
I
ST
—
ST
ST
ST
Analog
—
Analog
Digital I/O.
RTCC output.
Timer7 clock input.
Timer5 external clock gate input.
Capture 5 input/Compare 5 output/PWM5 output.
Analog Input 16.
ECCP1 PWM Output D.
Comparator 3 Input C.
RG5 9 See the MCLR/RG5 pin.
TABLE 1-4: PIC18F8XK22 PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Name Pin Number Pin
Type Buffer
Type Description
TQFP
Legend: TTL = TTL compatible input CMOS = CMOS compatible input or output
ST = Schmitt Trigger input with CMOS levels Analog = Analog input
I = Input O = Output
P = Power OD = Open-Drain (no P diode to VDD)
I2C = I2C™/SMBus
Note 1: Default assignment for ECCP2 when the CCP2MX Configuration bit is set.
2: Alternate assignment for ECCP2 when the CCP2MX Configuration bit is cleared.
3: Not available on PIC18F65K22 and PIC18F85K22 devices.
4: PSP is available only in Microcontroller mode.
5: The CC6, CCP7, CCP8 and CCP9 pin placement depends on the setting of the ECCPMX Configuration bit
(CONFIG3H<1>).
PIC18F87K22 FAMILY
DS39960C-page 34 2011 Microchip Technology Inc.
PORTH is a bidirectional I/O port.
RH0/AN23/A16
RH0
AN23
A16
79
I/O
I
I/O
ST
Analog
TTL
Digital I/O.
Analog Input 23.
External Memory Address/Data 16.
RH1/AN22/A17
RH1
AN22
A17
80
I/O
I
I/O
ST
Analog
TTL
Digital I/O.
Analog Input 22.
External Address/Data 17.
RH2/AN21/A18
RH2
AN21
A18
1
I/O
I
I/O
ST
Analog
TTL
Digital I/O.
Analog Input 21.
External Address/Data 18.
RH3/AN20/A19
RH3
AN20
A19
2
I/O
I
I/O
ST
Analog
TTL
Digital I/O.
Analog Input 20.
External Address/Data 19.
RH4/CCP9/P3C/AN12/
C2INC
RH4
CCP9(3,5)
P3C
AN12
C2INC
22
I/O
I/O
O
I
I
ST
ST
—
Analog
Analog
Digital I/O.
Capture 9 input/Compare 9 output/PWM9 output.
ECCP3 PWM Output C.
Analog Input 12.
Comparator 2 Input C.
RH5/CCP8/P3B/AN13/
C2IND
RH5
CCP8(5)
P3B
AN13
C2IND
21
I/O
I/O
O
I
I
ST
ST
—
Analog
Analog
Digital I/O.
Capture 8 input/Compare 8 output/PWM8 output.
ECCP3 PWM Output B.
Analog Input 13.
Comparator 1 Input D.
RH6/CCP7/P1C/AN14/
C1INC
RH6
CCP7(5)
P1C
AN14
C1INC
20
I/O
I/O
O
I
I
ST
ST
—
Analog
Analog
Digital I/O.
Capture 7 input/Compare 7 output/PWM7 output.
ECCP1 PWM Output C.
Analog Input 14.
Comparator 1 Input C.
TABLE 1-4: PIC18F8XK22 PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Name Pin Number Pin
Type Buffer
Type Description
TQFP
Legend: TTL = TTL compatible input CMOS = CMOS compatible input or output
ST = Schmitt Trigger input with CMOS levels Analog = Analog input
I = Input O = Output
P = Power OD = Open-Drain (no P diode to VDD)
I2C = I2C™/SMBus
Note 1: Default assignment for ECCP2 when the CCP2MX Configuration bit is set.
2: Alternate assignment for ECCP2 when the CCP2MX Configuration bit is cleared.
3: Not available on PIC18F65K22 and PIC18F85K22 devices.
4: PSP is available only in Microcontroller mode.
5: The CC6, CCP7, CCP8 and CCP9 pin placement depends on the setting of the ECCPMX Configuration bit
(CONFIG3H<1>).
2011 Microchip Technology Inc. DS39960C-page 35
PIC18F87K22 FAMILY
RH7/CCP6/P1B/AN15
RH7
CCP6(5)
P1B
AN15
19
I/O
I/O
O
I
ST
ST
—
Analog
Digital I/O.
Capture 6 input/Compare 6 output/PWM6 output.
ECCP1 PWM Output B.
Analog Input 15.
TABLE 1-4: PIC18F8XK22 PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Name Pin Number Pin
Type Buffer
Type Description
TQFP
Legend: TTL = TTL compatible input CMOS = CMOS compatible input or output
ST = Schmitt Trigger input with CMOS levels Analog = Analog input
I = Input O = Output
P = Power OD = Open-Drain (no P diode to VDD)
I2C = I2C™/SMBus
Note 1: Default assignment for ECCP2 when the CCP2MX Configuration bit is set.
2: Alternate assignment for ECCP2 when the CCP2MX Configuration bit is cleared.
3: Not available on PIC18F65K22 and PIC18F85K22 devices.
4: PSP is available only in Microcontroller mode.
5: The CC6, CCP7, CCP8 and CCP9 pin placement depends on the setting of the ECCPMX Configuration bit
(CONFIG3H<1>).
PIC18F87K22 FAMILY
DS39960C-page 36 2011 Microchip Technology Inc.
PORTJ is a bidirectional I/O port.
RJ0/ALE
RJ0
ALE
62
I/O
O
ST
—
Digital I/O.
External memory address latch enable.
RJ1/OE
RJ1
OE
61
I/O
O
ST
—
Digital I/O.
External memory output enable.
RJ2/WRL
RJ2
WRL
60
I/O
O
ST
—
Digital I/O.
External memory write low control.
RJ3/WRH
RJ3
WRH
59
I/O
O
ST
—
Digital I/O.
External memory high control.
RJ4/BA0
RJ4
BA0
39
I/O
O
ST
—
Digital I/O.
External Memory Byte Address 0 control
RJ5/CE
RJ5
CE
40
I/O
O
ST
—
Digital I/O
External memory chip enable control.
RJ6/LB
RJ6
LB
41
I/O
O
ST
—
Digital I/O.
External memory low byte control.
RJ7/UB
RJ7
UB
42
I/O
O
ST
—
Digital I/O.
External memory high byte control.
VSS 11, 31, 51, 70 P — Ground reference for logic and I/O pins.
VDD 32, 48, 71 P — Positive supply for logic and I/O pins.
AVSS 26 P — Ground reference for analog modules.
AVDD 25 P — Positive supply for analog modules.
ENVREG 24 I ST Enable for on-chip voltage regulator.
VDDCORE/VCAP
VDDCORE
VCAP
12
P—
Core logic power or external filter capacitor connection.
External filter capacitor connection (regulator
enabled/disabled).
TABLE 1-4: PIC18F8XK22 PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Name Pin Number Pin
Type Buffer
Type Description
TQFP
Legend: TTL = TTL compatible input CMOS = CMOS compatible input or output
ST = Schmitt Trigger input with CMOS levels Analog = Analog input
I = Input O = Output
P = Power OD = Open-Drain (no P diode to VDD)
I2C = I2C™/SMBus
Note 1: Default assignment for ECCP2 when the CCP2MX Configuration bit is set.
2: Alternate assignment for ECCP2 when the CCP2MX Configuration bit is cleared.
3: Not available on PIC18F65K22 and PIC18F85K22 devices.
4: PSP is available only in Microcontroller mode.
5: The CC6, CCP7, CCP8 and CCP9 pin placement depends on the setting of the ECCPMX Configuration bit
(CONFIG3H<1>).
2011 Microchip Technology Inc. DS39960C-page 37
PIC18F87K22 FAMILY
2.0 GUIDELINES FOR GETTING
STARTED WITH PIC18FXXKXX
MICROCONTROLLERS
2.1 Basic Connection Requirements
Getting started with the PIC18F87K22 family family of
8-bit microcontrollers requires attention to a minimal
set of device pin connections before proceeding with
development.
The following pins must always be connected:
•All V
DD and VSS pins
(see Section 2.2 “Power Supply Pins”)
•All AV
DD and AVSS pins, regardless of whether or
not the analog device features are used
(see Section 2.2 “Power Supply Pins”)
•MCLR
pin
(see Section 2.3 “Master Clear (MCLR) Pin”)
• ENVREG (if implemented) and VCAP/VDDCORE pins
(see Section 2.4 “Voltage Regulator Pins
(ENVREG and VCAP/VDDCORE)”)
These pins must also be connected if they are being
used in the end application:
• PGC/PGD pins used for In-Circuit Serial
Programming™ (ICSP™) and debugging purposes
(see Section 2.5 “ICSP Pins”)
• OSCI and OSCO pins when an external oscillator
source is used
(see Section 2.6 “External Oscillator Pins”)
Additionally, the following pins may be required:
•V
REF+/VREF- pins are used when external voltage
reference for analog modules is implemented
The minimum mandatory connections are shown in
Figure 2-1.
FIGURE 2-1: RECOMMENDED
MINIMUM CONNECTIONS
Note: The AVDD and AVSS pins must always be
connected, regardless of whether any of
the analog modules are being used.
PIC18FXXKXX
VDD
VSS
VDD
VSS
VSS
VDD
AVDD
AVSS
VDD
VSS
C1
R1
VDD
MCLR
VCAP/VDDCORE
R2 ENVREG
(1)
C7(2)
C2(2)
C3(2)
C4(2)
C5(2)
C6(2)
Key (all values are recommendations):
C1 through C6: 0.1 F, 20V ceramic
R1: 10 kΩ
R2: 100Ω to 470Ω
Note 1: See Section 2.4 “Voltage Regulator Pins
(ENVREG and VCAP/VDDCORE)” for
explanation of ENVREG pin connections.
2: The example shown is for a PIC18F device
with five VDD/VSS and AVDD/AVSS pairs.
Other devices may have more or less pairs;
adjust the number of decoupling capacitors
appropriately.
(1)
PIC18F87K22 FAMILY
DS39960C-page 38 2011 Microchip Technology Inc.
2.2 Power Supply Pins
2.2.1 DECOUPLING CAPACITORS
The use of decoupling capacitors on every pair of
power supply pins, such as VDD, VSS, AVDD and
AVSS, is required.
Consider the following criteria when using decoupling
capacitors:
•Value and type of capacitor: A 0.1 F (100 nF),
10-20V capacitor is recommended. The capacitor
should be a low-ESR device, with a resonance
frequency in the range of 200 MHz and higher.
Ceramic capacitors are recommended.
•Placement on the printed circuit board: The
decoupling capacitors should be placed as close
to the pins as possible. It is recommended to
place the capacitors on the same side of the
board as the device. If space is constricted, the
capacitor can be placed on another layer on the
PCB using a via; however, ensure that the trace
length from the pin to the capacitor is no greater
than 0.25 inch (6 mm).
•Handling high-frequency noise: If the board is
experiencing high-frequency noise (upward of
tens of MHz), add a second ceramic type capaci-
tor in parallel to the above described decoupling
capacitor. The value of the second capacitor can
be in the range of 0.01 F to 0.001 F. Place this
second capacitor next to each primary decoupling
capacitor. In high-speed circuit designs, consider
implementing a decade pair of capacitances as
close to the power and ground pins as possible
(e.g., 0.1 F in parallel with 0.001 F).
•Maximizing performance: On the board layout
from the power supply circuit, run the power and
return traces to the decoupling capacitors first,
and then to the device pins. This ensures that the
decoupling capacitors are first in the power chain.
Equally important is to keep the trace length
between the capacitor and the power pins to a
minimum, thereby reducing PCB trace
inductance.
2.2.2 TANK CAPACITORS
On boards with power traces running longer than
six inches in length, it is suggested to use a tank capac-
itor for integrated circuits, including microcontrollers, to
supply a local power source. The value of the tank
capacitor should be determined based on the trace
resistance that connects the power supply source to
the device, and the maximum current drawn by the
device in the application. In other words, select the tank
capacitor so that it meets the acceptable voltage sag at
the device. Typical values range from 4.7 F to 47 F.
2.3 Master Clear (MCLR) Pin
The MCLR pin provides two specific device
functions: Device Reset, and Device Programming
and Debugging. If programming and debugging are
not required in the end application, a direct
connection to VDD may be all that is required. The
addition of other components, to help increase the
application’s resistance to spurious Resets from
voltage sags, may be beneficial. A typical
configuration is shown in Figure 2-1. Other circuit
designs may be implemented, depending on the
application’s requirements.
During programming and debugging, the resistance
and capacitance that can be added to the pin must
be considered. Device programmers and debuggers
drive the MCLR pin. Consequently, specific voltage
levels (VIH and VIL) and fast signal transitions must
not be adversely affected. Therefore, specific values
of R1 and C1 will need to be adjusted based on the
application and PCB requirements. For example, it is
recommended that the capacitor, C1, be isolated
from the MCLR pin during programming and
debugging operations by using a jumper (Figure 2-2).
The jumper is replaced for normal run-time
operations.
Any components associated with the MCLR pin
should be placed within 0.25 inch (6 mm) of the pin.
FIGURE 2-2: EXAMPLE OF MCLR PIN
CONNECTIONS
Note 1: R1 10 k is recommended. A suggested
starting value is 10 k. Ensure that the
MCLR pin VIH and VIL specifications are met.
2: R2 470 will limit any current flowing into
MCLR from the external capacitor, C, in the
event of MCLR pin breakdown, due to
Electrostatic Discharge (ESD) or Electrical
Overstress (EOS). Ensure that the MCLR pin
VIH and VIL specifications are met.
C1
R2
R1
VDD
MCLR
PIC18FXXKXX
JP
2011 Microchip Technology Inc. DS39960C-page 39
PIC18F87K22 FAMILY
2.4 Volt a ge Regulator Pins (ENVREG
and VCAP/VDDCORE)
The on-chip voltage regulator enable pin, ENVREG,
must always be connected directly to either a supply
voltage or to ground. Tying ENVREG to VDD enables
the regulator, while tying it to ground disables the
regulator. Refer to Section 28.3 “On-Chip Voltage
Regulator” for details on connecting and using the
on-chip regulator.
When the regulator is enabled, a low-ESR (< 5Ω)
capacitor is required on the VCAP/VDDCORE pin to
stabilize the voltage regulator output voltage. The
VCAP/VDDCORE pin must not be connected to VDD and
must use a capacitor of 10 µF connected to ground. The
type can be ceramic or tantalum. Suitable examples of
capacitors are shown in Ta ble 2- 1. Capacitors with
equivalent specifications can be used.
Designers may use Figure 2-3 to evaluate ESR
equivalence of candidate devices.
It is recommended that the trace length not exceed
0.25 inch (6 mm). Refer to Section 31.0 “Electrical
Characteristics” for additional information.
When the regulator is disabled, the VCAP/VDDCORE pin
must be tied to a voltage supply at the VDDCORE level.
Refer to Section 31.0 “Electrical Characteristics” for
information on VDD and VDDCORE.
Some PIC18FXXKXX families, or some devices within
a family, do not provide the option of enabling or
disabling the on-chip voltage regulator:
• Some devices (with the name, PIC18LFXXKXX)
permanently disable the voltage regulator.
These devices do not have the ENVREG pin and
require a 0.1 F capacitor on the VCAP/VDDCORE
pin. The VDD level of these devices must comply
with the “voltage regulator disabled” specification
for Parameter D001, in Section 31.0 “Electrical
Characteristics”.
• Some devices permanently enable the voltage
regulator.
These devices also do not have the ENVREG pin.
The 10 F capacitor is still required on the
VCAP/VDDCORE pin.
FIGURE 2-3: FREQUENCY vs. ESR
PERFORMANCE FOR
SUGGESTED VCAP
.
10
1
0.1
0.01
0.001 0.01 0.1 1 10 100 1000 10,000
Frequ en cy (MH z)
ESR ()
Note: Typical data measurement at 25°C, 0V DC bias.
TABLE 2-1: SUITABLE CAPACITOR EQUIVALENTS
Make Part # Nominal
Capacitance Base Tolerance Rated Voltage Temp. Range
TDK C3216X7R1C106K 10 µF ±10% 16V -55 to 125ºC
TDK C3216X5R1C106K 10 µF ±10% 16V -55 to 85ºC
Panasonic ECJ-3YX1C106K 10 µF ±10% 16V -55 to 125ºC
Panasonic ECJ-4YB1C106K 10 µF ±10% 16V -55 to 85ºC
Murata GRM32DR71C106KA01L 10 µF ±10% 16V -55 to 125ºC
Murata GRM31CR61C106KC31L 10 µF ±10% 16V -55 to 85ºC
PIC18F87K22 FAMILY
DS39960C-page 40 2011 Microchip Technology Inc.
2.4.1 CONSIDERATIONS FOR CERAMIC
CAPACITORS
In recent years, large value, low-voltage, surface-mount
ceramic capacitors have become very cost effective in
sizes up to a few tens of microfarad. The low-ESR, small
physical size and other properties make ceramic
capacitors very attractive in many types of applications.
Ceramic capacitors are suitable for use with the inter-
nal voltage regulator of this microcontroller. However,
some care is needed in selecting the capacitor to
ensure that it maintains sufficient capacitance over the
intended operating range of the application.
Typical low-cost, 10 F ceramic capacitors are available
in X5R, X7R and Y5V dielectric ratings (other types are
also available, but are less common). The initial toler-
ance specifications for these types of capacitors are
often specified as ±10% to ±20% (X5R and X7R), or
-20%/+80% (Y5V). However, the effective capacitance
that these capacitors provide in an application circuit will
also vary based on additional factors, such as the
applied DC bias voltage and the temperature. The total
in-circuit tolerance is, therefore, much wider than the
initial tolerance specification.
The X5R and X7R capacitors typically exhibit satisfac-
tory temperature stability (ex: ±15% over a wide
temperature range, but consult the manufacturer’s data
sheets for exact specifications). However, Y5V capaci-
tors typically have extreme temperature tolerance
specifications of +22%/-82%. Due to the extreme
temperature tolerance, a 10 F nominal rated Y5V type
capacitor may not deliver enough total capacitance to
meet minimum internal voltage regulator stability and
transient response requirements. Therefore, Y5V
capacitors are not recommended for use with the
internal regulator if the application must operate over a
wide temperature range.
In addition to temperature tolerance, the effective
capacitance of large value ceramic capacitors can vary
substantially, based on the amount of DC voltage
applied to the capacitor. This effect can be very signifi-
cant, but is often overlooked or is not always
documented.
A typical DC bias voltage vs. capacitance graph for
X7R type and Y5V type capacitors is shown in
Figure 2-4.
FIGURE 2-4: DC BIAS VOLTAGE vs.
CAPACITANCE
CHARACTERISTICS
When selecting a ceramic capacitor to be used with the
internal voltage regulator, it is suggested to select a
high-voltage rating, so that the operating voltage is a
small percentage of the maximum rated capacitor volt-
age. For example, choose a ceramic capacitor rated at
16V for the 2.5V core voltage. Suggested capacitors
are shown in Table 2-1.
2.5 ICSP Pins
The PGC and PGD pins are used for In-Circuit Serial
Programming™ (ICSP™) and debugging purposes. It
is recommended to keep the trace length between the
ICSP connector and the ICSP pins on the device as
short as possible. If the ICSP connector is expected to
experience an ESD event, a series resistor is recom-
mended, with the value in the range of a few tens of
ohms, not to exceed 100Ω.
Pull-up resistors, series diodes and capacitors on the
PGC and PGD pins are not recommended as they will
interfere with the programmer/debugger communica-
tions to the device. If such discrete components are an
application requirement, they should be removed from
the circuit during programming and debugging. Alter-
natively, refer to the AC/DC characteristics and timing
requirements information in the respective device
Flash programming specification for information on
capacitive loading limits, and pin input voltage high
(VIH) and input low (VIL) requirements.
For device emulation, ensure that the “Communication
Channel Select” (i.e., PGCx/PGDx pins), programmed
into the device, matches the physical connections for
the ICSP to the Microchip debugger/emulator tool.
For more information on available Microchip
development tools connection requirements, refer to
Section 30.0 “Development Support”.
-80
-70
-60
-50
-40
-30
-20
-10
0
10
5 1011121314151617
DC Bias Voltage (VDC)
Capacitance Change (%)
01234 6789
16V Capacitor
10V Capacitor
6.3V Capacitor
2011 Microchip Technology Inc. DS39960C-page 41
PIC18F87K22 FAMILY
2.6 External Oscillator Pins
Many microcontrollers have options for at least two
oscillators: a high-frequency primary oscillator and a
low-frequency secondary oscillator (refer to
Section 3.0 “Oscillator Configurations” for details).
The oscillator circuit should be placed on the same
side of the board as the device. Place the oscillator
circuit close to the respective oscillator pins with no
more than 0.5 inch (12 mm) between the circuit
components and the pins. The load capacitors should
be placed next to the oscillator itself, on the same side
of the board.
Use a grounded copper pour around the oscillator cir-
cuit to isolate it from surrounding circuits. The
grounded copper pour should be routed directly to the
MCU ground. Do not run any signal traces or power
traces inside the ground pour. Also, if using a two-sided
board, avoid any traces on the other side of the board
where the crystal is placed.
Layout suggestions are shown in Figure 2-4. In-line
packages may be handled with a single-sided layout
that completely encompasses the oscillator pins. With
fine-pitch packages, it is not always possible to com-
pletely surround the pins and components. A suitable
solution is to tie the broken guard sections to a mirrored
ground layer. In all cases, the guard trace(s) must be
returned to ground.
In planning the application’s routing and I/O assign-
ments, ensure that adjacent port pins, and other
signals in close proximity to the oscillator, are benign
(i.e., free of high frequencies, short rise and fall times,
and other similar noise).
For additional information and design guidance on
oscillator circuits, please refer to these Microchip
Application Notes, available at the corporate web site
(www.microchip.com):
•AN826, “Crystal Oscillator Ba sics and Crystal
Selection for rfPIC™ and PICmicro® Devices”
• AN849, “Basic PICmicro® Oscillator Design”
• AN943, “Practical PICmicro® Oscillator Analysis
and Design”
•AN949, “Ma king Your Oscillator Work ”
2.7 Unused I/Os
Unused I/O pins should be configured as outputs and
driven to a logic low state. Alternatively, connect a 1 kΩ
to 10 kΩ resistor to VSS on unused pins and drive the
output to logic low.
FIGURE 2-5: SUGGESTED
PLACEMENT OF THE
OSCILLATOR CIRCUIT
GND
`
`
`
OSC1
OSC2
T1OSO
T1OS I
Copper Pour Primary Oscillator
Crystal
Timer1 Oscillator
Crystal
DEVICE PINS
Primary
Oscillator
C1
C2
T1 Oscillator: C1 T1 Oscillator: C2
(tied to ground)
Single-Sided and In-Line Layouts:
Fine-Pitch (Dual-Sided) Layouts:
GND
OSCO
OSCI
Bottom Layer
Copper Pour
Oscillator
Crystal
Top Layer Copper Pour
C2
C1
DEVICE PINS
(tied to ground)
(tied to ground)
PIC18F87K22 FAMILY
DS39960C-page 42 2011 Microchip Technology Inc.
NOTES:
2011 Microchip Technology Inc. DS39960C-page 43
PIC18F87K22 FAMILY
3.0 OSCILLATOR
CONFIGURATIONS
3.1 Oscillator Types
The PIC18F87K22 family of devices can be operated in
the following oscillator modes:
• EC External clock, RA6 available
• ECIO External clock, clock out RA6 (FOSC/4 on
RA6)
• HS High-Speed Crystal/Resonator
• XT Crystal/Resonator
• LP Low-Power Crystal
• RC External Resistor/Capacitor, RA6
available
• RCIO External Resistor/Capacitor, clock out
RA6 (FOSC/4 on RA6)
• INTIO2 Internal Oscillator with I/O on RA6 and
RA7
• INTIO1 Internal Oscillator with FOSC/4 output on
RA6 and I/O on RA7
There is also an option for running the 4xPLL on any of
the clock sources in the input frequency range of 4 to
16 MHz.
The PLL is enabled by setting the PLLCFG bit
(CONFIG1H<4>) or the PLLEN bit (OSCTUNE<6>).
For the EC and HS mode, the PLLEN (software) or
PLLCFG (CONFIG) bit can be used to enable the PLL.
For the INTIOx modes (HF-INTOSC):
• Only the PLLEN can enable the PLL (PLLCFG is
ignored).
• When the oscillator is configured for the internal
oscillator (FOSC<3:0> = 100x), the PLL can be
enabled only when the HF-INTOSC frequency is
8 or 16 MHz.
When the RA6 and RA7 pins are not used for an oscil-
lator function or CLKOUT function, they are available
as general purpose I/Os.
To optimize power consumption when using EC/HS/
XT/LP/RC as the primary oscillator, the frequency input
range can be configured to yield an optimized power
bias:
• Low-Power Bias – External frequency less than
160 kHz
• Medium Power Bias – External frequency
between 160 kHz and 16 MHz
• High-Power Bias – External frequency greater
than 16 MHz
All of these modes are selected by the user by
programming the FOSC<3:0> Configuration bits
(CONFIG1H<3:0>). In addition, PIC18F87K22 family
devices can switch between different clock sources,
either under software control or, under certain condi-
tions, automatically. This allows for additional power
savings by managing device clock speed in real time
without resetting the application. The clock sources for
the PIC18F87K22 family of devices are shown in
Figure 3-1.
For the HS and EC mode, there are additional power
modes of operation – depending on the frequency of
operation.
HS1 is the Medium power mode with a frequency range
of 4 MHz to 16 MHz. HS2 is the High-Power mode,
where the oscillator frequency can go from 16 MHz to
25 MHz. HS1 and HS2 are achieved by setting the
CONFIG1H<3:0> correctly. (For details, see
Register 28-2 on page 406.)
EC mode has these modes of operation:
• EC1 – For low power with a frequency range up to
160 kHz
• EC2 – Medium power with a frequency range of
160 kHz to 16 MHz
• EC3 – High power with a frequency range of
16 MHz to 64 MHz
EC1, EC2 and EC3 are achieved by setting the
CONFIG1H<3:0> correctly. (For details, see
Register 28-2 on page 406.)
Table 3-1 shows the HS and EC modes’ frequency
range and FOSC<3:0> settings.
PIC18F87K22 FAMILY
DS39960C-page 44 2011 Microchip Technology Inc.
FIGURE 3-1: PIC18F87 K22 FAMILY CLOCK DIAGRAM
TABLE 3-1: HS, EC, XT, LP AND RC MODES: RANGES AND SETTINGS
Mode Frequency Range FOSC<3:0> Setting
EC1 (low power) DC-160 kHz 1101
(EC1 & EC1IO) 1100
EC2 (medium power) 160kHz-16MHz 1011
(EC2 & EC2IO) 1010
EC3 (high power) 16 MHz-64 MHz 0101
(EC3 & EC3IO) 0100
HS1 (medium power) 4 MHz-16 MHz 0011
HS2 (high power) 16 MHz-25 MHz 0010
XT 100 kHz-4 MHz 0001
LP 31.25 kHz 0000
RC (External) 0-4 MHz 001x
INTIO 32 KHz-16 MHz 100x
(and OSCCON, OSCCON2)
OSC2
OSC1
SOSCO
SOSCI
HF INTOSC
16 MHz to
31 kHz
MF INTOSC
500 kHz to
31 kHz
LF INTOSC
31 kHz
Postscaler
Postscaler
16 MHz
8 MHz
4 MHz
2 MHz
1 MHz
500 kHz
250 kHz
31 kHz
500 kHz
250 kHz
31 kHz
31 kHz
16 MHz
8 MHz
4 MHz
2 MHz
1 MHz
500 kHz
250 kHz
31 kHz
4x PLL
FOSC<3:0>
INTSRC
MUX
MUX
MUX
MUX
MFIOSEL
Mux
Peripherals
CPU
IDLEN
Clock Control
FOSC<3:0>
SCS<1:0>
111
110
101
100
011
010
001
000
IRCF<2:0>
MUX
PLLEN
and PLLCFG
2011 Microchip Technology Inc. DS39960C-page 45
PIC18F87K22 FAMILY
3.2 Control Registers
The OSCCON register (Register 3-1) controls the main
aspects of the device clock’s operation. It selects the
oscillator type to be used, which of the power-managed
modes to invoke and the output frequency of the
INTOSC source. It also provides status on the oscillators.
The OSCTUNE register (Register 3-3) controls the
tuning and operation of the internal oscillator block. It also
implements the PLLEN bit which controls the operation of
the Phase Locked Loop (PLL) (see
Section 3.5.3 “PLL
Frequency Multiplier”
).
REGISTER 3-1: OSCCON: OSCILLATOR CONTROL REGISTER(1)
R/W-0 R/W-1 R/W-1 R/W-0 R(1) R-0 R/W-0 R/W-0
IDLEN IRCF2(2) IRCF1(2) IRCF0(2) OSTS HFIOFS SCS1(4) SCS0(4)
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 IDLEN: Idle Enable bit
1 = Device enters an Idle mode when a SLEEP instruction is executed
0 = Device enters Sleep mode when a SLEEP instruction is executed
bit 6-4 IRCF<2:0>: Internal Oscillator Frequency Select bits(2)
111 = HF-INTOSC output frequency used (16 MHz)
110 = HF-INTOSC/2 output frequency used (8 MHz, default)
101 = HF-INTOSC/4 output frequency used (4 MHz)
100 = HF-INTOSC/8 output frequency used (2 MHz)
011 = HF-INTOSC/16 output frequency used (1 MHz)
If INTSRC = 0 and MFIOSEL = 0:(3,5)
010 = HF-INTOSC/32 output frequency used (500 kHz)
001 = HF-INTOSC/64 output frequency used (250 kHz)
000 = LF-INTOSC output frequency used (31.25 kHz)
If INTSRC = 1 and MFIOSEL = 0:(3,5)
010 = HF-INTOSC/32 output frequency used (500 kHz)
001 = HF-INTOSC/64 output frequency used (250 kHz)
000 = HF-INTOSC/512 output frequency used (31.25 kHz)
If INTSRC = 0 and MFIOSEL = 1:(3,5)
010 = MF-INTOSC output frequency used (500 kHz)
001 = MF-INTOSC/2 output frequency used (250 kHz)
000 = LF-INTOSC output frequency used (31.25 kHz)(6)
If INTSRC = 1 and MFIOSEL = 1:(3,5)
010 = MF-INTOSC output frequency used (500 kHz)
001 = MF-INTOSC/2 output frequency used (250 kHz)
000 = MF-INTOSC/16 output frequency used (31.25 kHz)
bit 3 OSTS: Oscillator Start-up Timer Time-out Status bit(1)
1 = Oscillator Start-up Timer (OST) time-out has expired; primary oscillator is running, as defined by
FOSC<3:0>
0 = Oscillator Start-up Timer (OST) time-out is running; primary oscillator is not ready – device is
running from internal oscillator (HF-INTOSC, MF-INTOSC or LF-INTOSC)
Note 1: The Reset state depends on the state of the IESO Configuration bit (CONFIG1H<7>).
2: Modifying these bits will cause an immediate clock frequency switch if the internal oscillator is providing
the device clocks.
3: Source selected by the INTSRC bit (OSCTUNE<7>).
4: Modifying these bits will cause an immediate clock source switch.
5: INTSRC = OSCTUNE<7> and MFIOSEL = OSCCON2<0>.
6: Lowest power option for an internal source.
PIC18F87K22 FAMILY
DS39960C-page 46 2011 Microchip Technology Inc.
bit 2 HFIOFS: INTOSC Frequency Stable bit
1 = HF-INTOSC oscillator frequency is stable
0 = HF-INTOSC oscillator frequency is not stable
bit 1-0 SCS<1:0>: System Clock Select bits(4)
1x = Internal oscillator block (LF-INTOSC, MF-INTOSC or HF-INTOSC)
01 = SOSC oscillator
00 = Default primary oscillator (OSC1/OSC2 or HF-INTOSC with or without PLL. Defined by the
FOSC<3:0> Configuration bits, CONFIG1H<3:0>.)
REGISTER 3-1: OSCCON: OSCILLATOR CONTROL REGISTER(1) (CONTINUED)
Note 1: The Reset state depends on the state of the IESO Configuration bit (CONFIG1H<7>).
2: Modifying these bits will cause an immediate clock frequency switch if the internal oscillator is providing
the device clocks.
3: Source selected by the INTSRC bit (OSCTUNE<7>).
4: Modifying these bits will cause an immediate clock source switch.
5: INTSRC = OSCTUNE<7> and MFIOSEL = OSCCON2<0>.
6: Lowest power option for an internal source.
REGISTER 3-2: OSCCON2: OSCILLATOR CONTROL REGISTER 2
U-0 R-0 U-0 U-0 R/W-0 U-0 R-x R/W-0
— SOSCRUN ——SOSCGO— MFIOFS MFIOSEL
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 Unimplemented: Read as ‘0’
bit 6 SOSCRUN: SOSC Run Status bit
1 = System clock comes from a secondary SOSC
0 = System clock comes from an oscillator other than SOSC
bit 5-4 Unimplemented: Read as ‘0’
bit 3 SOSCGO: Oscillator Start Control bit
1 = Oscillator is running, even if no other sources are requesting it
0 = Oscillator is shut off if no other sources are requesting it (When the SOSC is selected to run from
a digital clock input, rather than an external crystal, this bit has no effect.)
bit 2 Unimplemented: Read as ‘0’
bit 1 MFIOFS: MF-INTOSC Frequency Stable bit
1 = MF-INTOSC is stable
0 = MF-INTOSC is not stable
bit 0 MFIOSEL: MF-INTOSC Select bit
1 = MF-INTOSC is used in place of HF-INTOSC frequencies of 500 kHz, 250 kHz and 31.25 kHz
0 = MF-INTOSC is not used
2011 Microchip Technology Inc. DS39960C-page 47
PIC18F87K22 FAMILY
REGISTER 3-3: OSCTUNE: OSCILLATOR TUNING REGISTER
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0
INTSRC PLLEN TUN5 TUN4 TUN3 TUN2 TUN1 TUN0
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 INTSRC: Internal Oscillator Low-Frequency Source Select bit
1 = 31.25 kHz device clock derived from 16 MHz INTOSC source (divide-by-512 enabled, HF-INTOSC)
0 = 31 kHz device clock derived from INTRC 31 kHz oscillator (LF-INTOSC)
bit 6 PLLEN: Frequency Multiplier PLL Enable bit
1 = PLL is enabled
0 = PLL is disabled
bit 5-0 TUN<5:0>: Fast RC Oscillator (INTOSC) Frequency Tuning bits
011111 = Maximum frequency
• •
• •
000001
000000 = Center frequency; fast RC oscillator is running at the calibrated frequency
111111
• •
• •
100000 = Minimum frequency
PIC18F87K22 FAMILY
DS39960C-page 48 2011 Microchip Technology Inc.
3.3 Clock Sources and
Oscillator Switching
Essentially, PIC18F87K22 family devices have these
independent clock sources:
• Primary oscillators
• Secondary oscillators
• Internal oscillator
The primary oscillators can be thought of as the main
device oscillators. These are any external oscillators
connected to the OSC1 and OSC2 pins, and include
the External Crystal and Resonator modes and the
External Clock modes. If selected by the FOSC<3:0>
Configuration bits (CONFIG1H<3:0>), the internal
oscillator block may be considered a primary oscillator.
The internal oscillator block can be one of the following:
• 31 kHz LF-INTRC source
• 31 kHz to 500 kHz MF-INTOSC source
• 31 kHz to 16 MHz HF-INTOSC source
The particular mode is defined by the FOSC
Configuration bits. The details of these modes are
covered in Section 3.5 “External Oscillator Modes”.
The secondary oscillators are external clock
sources that are not connected to the OSC1 or OSC2
pin. These sources may continue to operate, even
after the controller is placed in a power-managed
mode. PIC18F87K22 family devices offer the SOSC
(Timer1/3/5/7) oscillator as a secondary oscillator
source. This oscillator, in all power-managed modes, is
often the time base for functions, such as a Real-Time
Clock (RTC).
The SOSC can be enabled from any peripheral that
requests it. There are eight ways the SOSC can be
enabled: if the SOSC is selected as the source by any
of the odd timers, which is done by each respective
SOSCEN bit (TxCON<3>), if the SOSC is selected as
the RTCC source by the RTCOSC Configuration bit
(CONFIG3L<1>), if the SOSC is selected as the CPU
clock source by the SCS bits (OSCCON<1:0>) or if the
SOSCGO bit is set (OSCCON2<3>). The SOSCGO bit
is used to warm up the SOSC so that it is ready before
any peripheral requests it.
The secondary oscillator has three Run modes. The
SOSCSEL<1:0> bits (CONFIG1L<4:3>) decide the
SOSC mode of operation:
•11 = High-power SOSC circuit
•10 = Digital (SCLKI) mode
•01 = Low-power SOSC circuit
If a secondary oscillator is not desired and digital I/O on
port pins, RC0 and RC1, is needed, the SOSCSEL bits
must be set to Digital mode.
In addition to being a primary clock source in some
circumstances, the internal os cillator is available as a
power-managed mode clock source. The LF-INTOSC
source is also used as the clock source for several
special features, such as the WDT and Fail-Safe Clock
Monitor. The internal oscillator block is discussed in
more detail in Section 3.6 “Internal Oscillator
Block”.
The PIC18F87K22 family includes features that allow
the device clock source to be switched from the main
oscillator, chosen by device configuration, to one of the
alternate clock sources. When an alternate clock
source is enabled, various power-managed operating
modes are available.
3.3.1 OSC1/OSC2 OSCILLATOR
The OSC1/OSC2 oscillator block is used to provide the
oscillator modes and frequency ranges:
The crystal-based oscillators (XT, HS and LP) have a
built-in start-up time. The operation of the EC and
EXTRC clocks is immediate.
3.3.2 CLOCK SOURCE SELECTION
The System Clock Select bits, SCS<1:0>
(OSCCON2<1:0>), select the clock source. The avail-
able clock sources are the primary clock defined by the
FOSC<3:0> Configuration bits, the secondary clock
(SOSC oscillator) and the internal oscillator. The clock
source changes after one or more of the bits is written
to, following a brief clock transition interval.
The OSTS (OSCCON<3>) and SOSCRUN
(OSCCON<6>) bits indicate which clock source is
currently providing the device clock. The OSTS bit
indicates that the Oscillator Start-up Timer (OST) has
timed out and the primary clock is providing the device
clock in primary clock modes. The SOSCRUN bit indi-
cates when the SOSC oscillator (from Timer1/3/5/7) is
providing the device clock in secondary clock modes.
In power-managed modes, only one of these bits will
be set at any time. If neither of these bits is set, the
INTRC is providing the clock, or the internal oscillator
has just started and is not yet stable.
The IDLEN bit (OSCCON<7>) determines if the device
goes into Sleep mode or one of the Idle modes when
the SLEEP instruction is executed.
Mode Design Operating Frequency
LP 31.25-100 kHz
XT 100 kHz to 4 MHz
HS 4 MHz to 25 MHz
EC 0 to 64 MHz (external clock)
EXTRC 0 to 4 MHz (external RC)
2011 Microchip Technology Inc. DS39960C-page 49
PIC18F87K22 FAMILY
The use of the flag and control bits in the OSCCON
register is discussed in more detail in Section 4.0
“Power-M ana ged Modes”.
3.3.2.1 System Clock Selection and Device
Resets
Since the SCS bits are cleared on all forms of Reset,
this means the primary oscillator, defined by the
FOSC<3:0> Configuration bits, is used as the primary
clock source on device Resets. This could either be the
internal oscillator block by itself, or one of the other
primary clock source (HS, EC, XT, LP, External RC and
PLL-enabled modes).
In those cases when the internal oscillator block, with-
out PLL, is the default clock on Reset, the Fast RC
oscillator (INTOSC) will be used as the device clock
source. It will initially start at 8 MHz; the postscaler
selection that corresponds to the Reset value of the
IRCF<2:0> bits (‘110’).
Regardless of which primary oscillator is selected,
INTRC will always be enabled on device power-up. It
serves as the clock source until the device has loaded
its configuration values from memory. It is at this point
that the FOSC Configuration bits are read and the
oscillator selection of the operational mode is made.
Note that either the primary clock source or the internal
oscillator will have two bit setting options for the possible
values of the SCS<1:0> bits, at any given time.
3.3.3 OSCILLATOR TRANSITIONS
PIC18F87K22 family devices contain circuitry to
prevent clock “glitches” when switching between clock
sources. A short pause in the device clock occurs
during the clock switch. The length of this pause is the
sum of two cycles of the old clock source and three to
four cycles of the new clock source. This formula
assumes that the new clock source is stable.
Clock transitions are discussed in greater detail in
Section 4.1.2 “Entering Power-Managed Modes”.
3.4 RC Oscillator
For timing-insensitive applications, the RC and RCIO
Oscillator modes offer additional cost savings. The
actual oscillator frequency is a function of several
factors:
• Supply voltage
• Values of the external resistor (REXT) and capacitor
(CEXT)
• Operating temperature
Given the same device, operating voltage and temper-
ature, and component values, there will also be unit to
unit frequency variations. These are due to factors,
such as:
• Normal manufacturing variation
• Difference in lead frame capacitance between
package types (especially for low CEXT values)
• Variations within the tolerance of limits of REXT
and CEXT
In the RC Oscillator mode, the oscillator frequency,
divided by 4, is available on the OSC2 pin. This signal
may be used for test purposes or to synchronize other
logic. Figure 3-2 shows how the R/C combination is
connected.
FIGURE 3-2: RC OSCILLATOR MODE
The RCIO Oscillator mode (Figure 3-3) functions like
the RC mode, except that the OSC2 pin becomes an
additional general purpose I/O pin. The I/O pin
becomes bit 6 of PORTA (RA6).
FIGURE 3-3: RCIO OSCILLATOR MODE
Note 1: The Timer1/3/5/7 oscillator must be
enabled to select the secondary clock
source. The Timerx oscillator is enabled by
setting the SOSCEN bit in the Timerx Con-
trol register (TxCON<3>). If the Timerx
oscillator is not enabled, then any attempt
to select a secondary clock source when
executing a SLEEP instruction will be
ignored.
2: It is recommended that the Timerx
oscillator be operating and stable before
executing the SLEEP instruction or a very
long delay may occur while the Timerx
oscillator starts.
OSC2/CLKO
CEXT
REXT
PIC18FXXXX
OSC1
FOSC/4
Internal
Clock
VDD
VSS
Recommended values: 3 k REXT 100 k
20 pF CEXT 300 pF
CEXT
REXT
PIC18FXXXX
OSC1 Internal
Clock
VDD
VSS
Recommended values: 3 k REXT 100 k
20 pF CEXT 300 pF
I/O (OSC2)
RA6
PIC18F87K22 FAMILY
DS39960C-page 50 2011 Microchip Technology Inc.
3.5 External Oscillator Modes
3.5.1 CRYSTAL OSCILLATOR/CERAMIC
RESONATORS (HS MODES)
In HS or HSPLL Oscillator modes, a crystal or ceramic
resonator is connected to the OSC1 and OSC2 pins to
establish oscillation. Figure 3-4 shows the pin
connections.
The oscillator design requires the use of a crystal rated
for parallel resonant operation.
TABLE 3-2: CAPACITOR SELECTION FOR
CERAMIC RESO NATORS
T ABLE 3-3: CAPACITOR SELECTION FOR
CRYSTAL OSCILLATOR
FIGURE 3-4: CRYSTAL/CERAMIC
RESONATOR OPERATION
(HS OR HSPLL
CONFIGURATION)
Note: Use of a crystal rated for series resonant
operation may give a frequency out of the
crystal manufacturer’s specifications.
Typical Capacitor Values Used:
Mode Freq. OSC1 OSC2
HS 8.0 MHz
16.0 MHz
27 pF
22 pF
27 pF
22 pF
Capacitor values are for design guidance only.
Different capacitor values may be required to produce
acceptable oscillator operation. The user should test
the performance of the oscillator over the expected
VDD and temperature range for the application. Refer
to the following application notes for oscillator-specific
information:
• AN588, “PIC® Microc ontroller Oscillator Design
Guide”
• AN826, “Crystal Oscillator Basics and Crystal
Selection for rfPIC® and PIC® Devices”
• AN849, “Basic PIC® Oscillator Design”
• AN943, “Practical PIC® Oscillator Analysis and
Design”
• AN949, “Making Your Oscillator Work”
See the notes following Table 3- 3 for additional
information.
Osc Type Crystal
Freq.
Typical Cap acitor Values
Tested:
C1 C2
HS 4 MHz 27 pF 27 pF
8 MHz 22 pF 22 pF
20 MHz 15 pF 15 pF
Capacitor values are for design guidance only.
Different capacitor values may be required to produce
acceptable oscillator operation. The user should test
the performance of the oscillator over the expected
VDD and temperature range for the application.
Refer to the Microchip application notes cited in
Table 3-2 for oscillator-specific information. Also see
the notes following this table for additional
information.
Note 1: Higher capacitance increases the stability
of THE oscillator but also increases the
start-up time.
2: Since each resonator/crystal has its own
characteristics, the user should consult
the resonator/crystal manufacturer for
appropriate values of external
components.
3: Rs may be required to avoid overdriving
crystals with a low drive level specification.
4: Always verify oscillator performance over
the VDD and temperature range that is
expected for the application.
Note 1: See Ta b le 3 - 2 and Table 3-3 for initial values of
C1 and C2.
2: A series resistor (RS) may be required for AT
strip cut crystals.
3: RF varies with the oscillator mode chosen.
C1(1)
C2(1)
XTAL
OSC2
OSC1
RF(3)
Sleep
To
Logic
RS(2)
Internal
PIC18F87K22
2011 Microchip Technology Inc. DS39960C-page 51
PIC18F87K22 FAMILY
3.5.2 EXTERNAL CLOCK INPUT
(EC MODES)
The EC and ECPLL Oscillator modes require an
external clock source to be connected to the OSC1 pin.
There is no oscillator start-up time required after a
Power-on Reset or after an exit from Sleep mode.
In the EC Oscillator mode, the oscillator frequency
divided by 4 is available on the OSC2 pin. This signal
may be used for test purposes or to synchronize other
logic. Figure 3-5 shows the pin connections for the EC
Oscillator mode.
FIGURE 3-5: EXTERNAL CLOCK
INPUT OPERATION
(EC CONFIGURATION)
An external clock source may also be connected to the
OSC1 pin in HS mode, as shown in Figure 3-6. In this
configuration, the divide-by-4 output on OSC2 is not
available. Current consumption in this configuration will
be somewhat higher than EC mode, as the internal
oscillator’s feedback circuitry will be enabled (in EC
mode, the feedback circuit is disabled).
FIGURE 3-6: EXTER NAL CLOCK INPUT
OPERATION (HS OSC
CONFIGURATION)
3.5.3 PLL FREQUENCY MULTIPLIER
A Phase Locked Loop (PLL) circuit is provided as an
option for users who want to use a lower frequency
oscillator circuit, or to clock the device up to its highest
rated frequency from a crystal oscillator. This may be
useful for customers who are concerned with EMI due
to high-frequency crystals, or users who require higher
clock speeds from an internal oscillator.
3.5.3.1 HSPLL and ECPLL Modes
The HSPLL and ECPLL modes provide the ability to
selectively run the device at four times the external
oscillating source to produce frequencies up to
64 MHz.
The PLL is enabled by setting the PLLEN bit
(OSCTUNE<6>) or the PLLCFG bit (CONFIG1H<4>).
For the HF-INTOSC as primary, the PLL must be
enabled with the PLLEN. This provides a software con-
trol for the PLL, enabling even if PLLCFG is set to ‘1’,
so that the PLL is enabled only when the HF-INTOSC
frequency is within the 4 MHz to16 MHz input range.
This also enables additional flexibility for controlling the
application’s clock speed in software. The PLLEN
should be enabled in HF-INTOSC mode only if the
input frequency is in the range of 4 MHz-16 MHz.
FIGURE 3-7: PLL BLOCK DIAGRAM
3.5.3.2 PLL and HF-INTOSC
The PLL is available to the internal oscillator block
when the internal oscillator block is configured as the
primary clock source. In this configuration, the PLL is
enabled in software and generates a clock output of up
to 64 MHz.
The operation of INTOSC with the PLL is described in
Section 3.6.2 “INTPLL Modes”. Care should be taken
that the PLL is enabled only if the HF-INTOSC
postscaler is configured for 4 MHz, 8 MHz or 16 MHz.
OSC1/CLKI
OSC2/CLKO
FOSC/4
Clock from
Ext. System PIC18F87K22
OSC1
OSC2
Open
Clock from
Ext. System
(HS Mode)
PIC18F87K22
MUX
VCO
Loop
Filter
OSC2
OSC1
PLL Enable (OSCTUNE)
FIN
FOUT
SYSCLK
Phase
Comparator
PLLCFG (CONFIG1H<4>)
4
HS or EC
Mode
PIC18F87K22 FAMILY
DS39960C-page 52 2011 Microchip Technology Inc.
3.6 Internal Oscillator Block
The PIC18F87K22 family of devices includes an internal
oscillator block which generates two different clock
signals. Either clock can be used as the microcontroller’s
clock source, which may eliminate the need for an
external oscillator circuit on the OSC1 and/or OSC2 pins.
The internal oscillator consists of three blocks,
depending on the frequency of operation. They are
HF-INTOSC, MF-INTOSC and LF-INTRC.
In HF-INTOSC mode, the internal oscillator can provide
a frequency ranging from 31 KHz to 16 MHz, with the
postscaler deciding the selected frequency
(IRCF<2:0>).
The INTSRC bit (OSCTUNE<7>) and MFIOSEL bit
(OSCCON2<0>) also decide which INTOSC provides
the lower frequency (500 kHz to 31 KHz). For the
HF-INTOSC to provide these frequencies, INTSRC = 1
and MFIOSEL = 0.
In HF-INTOSC, the postscaler (IRCF<2:0>) provides
the frequency range of 31 kHz to 16 MHz. If
HF-INTOSC is used with the PLL, the input frequency
to the PLL should be 4 MHz to 16 MHz
(IRCF<2:0> = 111, 110 or 101).
For MF-INTOSC mode to provide a frequency range of
500 kHz to 31 kHz, INTSRC = 1 and MFIOSEL = 1.
The postscaler (IRCF<2:0>), in this mode, provides the
frequency range of 31 kHz to 500 kHz.
The LF-INTRC can provide only 31 kHz if INTSRC = 0.
The LF-INTRC provides 31 kHz and is enabled if it is
selected as the device clock source. The mode is
enabled automatically when any of the following are
enabled:
• Power-up Timer
• Fail-Safe Clock Monitor
• Watchdog Timer
• Two-Speed Start-up
These features are discussed in greater detail in
Section 28.0 “Special Features of the CPU”.
The clock source frequency (HF-INTOSC, MF-INTOSC
or LF-INTRC direct) is selected by configuring the IRCF
bits of the OSCCON register, as well the INTSRC and
MFIOSEL bits. The default frequency on device Resets
is 8 MHz.
3.6.1 INTIO MODES
Using the internal oscillator as the clock source elimi-
nates the need for up to two external oscillator pins,
which can then be used for digital I/O. Two distinct
oscillator configurations, which are determined by the
FOSC Configuration bits, are available:
• In INTIO1 mode, the OSC2 pin (RA6) outputs
FOSC/4, while OSC1 functions as RA7 (see
Figure 3-8) for digital input and output.
• In INTIO2 mode, OSC1 functions as RA7 and
OSC2 functions as RA6 (see Figure 3-9). Both
are available as digital input and output ports.
FIGURE 3-8: INTIO1 OSCILLATOR MODE
FIGURE 3-9: INTIO2 OSCILLATOR MODE
3.6.2 INTPLL MODES
The 4x Phase Lock Loop (PLL) can be used with the
HF-INTOSC to produce faster device clock speeds
than are normally possible with the internal oscillator
sources. When enabled, the PLL produces a clock
speed of 16 MHz or 64 MHz.
PLL operation is controlled through software. The
control bits, PLLEN (OSCTUNE<6>) and PLLCFG
(CONFIG1H<4>), are used to enable or disable its
operation. The PLL is available only to HF-INTOSC.
The other oscillator is set with HS and EC modes. Addi-
tionally, the PLL will only function when the selected
output frequency is either 4 MHz or 16 MHz
(OSCCON<6:4> = 111, 110 or 101).
Like the INTIO modes, there are two distinct INTPLL
modes available:
• In INTPLL1 mode, the OSC2 pin outputs FOSC/4,
while OSC1 functions as RA7 for digital input and
output. Externally, this is identical in appearance
to INTIO1 (Figure 3-8).
• In INTPLL2 mode, OSC1 functions as RA7 and
OSC2 functions as RA6, both for digital input and
output. Externally, this is identical to INTIO2
(Figure 3-9).
OSC2
FOSC/4
I/O (OSC1)
RA7
PIC18F87K22
I/O (OSC2)
RA6
I/O (OSC1)
RA7
PIC18F87K22
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3.6.3 INTERNAL OSCILLATOR OUTPUT
FREQUENCY AND TUNING
The internal oscillator block is calibrated at the factory
to produce an INTOSC output frequency of 16 MHz. It
can be adjusted in the user’s application by writing to
TUN<5:0> (OSCTUNE<5:0>) in the OSCTUNE
register (Register 3-3).
When the OSCTUNE register is modified, the INTOSC
(HF-INTOSC and MF-INTOSC) frequency will begin
shifting to the new frequency. The oscillator will require
some time to stabilize. Code execution continues
during this shift and there is no indication that the shift
has occurred.
The LF-INTOSC oscillator operates independently of
the HF-INTOSC or the MF-INTOSC source. Any
changes in the HF-INTOSC or the MF-INTOSC source,
across voltage and temperature, are not necessarily
reflected by changes in LF-INTOSC or vice versa. The
frequency of LF-INTOSC is not affected by OSCTUNE.
3.6.4 INTOSC FREQUENCY DRIFT
The INTOSC frequency may drift as VDD or tempera-
ture changes, and can affect the controller operation in
a variety of ways. It is possible to adjust the INTOSC
frequency by modifying the value in the OSCTUNE
register. Depending on the device, this may have no
effect on the LF-INTOSC clock source frequency.
Tuning INTOSC requires knowing when to make the
adjustment, in which direction it should be made, and in
some cases, how large a change is needed. Three
compensation techniques are shown here.
3.6.4.1 Compensating with the EUSART
An adjustment may be required when the EUSART
begins to generate framing errors or receives data with
errors while in Asynchronous mode. Framing errors indi-
cate that the device clock frequency is too high. To adjust
for this, decrement the value in OSCTUNE to reduce the
clock frequency. On the other hand, errors in data may
suggest that the clock speed is too low. To compensate,
increment OSCTUNE to increase the clock frequency.
3.6.4.2 Compensating with the Timers
This technique compares device clock speed to some
reference clock. Two timers may be used; one timer is
clocked by the peripheral clock, while the other is clocked
by a fixed reference source, such as the SOSC oscillator.
Both timers are cleared, but the timer clocked by the
reference generates interrupts. When an interrupt
occurs, the internally clocked timer is read and both
timers are cleared. If the internally clocked timer value
is much greater than expected, then the internal
oscillator block is running too fast. To adjust for this,
decrement the OSCTUNE register.
3.6.4.3 Compensating with the CCP Module
in Capture Mode
A CCP module can use free-running Timer1 (or
Timer3), clocked by the internal oscillator block and an
external event with a known period (i.e., AC power
frequency). The time of the first event is captured in the
CCPRxH:CCPRxL registers and is recorded for use
later. When the second event causes a capture, the
time of the first event is subtracted from the time of the
second event. Since the period of the external event is
known, the time difference between events can be
calculated.
If the measured time is much greater than the
calculated time, the internal oscillator block is running
too fast. To compensate, decrement the OSCTUNE
register. If the measured time is much less than the
calculated time, the internal oscillator block is running
too slow. To compensate, increment the OSCTUNE
register.
3.7 Reference Clock Output
In addition to the FOSC/4 clock output, in certain
oscillator modes, the device clock in the PIC18F87K22
family can also be configured to provide a reference
clock output signal to a port pin. This feature is avail-
able in all oscillator configurations and allows the user
to select a greater range of clock submultiples to drive
external devices in the application.
This reference clock output is controlled by the
REFOCON register (Register 3-4). Setting the ROON
bit (REFOCON<7>) makes the clock signal available
on the REFO (RE3) pin. The RODIV<3:0> bits enable
the selection of 16 different clock divider options.
The ROSSLP and ROSEL bits (REFOCON<5:4>) con-
trol the availability of the reference output during Sleep
mode. The ROSEL bit determines if the oscillator on
OSC1 and OSC2, or the current system clock source,
is used for the reference clock output. The ROSSLP bit
determines if the reference source is available on RE3
when the device is in Sleep mode.
To use the reference clock output in Sleep mode, both
the ROSSLP and ROSEL bits must be set. The device
clock must also be configured for an EC or HS mode. If
not, the oscillator on OSC1 and OSC2 will be powered
down when the device enters Sleep mode. Clearing the
ROSEL bit allows the reference output frequency to
change as the system clock changes during any clock
switches.
PIC18F87K22 FAMILY
DS39960C-page 54 2011 Microchip Technology Inc.
REGISTER 3-4: REFOCON: REFERENCE OSCILLATOR CONTROL REGISTER
R/W-0 U-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0
ROON — ROSSLP ROSEL(1) RODIV3 RODIV2 RODIV1 RODIV0
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 ROON: Reference Oscillator Output Enable bit
1 = Reference oscillator output is available on REFO pin
0 = Reference oscillator output is disabled
bit 6 Unimplemented: Read as ‘0’
bit 5 ROSSLP: Reference Oscillator Output Stop in Sleep bit
1 = Reference oscillator continues to run in Sleep
0 = Reference oscillator is disabled in Sleep
bit 4 ROSEL: Reference Oscillator Source Select bit(1)
1 = Primary oscillator (EC or HS) is used as the base clock
0 = System clock is used as the base clock; base clock reflects any clock switching of the device
bit 3-0 RODIV<3:0>: Reference Oscillator Divisor Select bits
1111 = Base clock value divided by 32,768
1110 = Base clock value divided by 16,384
1101 = Base clock value divided by 8,192
1100 = Base clock value divided by 4,096
1011 = Base clock value divided by 2,048
1010 = Base clock value divided by 1,024
1001 = Base clock value divided by 512
1000 = Base clock value divided by 256
0111 = Base clock value divided by 128
0110 = Base clock value divided by 64
0101 = Base clock value divided by 32
0100 = Base clock value divided by 16
0011 = Base clock value divided by 8
0010 = Base clock value divided by 4
0001 = Base clock value divided by 2
0000 = Base clock value
Note 1: For ROSEL (REVOCON<4>), the primary oscillator is available only when configured as the default via the
FOSC settings. This is regardless of whether the device is in Sleep mode.
2011 Microchip Technology Inc. DS39960C-page 55
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3.8 Effects of Power-Managed Modes
on the Various Clock Sources
When PRI_IDLE mode is selected, the designated pri-
mary oscillator continues to run without interruption.
For all other power-managed modes, the oscillator
using the OSC1 pin is disabled. The OSC1 pin (and
OSC2 pin if used by the oscillator) will stop oscillating.
In secondary clock modes (SEC_RUN and
SEC_IDLE), the SOSC oscillator is operating and
providing the device clock. The SOSC oscillator may
also run in all power-managed modes if required to
clock SOSC.
In RC_RUN and RC_IDLE modes, the internal
oscillator provides the device clock source. The 31 kHz
LF-INTOSC output can be used directly to provide the
clock and may be enabled to support various special
features, regardless of the power-managed mode (see
Section 28.2 “Watchdog Timer (WDT)” through
Section 28.5 “Fail-Safe Clock Monitor” for more
information on WDT, Fail-Safe Clock Monitor and
Two-Speed Start-up).
If the Sleep mode is selected, all clock sources are
stopped. Since all the transistor switching currents
have been stopped, Sleep mode achieves the lowest
current consumption of the device (only leakage
currents).
Enabling any on-chip feature that will operate during
Sleep will increase the current consumed during Sleep.
The INTOSC is required to support WDT operation.
The SOSC oscillator may be operating to support a
Real-Time Clock (RTC). Other features may be operat-
ing that do not require a device clock source (i.e.,
MSSP slave, INTx pins and others). Peripherals that
may add significant current consumption are listed in
Section 31.2 “DC Characteristics: Power-Down and
Supply Current PIC18F87K22 Family (Industrial)”.
3.9 Power-up Delays
Power-up delays are controlled by two timers, so that
no external Reset circuitry is required for most applica-
tions. The delays ensure that the device is kept in
Reset until the device power supply is stable under nor-
mal circumstances and the primary clock is operating
and stable. For additional information on power-up
delays, see Section 5.6 “Power-up Timer (PWRT)”.
The first timer is the Power-up Timer (PWRT), which
provides a fixed delay on power-up time of about 64 ms
(Parameter 33, Table 31-13); it is always enabled.
The second timer is the Oscillator Start-up Timer
(OST), intended to keep the chip in Reset until the
crystal oscillator is stable (HS, XT or LP modes). The
OST does this by counting 1,024 oscillator cycles
before allowing the oscillator to clock the device.
There is a delay of interval, T
CSD (Parameter 38,
Table 31-13), following POR, while the controller
becomes ready to execute instructions.
TABLE 3-4: OSC1 AND OSC2 PIN STATES IN SLEEP MODE
Oscillator Mode OSC1 Pin OSC2 Pin
EC, ECPLL Floating, pulled by external clock At logic low (clock/4 output)
HS, HSPLL Feedback inverter disabled at quiescent
voltage level
Feedback inverter disabled at quiescent
voltage level
INTOSC, INTPLL1/2 I/O pin, RA6, direction controlled by
TRISA<6>
I/O pin, RA6, direction controlled by
TRISA<7>
Note: See Section 5.0 “Reset” for time-outs due to Sleep and MCLR Reset.
PIC18F87K22 FAMILY
DS39960C-page 56 2011 Microchip Technology Inc.
NOTES:
2011 Microchip Technology Inc. DS39960C-page 57
PIC18F87K22 FAMILY
4.0 POWER-MANAGED MODES
The PIC18F87K22 family of devices offers a total of
seven operating modes for more efficient power man-
agement. These modes provide a variety of options for
selective power conservation in applications where
resources may be limited (such as battery-powered
devices).
There are three categories of power-managed mode:
• Run modes
• Idle modes
• Sleep mode
There is an Ultra Low-Power Wake-up (ULPWU) for
waking from the Sleep mode.
These categories define which portions of the device
are clocked, and sometimes, at what speed. The Run
and Idle modes may use any of the three available
clock sources (primary, secondary or internal oscillator
block). The Sleep mode does not use a clock source.
The ULPWU mode, on the RA0 pin, enables a slow fall-
ing voltage to generate a wake-up, even from Sleep,
without excess current consumption. (See Section 4.7
“Ultra Low-Power Wake-up”.)
The power-managed modes include several power-
saving features offered on previous PIC® devices. One
is the clock switching feature, offered in other PIC18
devices. This feature allows the controller to use the
SOSC oscillator instead of the primary one. Another
power-saving feature is Sleep mode, offered by all PIC
devices, where all device clocks are stopped.
4.1 Selecting Power-Managed Modes
Selecting a power-managed mode requires two
decisions:
• Will the CPU be clocked or not
• What will be the clock source
The IDLEN bit (OSCCON<7>) controls CPU clocking,
while the SCS<1:0> bits (OSCCON<1:0>) select the
clock source. The individual modes, bit settings, clock
sources and affected modules are summarized in
Tab l e 4-1.
4.1.1 CLOCK SOURCES
The SCS<1:0> bits select one of three clock sources
for power-managed modes. Those sources are:
• The primary clock as defined by the FOSC<3:0>
Configuration bits
• The secondary clock (the SOSC oscillator)
• The internal oscillator block (for LF-INTOSC
modes)
4.1.2 ENTERING POWER-MANAGED
MODES
Switching from one power-managed mode to another
begins by loading the OSCCON register. The
SCS<1:0> bits select the clock source and determine
which Run or Idle mode is used. Changing these bits
causes an immediate switch to the new clock source,
assuming that it is running. The switch may also be
subject to clock transition delays. These considerations
are discussed in Section 4.1.3 “Clock Transitions
and Status Indicators” and subsequent sections.
Entering the power-managed Idle or Sleep modes is
triggered by the execution of a SLEEP instruction. The
actual mode that results depends on the status of the
IDLEN bit.
Depending on the current and impending mode, a
change to a power-managed mode does not always
require setting all of the previously discussed bits. Many
transitions can be done by changing the oscillator select
bits, or changing the IDLEN bit, prior to issuing a SLEEP
instruction. If the IDLEN bit is already configured as
desired, it may only be necessary to perform a SLEEP
instruction to switch to the desired mode.
TABLE 4-1: POWER-MANAGED MODE S
Mode OSCCON Bits Module Clocking Available Clock and Oscillator Source
IDLEN<7>(1) SCS<1:0> CPU Peripherals
Sleep 0N/A Off Off None – All clocks are disabled
PRI_RUN N/A 00 Clocked Clocked Primary – XT, LP, HS, EC, RC and PLL modes.
This is the normal, full-power execution mode.
SEC_RUN N/A 01 Clocked Clocked Secondary – SOSC Oscillator
RC_RUN N/A 1x Clocked Clocked Internal oscillator block(2)
PRI_IDLE 100Off Clocked Primary – LP, XT, HS, RC, EC
SEC_IDLE 101Off Clocked Secondary – SOSC oscillator
RC_IDLE 11xOff Clocked Internal oscillator block(2)
Note 1: IDLEN reflects its value when the SLEEP instruction is executed.
2: Includes INTOSC (HF-INTOSC and MG-INTOSC) and INTOSC postscaler, as well as the LF-INTOSC
source.
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DS39960C-page 58 2011 Microchip Technology Inc.
4.1.3 CLOCK TRANSITIONS AND STATUS
INDICATORS
The length of the transition between clock sources is
the sum of two cycles of the old clock source and
three to four cycles of the new clock source. This for-
mula assumes that the new clock source is stable.
The HF-INTOSC and MF-INTOSC are termed as
INTOSC in this chapter.
Three bits indicate the current clock source and its
status, as shown in Table 4- 2. The three bits are:
• OSTS (OSCCON<3>)
• HFIOFS (OSCCON<2>)
• SOSCRUN (OSCCON2<6>)
When the OSTS bit is set, the primary clock is providing
the device clock. When the HFIOFS or MFIOFS bit is
set, the INTOSC output is providing a stable 16 MHz
clock source to a divider that actually drives the device
clock. When the SOSCRUN bit is set, the SOSC oscil-
lator is providing the clock. If none of these bits are set,
either the LF-INTOSC clock source is clocking the
device or the INTOSC source is not yet stable.
If the internal oscillator block is configured as the
primary clock source by the FOSC<3:0> Configuration
bits (CONFIG1H<3:0>), then the OSTS and HFIOFS or
MFIOFS bits can be set when in PRI_RUN or
PRI_IDLE modes. This indicates that the primary clock
(INTOSC output) is generating a stable 16 MHz output.
Entering another INTOSC power-managed mode at
the same frequency would clear the OSTS bit.
4.1.4 MULTIPLE SLEEP COMMANDS
The power-managed mode that is invoked with the
SLEEP instruction is determined by the setting of the
IDLEN bit at the time the instruction is executed. If
another SLEEP instruction is executed, the device will
enter the power-managed mode specified by IDLEN at
that time. If IDLEN has changed, the device will enter
the new power-managed mode specified by the new
setting.
4.2 Run Modes
In the Run modes, clocks to both the core and
peripherals are active. The difference between these
modes is the clock source.
4.2.1 PRI_RUN MODE
The PRI_RUN mode is the normal, full-power execu-
tion mode of the microcontroller. This is also the default
mode upon a device Reset, unless Two-Speed Start-up
is enabled. (For details, see Section 28.4 “T wo-Speed
Start-up”.) In this mode, the OSTS bit is set. The
HFIOFS or MFIOFS bit may be set if the internal
oscillator block is the primary clock source. (See
Section 3.2 “Control Registers”.)
4.2.2 SEC_RUN MODE
The SEC_RUN mode is the compatible mode to the
“clock-switching” feature offered in other PIC18
devices. In this mode, the CPU and peripherals are
clocked from the SOSC oscillator. This enables lower
power consumption while retaining a high-accuracy
clock source.
SEC_RUN mode is entered by setting the SCS<1:0>
bits to ‘01’. The device clock source is switched to the
SOSC oscillator (see Figure 4-1), the primary oscillator
is shut down, the SOSCRUN bit (OSCCON2<6>) is set
and the OSTS bit is cleared.
On transitions from SEC_RUN mode to PRI_RUN
mode, the peripherals and CPU continue to be clocked
from the SOSC oscillator while the primary clock is
started. When the primary clock becomes ready, a
clock switch back to the primary clock occurs (see
Figure 4-2). When the clock switch is complete, the
SOSCRUN bit is cleared, the OSTS bit is set and the
primary clock is providing the clock. The IDLEN and
SCS bits are not affected by the wake-up and the
SOSC oscillator continues to run.
TABLE 4-2: SYSTEM CLOCK INDICATOR
Main Clock Source OSTS HFIOFS or
MFIOFS SOSCRUN
Primary Oscillator 10 0
INTOSC (HF-INTOSC or
MF-INTOSC) 01 0
Secondary Oscillator 00 1
MF-INTOSC or
HF-INTOSC as Primary
Clock Source
11 0
LF-INTOSC is Running or
INTOSC is Not Yet Stable 00 0
Note 1: Caution should be used when modifying
a single IRCF bit. At a lower VDD, it is
possible to select a higher clock speed
than is supportable by that VDD. Improper
device operation may result if the VDD/
FOSC specifications are violated.
2: Executing a SLEEP instruction does not
necessarily place the device into Sleep
mode. It acts as the trigger to place the
controller into either the Sleep mode or
one of the Idle modes, depending on the
setting of the IDLEN bit.
Note: The SOSC oscillator can be enabled by
setting the SOSCGO bit (OSCCON2<3>).
If this bit is set, the clock switch to the
SEC_RUN mode can switch immediately
once SCS<1:0> are set to ‘01’.
2011 Microchip Technology Inc. DS39960C-page 59
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FIGURE 4-1: TRANSITION TIMING FOR ENTRY TO SEC_RUN MODE
FIGURE 4-2: TRANSITION TIMING FROM SEC_RUN MODE TO PRI_RUN MODE (HSPLL)
Q4Q3Q2
OSC1
Peripheral
Program
Q1
SOSCI
Q1
Counter
Clock
CPU
Clock
PC + 2PC
123 n-1n
Clock Transition(1)
Q4Q3Q2 Q1 Q3Q2
PC + 4
Note 1: Clock transition typically occurs within 2-4 TOSC.
Q1 Q3 Q4
OSC1
Peripheral
Program PC
SOSC
PLL Clock
Q1
PC + 4
Q2
Output
Q3 Q4 Q1
CPU Clock
PC + 2
Clock
Counter
Q2 Q2 Q3
Note1:TOST = 1024 TOSC; TPLL = 2 ms (approx). These intervals are not shown to scale.
2: Clock transition typically occurs within 2-4 TOSC.
SCS<1:0> bits Changed
TPLL(1)
12 n-1n
Clock
OSTS bit Set
Transition(2)
TOST(1)
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4.2.3 RC_RUN MODE
In RC_RUN mode, the CPU and peripherals are
clocked from the internal oscillator block using the
INTOSC multiplexer. In this mode, the primary clock is
shut down. When using the LF-INTOSC source, this
mode provides the best power conservation of all the
Run modes, while still executing code. It works well for
user applications which are not highly timing-sensitive
or do not require high-speed clocks at all times.
If the primary clock source is the internal oscillator
block – either LF-INTOSC or INTOSC (MF-INTOSC or
HF-INTOSC) – there are no distinguishable differences
between the PRI_RUN and RC_RUN modes during
execution. Entering or exiting RC_RUN mode, how-
ever, causes a clock switch delay. Therefore, if the
primary clock source is the internal oscillator block,
using RC_RUN mode is not recommended.
This mode is entered by setting the SCS1 bit to ‘1’. To
maintain software compatibility with future devices, it is
recommended that the SCS0 bit also be cleared, even
though the bit is ignored. When the clock source is
switched to the INTOSC multiplexer (see Figure 4-3),
the primary oscillator is shut down and the OSTS bit is
cleared. The IRCF bits may be modified at any time to
immediately change the clock speed.
If the IRCF bits and the INTSRC bit are all clear, the
INTOSC output (HF-INTOSC/MF-INTOSC) is not
enabled and the HFIOFS and MFIOFS bits will remain
clear. There will be no indication of the current clock
source. The LF-INTOSC source is providing the device
clocks.
If the IRCF bits are changed from all clear (thus,
enabling the INTOSC output) or if INTSRC or
MFIOSEL is set, the HFIOFS or MFIOFS bit is set after
the INTOSC output becomes stable. For details, see
Table 4-3.
TABLE 4-3: INTERNAL OSCILLATOR FREQUENCY STABILITY BITS
Note: Caution should be used when modifying a
single IRCF bit. At a lower VDD, it is
possible to select a higher clock speed
than is supportable by that VDD. Improper
device operation may result if the VDD/
FOSC specifications are violated.
IRCF<2:0> INTSRC MFIOSEL Status of MFIOFS or HFIOFS when INTOSC is Stable
000 0 x MFIOFS = 0, HFIOFS = 0 and clock source is LF-INTOSC
000 1 0 MFIOFS = 0, HFIOFS = 1 and clock source is HF-INTOSC
000 1 1 MFIOFS = 1, HFIOFS = 0 and clock source is MF-INTOSC
Non-Zero x0MFIOFS = 0, HFIOFS = 1 and clock source is HF-INTOSC
Non-Zero x1MFIOFS = 1, HFIOFS = 0 and clock source is MF-INTOSC
2011 Microchip Technology Inc. DS39960C-page 61
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Clocks to the device continue while the INTOSC source
stabilizes after an interval of TIOBST (Parameter 39,
Table 31-13).
If the IRCF bits were previously at a non-zero value, or
if INTSRC was set before setting SCS1 and the
INTOSC source was already stable, the HFIOFS or
MFIOFS bit will remain set.
On transitions from RC_RUN mode to PRI_RUN mode,
the device continues to be clocked from the INTOSC
multiplexer while the primary clock is started. When the
primary clock becomes ready, a clock switch to the
primary clock occurs (see Figure 4-4). When the clock
switch is complete, the HFIOFS or MFIOFS bit is
cleared, the OSTS bit is set and the primary clock is
providing the device clock. The IDLEN and SCS bits
are not affected by the switch. The LF-INTOSC source
will continue to run if either the WDT or the Fail-Safe
Clock Monitor is enabled.
FIGURE 4-3: TRANSITION TIMING TO RC_RUN MODE
FIGURE 4-4: TRANSITION TIMING FROM RC_RUN MODE TO PRI_RUN MODE
Q4Q3Q2
OSC1
Peripheral
Program
Q1
LF-INTOSC
Q1
Counter
Clock
CPU
Clock
PC + 2PC
123 n-1n
Clock Transition(1)
Q4Q3Q2 Q1 Q3Q2
PC + 4
Note 1: Clock transition typically occurs within 2-4 TOSC.
Q1 Q3 Q4
OSC1
Peripheral
Program PC
INTOSC
PLL Clock
Q1
PC + 4
Q2
Output
Q3 Q4 Q1
CPU Clock
PC + 2
Clock
Counter
Q2 Q2 Q3
Note 1: TOST = 1024 TOSC; TPLL = 2 ms (approx). These intervals are not shown to scale.
2: Clock transition typically occurs within 2-4 TOSC.
SCS<1:0> bits Changed
TPLL(1)
12 n-1n
Clock
OSTS bit Set
Transition(2)
Multiplexer
TOST(1)
PIC18F87K22 FAMILY
DS39960C-page 62 2011 Microchip Technology Inc.
4.3 Sleep Mode
The power-managed Sleep mode in the PIC18F87K22
family of devices is identical to the legacy Sleep mode
offered in all other PIC devices. It is entered by clearing
the IDLEN bit (the default state on device Reset) and
executing the SLEEP instruction. This shuts down the
selected oscillator (Figure 4-5). All clock source status
bits are cleared.
Entering Sleep mode from any other mode does not
require a clock switch. This is because no clocks are
needed once the controller has entered Sleep. If the
WDT is selected, the LF-INTOSC source will continue
to operate. If the SOSC oscillator is enabled, it will also
continue to run.
When a wake event occurs in Sleep mode (by interrupt,
Reset or WDT time-out), the device will not be clocked
until the clock source selected by the SCS<1:0> bits
becomes ready (see Figure 4-6). Alternately, the device
will be clocked from the internal oscillator block if either
the Two-Speed Start-up or the Fail-Safe Clock Monitor is
enabled (see Section 28.0 “Special Features of the
CPU”). In either case, the OSTS bit is set when the
primary clock is providing the device clocks. The IDLEN
and SCS bits are not affected by the wake-up.
4.4 Idle Modes
The Idle modes allow the controller’s CPU to be
selectively shut down while the peripherals continue to
operate. Selecting a particular Idle mode allows users
to further manage power consumption.
If the IDLEN bit is set to a ‘1’ when a SLEEP instruction is
executed, the peripherals will be clocked from the clock
source selected using the SCS<1:0> bits. The CPU,
however, will not be clocked. The clock source status bits
are not affected. This approach is a quick method to
switch from a given Run mode to its corresponding Idle
mode.
If the WDT is selected, the LF-INTOSC source will
continue to operate. If the SOSC oscillator is enabled,
it will also continue to run.
Since the CPU is not executing instructions, the only
exits from any of the Idle modes are by interrupt, WDT
time-out or a Reset. When a wake event occurs, CPU
execution is delayed by an interval of T
CSD
(Parameter 38, Table 31-13) while it becomes ready to
execute code. When the CPU begins executing code,
it resumes with the same clock source for the current
Idle mode. For example, when waking from RC_IDLE
mode, the internal oscillator block will clock the CPU
and peripherals (in other words, RC_RUN mode). The
IDLEN and SCS bits are not affected by the wake-up.
While in any Idle mode or Sleep mode, a WDT time-
out will result in a WDT wake-up to the Run mode
currently specified by the SCS<1:0> bits.
FIGURE 4-5: TRANSITION TIMING FOR ENTRY TO SLEEP MODE
FIGURE 4-6: TRANSITION TIMING FOR WAKE FROM SLEEP (HSPLL)
Q4Q3Q2
OSC1
Peripheral
Sleep
Program
Q1Q1
Counter
Clock
CPU
Clock
PC + 2PC
Q3 Q4 Q1 Q2
OSC1
Peripheral
Program PC
PLL Clock
Q3 Q4
Output
CPU Clock
Q1 Q2 Q3 Q4 Q1 Q2
Clock
Counter PC + 6
PC + 4
Q1 Q2 Q3 Q4
Wake Event
Note 1: TOST = 1024 TOSC; TPLL = 2 ms (approx). These intervals are not shown to scale.
TOST(1) TPLL(1)
OSTS bit Set
PC + 2
2011 Microchip Technology Inc. DS39960C-page 63
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4.4.1 PRI_IDLE MODE
This mode is unique among the three low-power Idle
modes, in that it does not disable the primary device
clock. For timing-sensitive applications, this allows for
the fastest resumption of device operation with its more
accurate, primary clock source, since the clock source
does not have to “warm-up” or transition from another
oscillator.
PRI_IDLE mode is entered from PRI_RUN mode by
setting the IDLEN bit and executing a SLEEP instruc-
tion. If the device is in another Run mode, set IDLEN
first, then clear the SCS bits and execute SLEEP.
Although the CPU is disabled, the peripherals continue
to be clocked from the primary clock source specified
by the FOSC<3:0> Configuration bits. The OSTS bit
remains set (see Figure 4-7).
When a wake event occurs, the CPU is clocked from the
primary clock source. A delay of interval, TCSD
(Parameter 39, Table 31-13), is required between the
wake event and the start of code execution. This is
required to allow the CPU to become ready to execute
instructions. After the wake-up, the OSTS bit remains
set. The IDLEN and SCS bits are not affected by the
wake-up (see Figure 4-8).
4.4.2 SEC_IDLE MODE
In SEC_IDLE mode, the CPU is disabled but the
peripherals continue to be clocked from the SOSC
oscillator. This mode is entered from SEC_RUN by set-
ting the IDLEN bit and executing a SLEEP instruction. If
the device is in another Run mode, set the IDLEN bit
first, then set the SCS<1:0> bits to ‘01’ and execute
SLEEP. When the clock source is switched to the SOSC
oscillator, the primary oscillator is shut down, the OSTS
bit is cleared and the SOSCRUN bit is set.
When a wake event occurs, the peripherals continue to
be clocked from the SOSC oscillator. After an interval
of T
CSD following the wake event, the CPU begins
executing code being clocked by the SOSC oscillator.
The IDLEN and SCS bits are not affected by the wake-
up and the SOSC oscillator continues to run (see
Figure 4-8).
FIGURE 4-7: TRANSITION TIMING FOR ENTRY TO IDLE MODE
FIGURE 4-8: TRANSITION TIMING FOR WAKE FROM IDLE TO RUN MODE
Q1
Peripheral
Program PC PC + 2
OSC1
Q3 Q4 Q1
CPU Clock
Clock
Counter
Q2
OSC1
Peripheral
Program PC
CPU Clock
Q1 Q3 Q4
Clock
Counter
Q2
Wake Event
TCSD
PIC18F87K22 FAMILY
DS39960C-page 64 2011 Microchip Technology Inc.
4.4.3 RC_IDLE MODE
In RC_IDLE mode, the CPU is disabled but the periph-
erals continue to be clocked from the internal oscillator
block using the INTOSC multiplexer. This mode
provides controllable power conservation during Idle
periods.
From RC_RUN, this mode is entered by setting the
IDLEN bit and executing a SLEEP instruction. If the
device is in another Run mode, first set IDLEN, then set
the SCS1 bit and execute SLEEP. To maintain software
compatibility with future devices, it is recommended
that SCS0 also be cleared, though its value is ignored.
The INTOSC multiplexer may be used to select a
higher clock frequency by modifying the IRCF bits
before executing the SLEEP instruction. When the
clock source is switched to the INTOSC multiplexer, the
primary oscillator is shut down and the OSTS bit is
cleared.
If the IRCF bits are set to any non-zero value, or the
INTSRC/MFIOSEL bit is set, the INTOSC output is
enabled. The HFIOFS/MFIOFS bits become set, after
the INTOSC output becomes stable, after an interval of
TIOBST (Parameter 38, Table 31-13). (For information
on the HFIOFS/MFIOFS bits, see Table 4-3.)
Clocks to the peripherals continue while the INTOSC
source stabilizes. The HFIOFS/MFIOFS bits will
remain set if the IRCF bits were previously at a non-
zero value or if INTSRC was set before the SLEEP
instruction was executed and the INTOSC source was
already stable. If the IRCF bits and INTSRC are all
clear, the INTOSC output will not be enabled, the
HFIOFS/MFIOFS bits will remain clear and there will be
no indication of the current clock source.
When a wake event occurs, the peripherals continue to
be clocked from the INTOSC multiplexer. After a delay
of TCSD (Parameter 38, Table 31-13) following the
wake event, the CPU begins executing code clocked
by the INTOSC multiplexer. The IDLEN and SCS bits
are not affected by the wake-up. The INTRC source will
continue to run if either the WDT or the Fail-Safe Clock
Monitor is enabled.
4.5 Selective Peripheral Module
Control
Idle mode allows users to substantially reduce power
consumption by stopping the CPU clock. Even so,
peripheral modules still remain clocked, and thus, con-
sume power. There may be cases where the applica-
tion needs what this mode does not provide: the
allocation of power resources to the CPU processing
with minimal power consumption from the peripherals.
PIC18F87K22 family devices address this requirement
by allowing peripheral modules to be selectively
disabled, reducing or eliminating their power
consumption. This can be done with two control bits:
• Peripheral Enable bit, generically named XXXEN –
Located in the respective module’s main control
register
• Peripheral Module Disable (PMD) bit, generically
named, XXXMD – Located in one of the PMDx
Control registers (PMD0, PMD1, PMD2 or PMD3)
Disabling a module by clearing its XXXEN bit disables
the module’s functionality, but leaves its registers
available to be read and written to. This reduces power
consumption, but not by as much as the second
approach.
Most peripheral modules have an enable bit.
In contrast, setting the PMD bit for a module disables
all clock sources to that module, reducing its power
consumption to an absolute minimum. In this state, the
control and status registers associated with the periph-
eral are also disabled, so writes to those registers have
no effect and read values are invalid. Many peripheral
modules have a corresponding PMD bit.
There are four PMD registers in the PIC18F87K22 family
devices: PMD0, PMD1, PMD2 and PMD3. These
registers have bits associated with each module for
disabling or enabling a particular peripheral.
2011 Microchip Technology Inc. DS39960C-page 65
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REGISTER 4-1: PMD3: PERIPHERAL MODULE DISABLE REGISTER 3
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0
CCP10MD(1) CCP9MD(1) CCP8MD CCP7MD CCP6MD CCP5MD CCP4MD TMR12MD(1)
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 CCP10MD: PMD CCP10 Enable/Disable bit(1)
1 = Peripheral Module Disable (PMD) is enabled for CCP10, disabling all of its clock sources
0 = PMD is disabled for CCP10
bit 6 CCP9MD: PMD CCP9 Enable/Disable bit(1)
1 = Peripheral Module Disable (PMD) is enabled for CCP9, disabling all of its clock sources
0 = PMD is disabled for CCP9
bit 5 CCP8MD: PMD CCP8 Enable/Disable bit
1 = Peripheral Module Disable (PMD) is enabled for CCP8, disabling all of its clock sources
0 = PMD is disabled for CCP8
bit 4 CCP7MD: PMD CCP7 Enable/Disable bit
1 = Peripheral Module Disable (PMD) is enabled for CCP7, disabling all of its clock sources
0 = PMD is disabled for CCP7
bit 3 CCP6MD: PMD CCP6 Enable/Disable bit
1 = Peripheral Module Disable (PMD) is enabled for CCP6, disabling all of its clock sources
0 = PMD is disabled for CCP6
bit 2 CCP5MD: PMD CCP5 Enable/Disable bit
1 = Peripheral Module Disable (PMD) is enabled for CCP5, disabling all of its clock sources
0 = PMD is disabled for CCP5
bit 1 CCP4MD: PMD CCP4 Enable/Disable bit
1 = Peripheral Module Disable (PMD) is enabled for CCP4, disabling all of its clock sources
0 = PMD is disabled for CCP4
bit 0 TMR12MD: TMR12MD Disable bit(1)
1 = PMD is enabled and all TMR12MD clock sources are disabled
0 = PMD is disabled and TMR12MD is enabled
Note 1: Unimplemented on devices with a program memory of 32 Kbytes (PIC18FX5K22).
PIC18F87K22 FAMILY
DS39960C-page 66 2011 Microchip Technology Inc.
REGISTER 4-2: PMD2: PERIPHERAL MODULE DISABLE REGISTER 2
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0
TMR10MD(1) TMR8MD TMR7MD(1) TMR6MD TMR5MD CMP3MD CMP2MD CMP1MD
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 TMR10MD: TMR10MD Disable bit(1)
1 = Peripheral Module Disable (PMD) is enabled and all TMR10MD clock sources are disabled
0 = PMD is disabled and TMR10MD is enabled
bit 6 TMR8MD: TMR8MD Disable bit
1 = PMD is enabled and all TMR8MD clock sources are disabled
0 = PMD is disabled and TMR8MD is enabled
bit 5 TMR7MD: TMR7MD Disable bit(1)
1 = PMD is enabled and all TMR7MD clock sources are disabled
0 = PMD is disabled and TMR7MD is enabled
bit 4 TMR6MD: TMR6MD Disable bit
1 = PMD is enabled and all TMR6MD clock sources are disabled
0 = PMD is disabled and TMR6MD is enabled
bit 3 TMR5MD: TMR5MD Disable bit
1 = PMD is enabled and all TMR5MD clock sources are disabled
0 = PMD is disabled and TMR5MD is enabled
bit 2 CMP3MD: PMD Comparator 3 Enable/Disable bit
1 = PMD is enabled for Comparator 3, disabling all of its clock sources
0 = PMD is disabled for Comparator 3
bit 1 CMP2MD: PMD Comparator 3 Enable/Disable bit
1 = PMD is enabled for Comparator 2, disabling all of its clock sources
0 = PMD is disabled for Comparator 2
bit 0 CMP1MD: PMD Comparator 3 Enable/Disable bit
1 = PMD is enabled for Comparator 1, disabling all of its clock sources
0 = PMD is disabled for Comparator 1
Note 1: Unimplemented on devices with a program memory of 32 Kbytes (PIC18FX5K22).
2011 Microchip Technology Inc. DS39960C-page 67
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REGISTER 4-3: PMD1: PERIPHERAL MODULE DISABLE REGISTER 1
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0
PSPMD CTMUMD RTCCMD(1) TMR4MD TMR3MD TMR2MD TMR1MD EMBMD
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 PSPMD: Peripheral Module Disable (PMD) PSP Enable/Disable bit
1 = PMD is enabled for PSP, disabling all of its clock sources
0 = PMD is disabled for PSP
bit 6 CTMUMD: PMD CTMU Enable/Disable bit
1 = PMD is enabled for CTMU, disabling all of its clock sources
0 = PMD is disabled for CTMU
bit 5 RTCCMD: PMD RTCC Enable/Disable bit(1)
1 = PMD is enabled for RTCC, disabling all of its clock sources
0 = PMD is disabled for RTCC
bit 4 TMR4MD: TMR4MD Disable bit
1 = PMD is enabled and all TMR4MD clock sources disabled
0 = PMD is disabled and TMR4MD is enabled
bit 3 TMR3MD: TMR3MD Disable bit
1 = PMD is enabled and all TMR3MD clock sources disabled
0 = PMD is disabled and TMR3MD is enabled
bit 2 TMR2MD: TMR2MD Disable bit
1 = PMD is enabled and all TMR2MD clock sources disabled
0 = PMD is disabled and TMR2MD is enabled
bit 1 TMR1MD: TMR1MD Disable bit
1 = PMD is enabled and all TMR1MD clock sources disabled
0 = PMD is disabled and TMR1MD is enabled
bit 0 EMBMD: PMD EMB Enable/Disable bit
1 = PMD is enabled for EMB, disabling all of its clock sources
0 = PMD is disabled for EMB
Note 1: RTCCMD can only be set to ‘1’ after an EECON2 unlock sequence. Refer to Section 18.0 “Real-Time
Clock and Calendar (RTCC)” for the unlock sequence (Example 18-1).
PIC18F87K22 FAMILY
DS39960C-page 68 2011 Microchip Technology Inc.
REGISTER 4-4: PMD0: PERIPHERAL MODULE DISABLE REGISTER 0
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0
CCP3MD CCP2MD CCP1MD UART2MD UART1MD SSP2MD SSP1MD ADCMD
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 CCP3MD: PMD ECCP3 Enable/Disable bit
1 = Peripheral Module Disable (PMD) is enabled for ECCP3, disabling all of its clock sources
0 = PMD is disabled for ECCP3
bit 6 CCP2MD: PMD ECCP2 Enable/Disable bit
1 = PMD is enabled for ECCP2, disabling all of its clock sources
0 = PMD is disabled for ECCP2
bit 5 CCP1MD: PMD ECCP1 Enable/Disable bit
1 = PMD is enabled for ECCP1, disabling all of its clock sources
0 = PMD is disabled for ECCP1
bit 4 UART2MD: PMD UART2 Enable/Disable bit
1 = PMD is enabled for UART2, disabling all of its clock sources
0 = PMD is disabled for UART2
bit 3 UART1MD: PMD UART1 Enable/Disable bit
1 = PMD is enabled for UART1, disabling all of its clock sources
0 = PMD is disabled for UART1
bit 2 SSP2MD: PMD MSSP2 Enable/Disable bit
1 = PMD is enabled for MSSP2, disabling all of its clock sources
0 = PMD is disabled for MSSP2
bit 1 SSP1MD: PMD MSSP1 Enable/Disable bit
1 = PMD is enabled for MSSP1, disabling all of its clock sources
0 = PMD is disabled for MSSP1
bit 0 ADCMD: PMD Analog/Digital Converter PMD Enable/Disable bit
1 = PMD is enabled for the Analog/Digital Converter, disabling all of its clock sources
0 = PMD is disabled for the Analog/Digital Converter
2011 Microchip Technology Inc. DS39960C-page 69
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4.6 Exiting Idle and Sleep Modes
An exit from Sleep mode or any of the Idle modes is
triggered by an interrupt, a Reset or a WDT time-out.
This section discusses the triggers that cause exits
from power-managed modes. The clocking subsystem
actions are discussed in each of the power-managed
modes (see Section 4.2 “Run Modes”, Section 4.3
“Sleep Mode” and Section 4.4 “Idle Modes”).
4.6.1 EXIT BY INTERRUPT
Any of the available interrupt sources can cause the
device to exit from an Idle mode or Sleep mode to a
Run mode. To enable this functionality, an interrupt
source must be enabled by setting its enable bit in one
of the INTCONx or PIEx registers. The exit sequence is
initiated when the corresponding interrupt flag bit is set.
On all exits from Idle or Sleep modes by interrupt, code
execution branches to the interrupt vector if the GIE/
GIEH bit (INTCON<7>) is set. Otherwise, code execu-
tion continues or resumes without branching (see
Section 11.0 “Interrupts”).
4.6.2 EXIT BY WDT TIME-OUT
A WDT time-out will cause different actions depending
on which power-managed mode the device is in when
the time-out occurs.
If the device is not executing code (all Idle modes and
Sleep mode), the time-out will result in an exit from the
power-managed mode (see Section 4.2 “Run
Modes” and Se ction 4.3 “Sleep Mode”). If the device
is executing code (all Run modes), the time-out will
result in a WDT Reset (see Section 28.2 “Watchdog
Timer (WDT)”).
Executing a SLEEP or CLRWDT instruction clears the
WDT timer and postscaler, loses the currently selected
clock source (if the Fail-Safe Clock Monitor is enabled)
and modifies the IRCF bits in the OSCCON register (if
the internal oscillator block is the device clock source).
4.6.3 EXIT BY RESET
Normally, the device is held in Reset by the Oscillator
Start-up Timer (OST) until the primary clock becomes
ready. At that time, the OSTS bit is set and the device
begins executing code. If the internal oscillator block is
the new clock source, the HFIOFS/MFIOFS bits are set
instead.
The exit delay time from Reset to the start of code
execution depends on both the clock sources before
and after the wake-up, and the type of oscillator, if the
new clock source is the primary clock. Exit delays are
summarized in Ta bl e 4 - 4 .
Code execution can begin before the primary clock
becomes ready. If either the Two-Speed Start-up (see
Section 28.4 “Two-Speed Start-up”) or Fail-Safe
Clock Monitor (see Section 28.5 “Fail-Safe Clock
Monitor”) is enabled, the device may begin execution
as soon as the Reset source has cleared. Execution is
clocked by the INTOSC multiplexer driven by the
internal oscillator block. Execution is clocked by the
internal oscillator block until either the primary clock
becomes ready or a power-managed mode is entered
before the primary clock becomes ready; the primary
clock is then shut down.
4.6.4 EXIT WITHOUT AN OSCILLATOR
START-UP DELAY
Certain exits from power-managed modes do not
invoke the OST at all. The two cases are:
• When in PRI_IDLE mode, where the primary
clock source is not stopped
• When the primary clock source is not any of the
LP, XT, HS or HSPLL modes
In these instances, the primary clock source either
does not require an oscillator start-up delay, since it is
already running (PRI_IDLE), or normally, does not
require an oscillator start-up delay (RC, EC and INTIO
Oscillator modes). However, a fixed delay of interval,
T
CSD, following the wake event, is still required when
leaving Sleep and Idle modes to allow the CPU to
prepare for execution. Instruction execution resumes
on the first clock cycle following this delay.
PIC18F87K22 FAMILY
DS39960C-page 70 2011 Microchip Technology Inc.
4.7 Ultra Low-Power Wake-up
The Ultra Low-Power Wake-up (ULPWU) on pin, RA0,
allows a slow falling voltage to generate an interrupt
without excess current consumption.
To use this feature:
1. Charge the capacitor on RA0 by configuring the
RA0 pin to an output and setting it to ‘1’.
2. Stop charging the capacitor by configuring RA0
as an input.
3. Discharge the capacitor by setting the ULPEN
and ULPSINK bits in the WDTCON register.
4. Configure Sleep mode.
5. Enter Sleep mode.
When the voltage on RA0 drops below VIL, the device
wakes up and executes the next instruction.
This feature provides a low-power technique for
periodically waking up the device from Sleep mode.
The time-out is dependent on the discharge time of the
RC circuit on RA0.
When the ULPWU module wakes the device from
Sleep mode, the ULPLVL bit (WDTCON<5>) is set.
Software can check this bit upon wake-up to determine
the wake-up source.
See Example 4-1 for initializing the ULPWU module.
EXAMPLE 4-1: ULTRA LOW-POWER
WAKE-UP INITIALIZATION
A series resistor, between RA0 and the external capac-
itor, provides overcurrent protection for the RA0/AN0/
ULPWU pin and enables software calibration of the
time-out (see Figure 4-9).
FIGURE 4-9: ULTRA LOW-POWER
WAKE-UP INITIALIZATION
A timer can be used to measure the charge time and
discharge time of the capacitor. The charge time can
then be adjusted to provide the desired delay in Sleep.
This technique compensates for the affects of temper-
ature, voltage and component accuracy. The peripheral
can also be configured as a simple Programmable
Low-Voltage Detect (LVD) or temperature sensor.
//***************************
//Charge the capacitor on RA0
//***************************
TRISAbits.TRISA0 = 0;
PORTAbits.RA0 = 1;
for(i = 0; i < 10000; i++) Nop();
//*****************************
//Stop Charging the capacitor
//on RA0
//*****************************
TRISAbits.TRISA0 = 1;
//*****************************
//Enable the Ultra Low Power
//Wakeup module and allow
//capacitor discharge
//*****************************
WDTCONbits.ULPEN = 1;
WDTCONbits.ULPSINK = 1;
//For Sleep
OSCCONbits.IDLEN = 0;
//Enter Sleep Mode
//
Sleep(); //for sleep, execution will
//resume here
Note: For more information, see AN879, “Using
the Microchip Ultra Low-Power Wake-up
Module” (DS00879).
RA0/AN0/ULPWU
2011 Microchip Technology Inc. DS39960C-page 71
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TABLE 4-4: EX IT DELAY ON WAKE-UP BY RESET FROM SLEEP MODE OR ANY IDLE MODE
(BY CLOCK SOURCES)
Power-Managed
Mode Clock Source(5) Exit Delay Clock Ready
Status Bits
PRI_IDLE mode
LP, XT, HS
TCSD(1)
OSTSHSPLL
EC, RC
HF-INTOSC(2) HFIOFS
MF-INTOSC(2) MFIOFS
LF-INTOSC None
SEC_IDLE mode SOSC TCSD(1) SOSCRUN
RC_IDLE mode
HF-INTOSC(2)
TCSD(1) HFIOFS
MF-INTOSC(2) MFIOFS
LF-INTOSC None
Sleep mode
LP, XT, HS TOST(3)
OSTSHSPLL TOST + trc(3)
EC, RC TCSD(1)
HF-INTOSC(2)
TIOBST(4) HFIOFS
MF-INTOSC(2) MFIOFS
LF-INTOSC None
Note 1: TCSD (Parameter 38, Table 31-13) is a required delay when waking from Sleep and all Idle modes, and
runs concurrently with any other required delays (see Section 4.4 “Idle Modes”).
2: Includes postscaler derived frequencies. On Reset, INTOSC defaults to HF-INTOSC at 8 MHz.
3: T
OST is the Oscillator Start-up Timer (Parameter 32, Table 31-13). TRC is the PLL Lock-out Timer
(Parameter F12, Table 31-7); it is also designated as TPLL.
4: Execution continues during TIOBST (Parameter 39, Table 31-13), the INTOSC stabilization period.
5: The clock source is dependent upon the settings of the SCS (OSCCON<1:0>), IRCF (OSCCON<6:4>)
and FOSC (CONFIG1H<3:0>) bits.
PIC18F87K22 FAMILY
DS39960C-page 72 2011 Microchip Technology Inc.
NOTES:
2011 Microchip Technology Inc. DS39960C-page 73
PIC18F87K22 FAMILY
5.0 RESET
The PIC18F87K22 family of devices differentiates
between various kinds of Reset:
a) Power-on Reset (POR)
b) MCLR Reset during normal operation
c) MCLR Reset during power-managed modes
d) Watchdog Timer (WDT) Reset (during
execution)
e) Configuration Mismatch (CM) Reset
f) Brown-out Reset (BOR)
g) RESET Instruction
h) Stack Full Reset
i) Stack Underflow Reset
This section discusses Resets generated by MCLR,
POR and BOR, and covers the operation of the various
start-up timers. Stack Reset events are covered in
Section 6.1.3.4 “Stack Full and Underflow Resets”.
WDT Resets are covered in Section 28.2 “Watchdog
Timer (WDT)”.
A simplified block diagram of the on-chip Reset circuit
is shown in Figure 5-1.
5.1 RCON Register
Device Reset events are tracked through the RCON
register (Register 5-1). The lower five bits of the
register indicate that a specific Reset event has
occurred. In most cases, these bits can only be set by
the event and must be cleared by the application after
the event.
The state of these flag bits, taken together, can be read
to indicate the type of Reset that just occurred. This is
described in more detail in Section 5.7 “Reset State
of Registers”.
The RCON register also has a control bit for setting
interrupt priority (IPEN). Interrupt priority is discussed
in Section 11.0 “In terrupts”.
FIGURE 5-1: SIMPLI FI ED BLOCK DIAGRAM OF ON-CHIP RESET CIRCUIT
External Reset
MCLR
VDD
WDT
Time-out
VDD Rise
Detect
PWRT
LF-INTOSC
POR Pulse
Chip_Reset
Brown-out
Reset
RESET Instruction
Stack
Pointer
Stack Full/Underflow Reset
Sleep
( )_IDLE
32 sPWRT
11-Bit Ripple Counter
66 ms
S
RQ
Configuration Word Mismatch
PIC18F87K22 FAMILY
DS39960C-page 74 2011 Microchip Technology Inc.
REGISTER 5-1: RCON: RESET CONTROL REGISTER
R/W-0 R/W-1 R/W-1 R/W-1 R-1 R-1 R/W-0 R/W-0
IPEN SBOREN CM RI TO PD POR BOR
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 IPEN: Interrupt Priority Enable bit
1 = Enable priority levels on interrupts
0 = Disable priority levels on interrupts (PIC16CXXX Compatibility mode)
bit 6 SBOREN: BOR Software Enable bit
If BOREN<1:0> = 01:
1 = BOR is enabled
0 = BOR is disabled
If BOREN<1:0> = 00, 10 or 11:
Bit is disabled and read as ‘0’.
bit 5 CM: Configuration Mismatch Flag bit
1 = A Configuration Mismatch Reset has not occurred
0 = A Configuration Mismatch Reset has occurred (must be set in software after a Configuration
Mismatch Reset occurs)
bit 4 RI: RESET Instruction Flag bit
1 = The RESET instruction was not executed (set by firmware only)
0 = The RESET instruction was executed causing a device Reset (must be set in software after a
Brown-out Reset occurs)
bit 3 TO: Watchdog Time-out Flag bit
1 = Set by power-up, CLRWDT instruction or SLEEP instruction
0 = A WDT time-out occurred
bit 2 PD: Power-Down Detection Flag bit
1 = Set by power-up or by the CLRWDT instruction
0 = Set by execution of the SLEEP instruction
bit 1 POR: Power-on Reset Status bit
1 = A Power-on Reset has not occurred (set by firmware only)
0 = A Power-on Reset occurred (must be set in software after a Power-on Reset occurs)
bit 0 BOR: Brown-out Reset Status bit
1 = A Brown-out Reset has not occurred (set by firmware only)
0 = A Brown-out Reset occurred (must be set in software after a Brown-out Reset occurs)
Note 1: It is recommended that the POR bit be set after a Power-on Reset has been detected, so that subsequent
Power-on Resets may be detected.
2: Brown-out Reset is said to have occurred when BOR is ‘0’ and POR is ‘1’ (assuming that POR was set to
‘1’ by software immediately after a Power-on Reset).
2011 Microchip Technology Inc. DS39960C-page 75
PIC18F87K22 FAMILY
5.2 Master Clear (MCLR)
The MCLR pin provides a method for triggering a hard
external Reset of the device. A Reset is generated by
holding the pin low. PIC18 extended microcontroller
devices have a noise filter in the MCLR Reset path
which detects and ignores small pulses.
The MCLR pin is not driven low by any internal Resets,
including the WDT.
5.3 Power-on Reset (POR)
A Power-on Reset condition is generated on-chip
whenever VDD rises above a certain threshold. This
allows the device to start in the initialized state when
VDD is adequate for operation.
To take advantage of the POR circuitry, tie the MCLR
pin through a resistor (1 k to 10 k) to VDD. This will
eliminate external RC components usually needed to
create a Power-on Reset delay. A minimum rise rate for
VDD is specified (Parameter D004). For a slow rise
time, see Figure 5-2.
When the device starts normal operation (exiting the
Reset condition), device operating parameters (such
as voltage, frequency and temperature) must be met to
ensure operation. If these conditions are not met, the
device must be held in Reset until the operating
conditions are met.
Power-on Reset events are captured by the POR bit
(RCON<1>). The state of the bit is set to ‘0’ whenever
a Power-on Reset occurs and does not change for any
other Reset event. POR is not reset to ‘1’ by any
hardware event. To capture multiple events, the user
manually resets the bit to ‘1’ in software following any
Power-on Reset.
5.4 Brown-out Reset (BOR)
The PIC18F87K22 family has four BOR power modes:
• High-Power BOR
• Medium Power BOR
• Low-Power BOR
• Zero-Power BOR
Each power mode is selected by the BORPWR<1:0>
setting (CONFIG2L<6:5>). For low, medium and high-
power BOR, the module monitors the VDD depending
on the BORV<1:0> setting (CONFIG1L<3:2>). A BOR
event re-arms the Power-on Reset. It also causes a
Reset, depending on which of the trip levels has been
set: 1.8V, 2V, 2.7V or 3V.
BOR is enabled by BOREN<1:0> (CONFIG2L<2:1>)
and the SBOREN bit (RCON<6>). The typical current
draw (IBOR) for zero, low and medium power BOR is
200 nA, 750 nA and 3 A, respectively.
In Zero-Power BOR (ZPBORMV), the module monitors
the VDD voltage and re-arms the POR at about 2V.
ZPBORMV does not cause a Reset, but re-arms the
POR.
The BOR accuracy varies with its power level. The lower
the power setting, the less accurate the BOR trip levels
are. Therefore, the high-power BOR has the highest
accuracy and the low-power BOR has the lowest
accuracy. The trip levels (BVDD, Parameter D005), cur-
rent consumption (Section 31.2 “DC Characteristics:
Power-Down and Supply Current PIC18F87K22
Family (Industrial)”) and time required below BVDD
(TBOR, Parameter 35) can all be found in Section 31.0
“Electrical Characteristics”.
FIGURE 5-2: EXTERNAL POWER-ON
RESET CIRCUIT (FOR
SLOW VDD POWER-UP)
5.4.1 DETECTING BOR
The BOR bit always resets to ‘0’ on any Brown-out
Reset or Power-on Reset event. This makes it difficult
to determine if a Brown-out Reset event has occurred
just by reading the state of BOR alone. A more reliable
method is to simultaneously check the state of both
POR and BOR. This assumes that the POR bit is reset
to ‘1’ in software immediately after any Power-on Reset
event. If BOR is ‘0’ while POR is ‘1’, it can be reliably
assumed that a Brown-out Reset event has occurred.
LP-BOR cannot be detected with the BOR bit in the
RCON register. LP-BOR can rearm the POR and can
cause a Power-on Reset.
Note 1: External Power-on Reset circuit is required
only if the VDD power-up slope is too slow.
The diode, D, helps discharge the capacitor
quickly when VDD powers down.
2: R < 40 k is recommended to make sure that
the voltage drop across R does not violate
the device’s electrical specification.
3: R1 1 k will limit any current flowing into
MCLR from external capacitor, C, in the event
of MCLR/VPP pin breakdown, due to
Electrostatic Discharge (ESD) or Electrical
Overstress (EOS).
C
R1
R
D
VDD
MCLR
VDD
PIC18F87K22
PIC18F87K22 FAMILY
DS39960C-page 76 2011 Microchip Technology Inc.
5.5 Configuration Mismatch (CM)
The Configuration Mismatch (CM) Reset is designed to
detect, and attempt to recover from, random, memory
corrupting events. These include Electrostatic Discharge
(ESD) events that can cause widespread, single bit
changes throughout the device and result in catastrophic
failure.
In PIC18F87K22 family Flash devices, the device
Configuration registers (located in the configuration
memory space) are continuously monitored during
operation by comparing their values to complimentary
shadow registers. If a mismatch is detected between
the two sets of registers, a CM Reset automatically
occurs. These events are captured by the CM bit
(RCON<5>). The state of the bit is set to ‘0’ whenever
a CM event occurs and does not change for any other
Reset event.
A CM Reset behaves similarly to a Master Clear Reset,
RESET instruction, WDT time-out or Stack Event Reset.
As with all hard and power Reset events, the device
Configuration Words are reloaded from the Flash
Configuration Words in program memory as the device
restarts.
5.6 Power-up Timer (PWRT)
PIC18F87K22 family devices incorporate an on-chip
Power-up Timer (PWRT) to help regulate the Power-on
Reset process. The PWRT is enabled by setting the
PWRTEN bit (CONFIG2L<0>). The main function is to
ensure that the device voltage is stable before code is
executed.
The Power-up Timer (PWRT) of the PIC18F87K22
family devices is a 13-bit counter that uses the
LF-INTOSC source as the clock input. This yields an
approximate time interval of 2,048 x 32 s=66ms.
While the PWRT is counting, the device is held in
Reset.
The power-up time delay depends on the LF-INTOSC
clock and will vary from chip-to-chip due to temperature
and process variation. See DC Parameter 33 for
details.
5.6.1 TIME-OUT SEQUENCE
If enabled, the PWRT time-out is invoked after the POR
pulse has cleared. The total time-out will vary based on
the status of the PWRT. Figure 5-3, Figure 5-4,
Figure 5-5 and Figure 5-6 all depict time-out
sequences on power-up with the Power-up Timer
enabled.
Since the time-outs occur from the POR pulse, if
MCLR is kept low long enough, the PWRT will expire.
Bringing MCLR high will begin execution immediately
(Figure 5-5). This is useful for testing purposes, or for
synchronizing more than one PIC18 device operating
in parallel.
FIGURE 5-3: TIME-OUT SEQUENCE ON POWER-UP (MCLR TIED TO VDD, VDD RISE < TPWRT)
TPWRT
VDD
MCLR
INTERNAL POR
PWRT TIME-OUT
INTERNAL RESET
2011 Microchip Technology Inc. DS39960C-page 77
PIC18F87K22 FAMILY
FIGURE 5-4: TIME-OUT SEQUENCE ON POWER-UP (MCLR NOT TIED TO VDD): CASE 1
FIGURE 5-5: TIME-OUT SEQUENCE ON POWER-UP (MCLR NOT TIED TO VDD): CASE 2
FIGURE 5-6: SLOW RISE TIME (MCLR TIED TO VDD, V DD RISE > TPWRT)
TPWRT
VDD
MCLR
INTERNAL POR
PWRT TIME-OUT
INTERNAL RESET
VDD
MCLR
INTERNAL POR
PWRT TIME-OUT
INTERNAL RESET
TPWRT
VDD
MCLR
INTERNAL POR
PWRT TIME-OUT
INTERNAL RESET
0V 1V
3.3V
TPWRT
PIC18F87K22 FAMILY
DS39960C-page 78 2011 Microchip Technology Inc.
5.7 Reset State of Registers
Most registers are unaffected by a Reset. Their status
is unknown on POR and unchanged by all other
Resets. The other registers are forced to a “Reset
state” depending on the type of Reset that occurred.
Most registers are not affected by a WDT wake-up,
since this is viewed as the resumption of normal
operation. Status bits from the RCON register (CM, RI,
TO, PD, POR and BOR) are set or cleared differently in
different Reset situations, as indicated in Tab le 5 -1.
These bits are used in software to determine the nature
of the Reset.
Table 5-2 describes the Reset states for all of the
Special Function Registers. These are categorized by
Power-on and Brown-out Resets, Master Clear and
WDT Resets, and WDT wake-ups.
TABLE 5-1: STATUS BITS, THEIR SIGNIFICANCE AND THE INITIALIZATION CONDITION FOR
RCON REGISTER
Condition Program
Counter(1) RCON Register STKPTR Register
CM RI TO PD POR BOR STKFUL STKUNF
Power-on Reset 0000h 111100 0 0
RESET instruction 0000h u0uuuu u u
Brown-out Reset 0000h 1111u0 u u
Configuration Mismatch Reset 0000h 0uuuuu u u
MCLR Reset during
power-managed Run modes
0000h uu1uuu u u
MCLR Reset during power-
managed Idle modes and
Sleep mode
0000h uu10uu u u
MCLR Reset during full-power
execution
0000h uuuuuu u u
Stack Full Reset (STVREN = 1) 0000h uuuuuu 1 u
Stack Underflow Reset
(STVREN = 1)
0000h uuuuuu u 1
Stack Underflow Error (not an
actual Reset, STVREN = 0)
0000h uuuuuu u 1
WDT time-out during full-power
or power-managed Run modes
0000h uu0uuu u u
WDT time-out during
power-managed Idle or Sleep
modes
PC + 2 uu00uu u u
Interrupt exit from
power-managed modes
PC + 2 uuu0uu u u
Legend: u = unchanged
Note 1: When the wake-up is due to an interrupt and the GIEH or GIEL bit is set, the PC is loaded with the interrupt
vector (0008h or 0018h).
2011 Microchip Technology Inc. DS39960C-page 79
PIC18F87K22 FAMILY
TABLE 5-2: INITIALIZATION CONDITIONS FOR ALL REGISTERS
Register Applicable Devices Power-on Reset,
Brown-out Reset
MCLR Resets,
WDT Reset,
RESET Instruc tion,
Stack R esets,
CM Resets
Wake-up via WDT
or Interrupt
TOSU PIC18F6XK22 PIC18F8XK22 ---0 0000 ---0 0000 ---0 uuuu(1)
TOSH PIC18F6XK22 PIC18F8XK22 0000 0000 0000 0000 uuuu uuuu(1)
TOSL PIC18F6XK22 PIC18F8XK22 0000 0000 0000 0000 uuuu uuuu(1)
STKPTR PIC18F6XK22 PIC18F8XK22 00-0 0000 uu-0 0000 uu-u uuuu(1)
PCLATU PIC18F6XK22 PIC18F8XK22 ---0 0000 ---0 0000 ---u uuuu
PCLATH PIC18F6XK22 PIC18F8XK22 0000 0000 0000 0000 uuuu uuuu
PCL PIC18F6XK22 PIC18F8XK22 0000 0000 0000 0000 PC + 2(2)
TBLPTRU PIC18F6XK22 PIC18F8XK22 --00 0000 --00 0000 --uu uuuu
TBLPTRH PIC18F6XK22 PIC18F8XK22 0000 0000 0000 0000 uuuu uuuu
TBLPTRL PIC18F6XK22 PIC18F8XK22 0000 0000 0000 0000 uuuu uuuu
TABLAT PIC18F6XK22 PIC18F8XK22 0000 0000 0000 0000 uuuu uuuu
PRODH PIC18F6XK22 PIC18F8XK22 xxxx xxxx uuuu uuuu uuuu uuuu
PRODL PIC18F6XK22 PIC18F8XK22 xxxx xxxx uuuu uuuu uuuu uuuu
INTCON PIC18F6XK22 PIC18F8XK22 0000 000x 0000 000u uuuu uuuu(3)
INTCON2 PIC18F6XK22 PIC18F8XK22 1111 1111 1111 1111 uuuu uuuu(3)
INTCON3 PIC18F6XK22 PIC18F8XK22 1100 0000 1100 0000 uuuu uuuu(3)
INDF0 PIC18F6XK22 PIC18F8XK22 N/A N/A N/A
POSTINC0 PIC18F6XK22 PIC18F8XK22 N/A N/A N/A
POSTDEC0 PIC18F6XK22 PIC18F8XK22 N/A N/A N/A
PREINC0 PIC18F6XK22 PIC18F8XK22 N/A N/A N/A
PLUSW0 PIC18F6XK22 PIC18F8XK22 N/A N/A N/A
FSR0H PIC18F6XK22 PIC18F8XK22 ---- 0000 ---- 0000 ---- uuuu
FSR0L PIC18F6XK22 PIC18F8XK22 xxxx xxxx uuuu uuuu uuuu uuuu
WREG PIC18F6XK22 PIC18F8XK22 xxxx xxxx uuuu uuuu uuuu uuuu
INDF1 PIC18F6XK22 PIC18F8XK22 N/A N/A N/A
POSTINC1 PIC18F6XK22 PIC18F8XK22 N/A N/A N/A
POSTDEC1 PIC18F6XK22 PIC18F8XK22 N/A N/A N/A
PREINC1 PIC18F6XK22 PIC18F8XK22 N/A N/A N/A
PLUSW1 PIC18F6XK22 PIC18F8XK22 N/A N/A N/A
FSR1H PIC18F6XK22 PIC18F8XK22 ---- 0000 ---- 0000 ---- uuuu
FSR1L PIC18F6XK22 PIC18F8XK22 xxxx xxxx uuuu uuuu uuuu uuuu
BSR PIC18F6XK22 PIC18F8XK22 ---- 0000 ---- 0000 ---- uuuu
Legend: u = unchanged, x = unknown, - = unimplemented bit, read as ‘0’, q = value depends on condition.
Shaded cells indicate conditions do not apply for the designated device.
Note 1: When the wake-up is due to an interrupt and the GIEL or GIEH bit is set, the TOSU, TOSH and TOSL are
updated with the current value of the PC. The STKPTR is modified to point to the next location in the hardware
stack.
2: When the wake-up is due to an interrupt and the GIEL or GIEH bit is set, the PC is loaded with the interrupt vector
(0008h or 0018h).
3: One or more bits in the INTCONx or PIRx registers will be affected (to cause wake-up).
4: See Table 5-1 for Reset value for specific condition.
PIC18F87K22 FAMILY
DS39960C-page 80 2011 Microchip Technology Inc.
INDF2 PIC18F6XK22 PIC18F8XK22 N/A N/A N/A
POSTINC2 PIC18F6XK22 PIC18F8XK22 N/A N/A N/A
POSTDEC2 PIC18F6XK22 PIC18F8XK22 N/A N/A N/A
PREINC2 PIC18F6XK22 PIC18F8XK22 N/A N/A N/A
PLUSW2 PIC18F6XK22 PIC18F8XK22 N/A N/A N/A
FSR2H PIC18F6XK22 PIC18F8XK22 ---- xxxx ----uuuu ---- uuuu
FSR2L PIC18F6XK22 PIC18F8XK22 xxxx xxxx uuuu uuuu uuuu uuuu
STATUS PIC18F6XK22 PIC18F8XK22 ---x xxxx ---u uuuu ---u uuuu
TMR0H PIC18F6XK22 PIC18F8XK22 0000 0000 uuuu uuuu uuuu uuuu
TMR0L PIC18F6XK22 PIC18F8XK22 xxxx xxxx uuuu uuuu uuuu uuuu
T0CON PIC18F6XK22 PIC18F8XK22 1111 1111 1111 1111 uuuu uuuu
SPBRGH1 PIC18F6XK22 PIC18F8XK22 0000 0000 0000 0000 uuuu uuuu
OSCCON PIC18F6XK22 PIC18F8XK22 0110 q000 0110 q000 uuuu quuu
IPR5 PIC18F65K22 PIC18F85K22 ---1 -111 ---1 -111 ---u -uuu
IPR5 PIC18F66K22
PIC18F67K22
PIC18F86K22
PIC18F87K22 1000 0000 1000 0000 uuuu uuuu
WDTCON PIC18F6XK22 PIC18F8XK22 0-x0 -000 0-x0 -000 u-uu -uuu
RCON PIC18F6XK22 PIC18F8XK22 0111 11qq 0uqq qquu uuuu qquu
TMR1H PIC18F6XK22 PIC18F8XK22 xxxx xxxx uuuu uuuu uuuu uuuu
TMR1L PIC18F6XK22 PIC18F8XK22 xxxx xxxx uuuu uuuu uuuu uuuu
T1CON PIC18F6XK22 PIC18F8XK22 0000 0000 uuuu uuuu uuuu uuuu
TMR2 PIC18F6XK22 PIC18F8XK22 0000 0000 0000 0000 uuuu uuuu
PR2 PIC18F6XK22 PIC18F8XK22 1111 1111 1111 1111 uuuu uuuu
T2CON PIC18F6XK22 PIC18F8XK22 -000 0000 -000 0000 -uuu uuuu
SSP1BUF PIC18F6XK22 PIC18F8XK22 xxxx xxxx uuuu uuuu uuuu uuuu
SSP1ADD PIC18F6XK22 PIC18F8XK22 0000 0000 0000 0000 uuuu uuuu
SSP1STAT PIC18F6XK22 PIC18F8XK22 0000 0000 0000 0000 uuuu uuuu
SSP1CON1 PIC18F6XK22 PIC18F8XK22 0000 0000 0000 0000 uuuu uuuu
SSP1CON2 PIC18F6XK22 PIC18F8XK22 0000 0000 0000 0000 uuuu uuuu
ADRESH PIC18F6XK22 PIC18F8XK22 xxxx xxxx uuuu uuuu uuuu uuuu
ADRESL PIC18F6XK22 PIC18F8XK22 xxxx xxxx uuuu uuuu uuuu uuuu
ADCON0 PIC18F6XK22 PIC18F8XK22 -000 0000 -000 0000 -uuu uuuu
ADCON1 PIC18F6XK22 PIC18F8XK22 0000 0000 0000 0000 uuuu uuuu
ADCON2 PIC18F6XK22 PIC18F8XK22 0-00 0000 0-00 0000 u-uu uuuu
TABLE 5-2: INITIALIZATION CONDITIONS FOR ALL REGISTERS (CONTINUED)
Register Applicable Devices Power-on Reset,
Brown-out Reset
MCLR Resets,
WDT Reset,
RESET Instruc tion,
Stack R esets,
CM Resets
Wake-up via WDT
or Interrupt
Legend: u = unchanged, x = unknown, - = unimplemented bit, read as ‘0’, q = value depends on condition.
Shaded cells indicate conditions do not apply for the designated device.
Note 1: When the wake-up is due to an interrupt and the GIEL or GIEH bit is set, the TOSU, TOSH and TOSL are
updated with the current value of the PC. The STKPTR is modified to point to the next location in the hardware
stack.
2: When the wake-up is due to an interrupt and the GIEL or GIEH bit is set, the PC is loaded with the interrupt vector
(0008h or 0018h).
3: One or more bits in the INTCONx or PIRx registers will be affected (to cause wake-up).
4: See Table 5-1 for Reset value for specific condition.
2011 Microchip Technology Inc. DS39960C-page 81
PIC18F87K22 FAMILY
ECCP1AS PIC18F6XK22 PIC18F8XK22 0000 0000 0000 0000 uuuu uuuu
ECCP1DEL PIC18F6XK22 PIC18F8XK22 0000 0000 0000 0000 uuuu uuuu
CCPR1H PIC18F6XK22 PIC18F8XK22 xxxx xxxx uuuu uuuu uuuu uuuu
CCPR1L PIC18F6XK22 PIC18F8XK22 xxxx xxxx uuuu uuuu uuuu uuuu
CCP1CON PIC18F6XK22 PIC18F8XK22 0000 0000 0000 0000 uuuu uuuu
PIR5 PIC18F65K22 PIC18F85K22 ---0 -000 ---0 -000 ---u -uuu
PIR5 PIC18F66K22
PIC18F67K22
PIC18F86K22
PIC18F87K22 0000 0000 0000 0000 uuuu uuuu
PIE5 PIC18F65K22 PIC18F85K22 ---0 0000 ---0 0000 ---u uuuu(1)
PIE5 PIC18F66K22
PIC18F67K22
PIC18F86K22
PIC18F87K22 0000 000 0000 0000 uuuu uuuu(1)
IPR4 PIC18F65K22 PIC18F85K22 --11 1111 --11 1111 --uu uuuu
IPR4 PIC18F66K22
PIC18F67K22
PIC18F86K22
PIC18F87K22 1111 1111 1111 1111 uuuu uuuu
PIR4 PIC18F65K22 PIC18F85K22 --00 0000 --00 0000 --uu uuuu(1)
PIR4 PIC18F66K22
PIC18F67K22
PIC18F86K22
PIC18F87K22 0000 0000 0000 0000 uuuu uuuu(1)
PIE4 PIC18F65K22 PIC18F85K22 --00 0000 --00 0000 --uu uuuu
PIE4 PIC18F66K22
PIC18F67K22
PIC18F86K22
PIC18F87K22 0000 0000 0000 0000 uuuu uuuu
CVRCON PIC18F6XK22 PIC18F8XK22 0000 0000 0000 0000 uuuu uuuu
CMSTAT PIC18F6XK22 PIC18F8XK22 xxx- ---- xxx- ---- uuu- ----
TMR3H PIC18F6XK22 PIC18F8XK22 xxxx xxxx uuuu uuuu uuuu uuuu
TMR3L PIC18F6XK22 PIC18F8XK22 xxxx xxxx uuuu uuuu uuuu uuuu
T3CON PIC18F6XK22 PIC18F8XK22 0000 0000 0000 0x00 uuuu uuuu
T3GCON PIC18F6XK22 PIC18F8XK22 0000 0x00 0000 0000 uuuu uuuu
SPBRG1 PIC18F6XK22 PIC18F8XK22 0000 0000 0000 0000 uuuu uuuu
RCREG1 PIC18F6XK22 PIC18F8XK22 0000 0000 0000 0000 uuuu uuuu
TXREG1 PIC18F6XK22 PIC18F8XK22 xxxx xxxx xxxx xxxx uuuu uuuu
TXSTA1 PIC18F6XK22 PIC18F8XK22 0000 0010 0000 0010 uuuu uuuu
RCSTA1 PIC18F6XK22 PIC18F8XK22 0000 000x 0000 000x uuuu uuuu
T1GCON PIC18F6XK22 PIC18F8XK22 0000 0x00 0000 0x00 uuuu -uuu
IPR6 PIC18F6XK22 PIC18F8XK22 ---1 -111 ---1 -111 ---u -uuu
HLVDCON PIC18F6XK22 PIC18F8XK22 0000 0101 0000 0101 uuuu uuuu
PSPCON PIC18F6XK22 PIC18F8XK22 0000 ---- 0000 ---- uuuu ----
PIR6 PIC18F6XK22 PIC18F8XK22 ---0 -000 ---0 -000 ---u -uuu
TABLE 5-2: INITIALIZATION CONDITIONS FOR ALL REGISTERS (CONTINUED)
Register Applicable Devices Power-on Reset,
Brown-out Reset
MCLR Resets,
WDT Reset,
RESET Instruc tion,
Stack R esets,
CM Resets
Wake-up via WDT
or Interrupt
Legend: u = unchanged, x = unknown, - = unimplemented bit, read as ‘0’, q = value depends on condition.
Shaded cells indicate conditions do not apply for the designated device.
Note 1: When the wake-up is due to an interrupt and the GIEL or GIEH bit is set, the TOSU, TOSH and TOSL are
updated with the current value of the PC. The STKPTR is modified to point to the next location in the hardware
stack.
2: When the wake-up is due to an interrupt and the GIEL or GIEH bit is set, the PC is loaded with the interrupt vector
(0008h or 0018h).
3: One or more bits in the INTCONx or PIRx registers will be affected (to cause wake-up).
4: See Table 5-1 for Reset value for specific condition.
PIC18F87K22 FAMILY
DS39960C-page 82 2011 Microchip Technology Inc.
IPR3 PIC18F6XK22 PIC18F8XK22 1-11 1111 1-11 1111 u-uu uuuu
PIR3 PIC18F6XK22 PIC18F8XK22 0-00 0000 0-00 0000 u-uu uuuu
PIE3 PIC18F6XK22 PIC18F8XK22 0-00 0000 0-00 0000 u-uu uuuu
IPR2 PIC18F6XK22 PIC18F8XK22 1-11 1111 1-11 1111 u-uu uuuu
PIR2 PIC18F6XK22 PIC18F8XK22 0-10 0000 0-10 0000 u-uu uuuu
PIE2 PIC18F6XK22 PIC18F8XK22 0-00 0000 0-00 0000 u-uu uuuu
IPR1 PIC18F6XK22 PIC18F8XK22 1111 1111 1111 1111 uuuu uuuu
PIR1 PIC18F6XK22 PIC18F8XK22 0000 0000 0000 0000 uuuu uuuu
PIE1 PIC18F6XK22 PIC18F8XK22 0000 0000 0000 0000 uuuu uuuu
PSTR1CON PIC18F6XK22 PIC18F8XK22 00-0 0001 00-0 0001 uu-u uuuu
OSCTUNE PIC18F6XK22 PIC18F8XK22 0000 0000 0000 0000 uuuu uuuu
TRISJ PIC18F6XK22 PIC18F8XK22 1111 1111 1111 1111 uuuu uuuu
TRISH PIC18F6XK22 PIC18F8XK22 1111 1111 1111 1111 uuuu uuuu
TRISG PIC18F6XK22 PIC18F8XK22 ---1 1111 ---1 1111 ---u uuuu
TRISF PIC18F6XK22 PIC18F8XK22 1111 111- 1111 111- ---u uuuu
TRISE PIC18F6XK22 PIC18F8XK22 1111 1111 1111 1111 uuuu uuuu
TRISD PIC18F6XK22 PIC18F8XK22 1111 1111 1111 1111 uuuu uuuu
TRISC PIC18F6XK22 PIC18F8XK22 1111 1111 1111 1111 uuuu uuuu
TRISB PIC18F6XK22 PIC18F8XK22 1111 1111 1111 1111 uuuu uuuu
TRISA PIC18F6XK22 PIC18F8XK22 1111 1111 1111 1111 uuuu uuuu
LATJ PIC18F6XK22 PIC18F8XK22 xxxx xxxx uuuu uuuu uuuu uuuu
LATH PIC18F6XK22 PIC18F8XK22 xxxx xxxx uuuu uuuu uuuu uuuu
LATG PIC18F6XK22 PIC18F8XK22 ---x xxxx ---u uuuu ---u uuuu
LATF PIC18F6XK22 PIC18F8XK22 xxxx xxx- uuuu uuu- uuuu uuu-
LATE PIC18F6XK22 PIC18F8XK22 xxxx xxxx uuuu uuuu uuuu uuuu
LATD PIC18F6XK22 PIC18F8XK22 xxxx xxxx uuuu uuuu uuuu uuuu
LATC PIC18F6XK22 PIC18F8XK22 xxxx xxxx uuuu uuuu uuuu uuuu
LATB PIC18F6XK22 PIC18F8XK22 xxxx xxxx uuuu uuuu uuuu uuuu
LATA PIC18F6XK22 PIC18F8XK22 xxxx xxxx uuuu uuuu uuuu uuuu
PORTJ PIC18F6XK22 PIC18F8XK22 xxxx xxxx xxxx xxxx uuuu uuuu
PORTH PIC18F6XK22 PIC18F8XK22 xxxx xxxx xxxx xxxx uuuu uuuu
PORTG PIC18F6XK22 PIC18F8XK22 --xx xxxx --xx xxxx --uu uuuu
PORTF PIC18F6XK22 PIC18F8XK22 xxxx xxx- xxxx xxx- uuuu uuu-
PORTE PIC18F6XK22 PIC18F8XK22 xxxx xxxx xxxx xxxx uuuu uuuu
PORTD PIC18F6XK22 PIC18F8XK22 xxxx xxxx xxxx xxxx uuuu uuuu
TABLE 5-2: INITIALIZATION CONDITIONS FOR ALL REGISTERS (CONTINUED)
Register Applicable Devices Power-on Reset,
Brown-out Reset
MCLR Resets,
WDT Reset,
RESET Instruc tion,
Stack R esets,
CM Resets
Wake-up via WDT
or Interrupt
Legend: u = unchanged, x = unknown, - = unimplemented bit, read as ‘0’, q = value depends on condition.
Shaded cells indicate conditions do not apply for the designated device.
Note 1: When the wake-up is due to an interrupt and the GIEL or GIEH bit is set, the TOSU, TOSH and TOSL are
updated with the current value of the PC. The STKPTR is modified to point to the next location in the hardware
stack.
2: When the wake-up is due to an interrupt and the GIEL or GIEH bit is set, the PC is loaded with the interrupt vector
(0008h or 0018h).
3: One or more bits in the INTCONx or PIRx registers will be affected (to cause wake-up).
4: See Table 5-1 for Reset value for specific condition.
2011 Microchip Technology Inc. DS39960C-page 83
PIC18F87K22 FAMILY
PORTC PIC18F6XK22 PIC18F8XK22 xxxx xxxx uuuu uuuu uuuu uuuu
PORTB PIC18F6XK22 PIC18F8XK22 xxxx xxxx uuuu uuuu uuuu uuuu
PORTA PIC18F6XK22 PIC18F8XK22 xx0x 0000 uu0u 0000 uuuu uuuu
EECON1 PIC18F6XK22 PIC18F8XK22 xx-0 x000 uu-0 u000 uu-u uuuu
EECON2 PIC18F6XK22 PIC18F8XK22 ---- ---- ---- ---- ---- ----
TMR5H PIC18F6XK22 PIC18F8XK22 xxxx xxxx uuuu uuuu uuuu uuuu
TMR5L PIC18F6XK22 PIC18F8XK22 xxxx xxxx uuuu uuuu uuuu uuuu
T5CON PIC18F6XK22 PIC18F8XK22 0000 0000 uuuu uuuu uuuu uuuu
T5GCON PIC18F6XK22 PIC18F8XK22 0000 0x00 uuuu uuuu uuuu uuuu
CCPR4H PIC18F6XK22 PIC18F8XK22 xxxx xxxx uuuu uuuu uuuu uuuu
CCPR4L PIC18F6XK22 PIC18F8XK22 xxxx xxxx uuuu uuuu uuuu uuuu
CCP4CON PIC18F6XK22 PIC18F8XK22 --00 0000 --00 0000 --uu uuuu
CCPR5H PIC18F6XK22 PIC18F8XK22 xxxx xxxx uuuu uuuu uuuu uuuu
CCPR5L PIC18F6XK22 PIC18F8XK22 xxxx xxxx uuuu uuuu uuuu uuuu
CCP5CON PIC18F6XK22 PIC18F8XK22 --00 0000 --00 0000 --uu uuuu
CCPR6H PIC18F6XK22 PIC18F8XK22 xxxx xxxx uuuu uuuu uuuu uuuu
CCPR6L PIC18F6XK22 PIC18F8XK22 xxxx xxxx uuuu uuuu uuuu uuuu
CCP6CON PIC18F6XK22 PIC18F8XK22 --00 0000 --00 0000 --uu uuuu
CCPR7H PIC18F6XK22 PIC18F8XK22 xxxx xxxx uuuu uuuu uuuu uuuu
CCPR7L PIC18F6XK22 PIC18F8XK22 xxxx xxxx uuuu uuuu uuuu uuuu
CCP7CON PIC18F6XK22 PIC18F8XK22 --00 0000 --00 0000 --uu uuuu
TMR4 PIC18F6XK22 PIC18F8XK22 xxxx xxxx xxxx xxxx uuuu uuuu
PR4 PIC18F6XK22 PIC18F8XK22 1111 1111 1111 1111 1111 1111
T4CON PIC18F6XK22 PIC18F8XK22 -111 1111 -111 1111 -uuu uuuu
SSP2BUF PIC18F6XK22 PIC18F8XK22 xxxx xxxx uuuu uuuu uuuu uuuu
SSP2ADD PIC18F6XK22 PIC18F8XK22 0000 0000 0000 0000 uuuu uuuu
SSP2STAT PIC18F6XK22 PIC18F8XK22 0000 0000 0000 0000 uuuu uuuu
SSP2CON1 PIC18F6XK22 PIC18F8XK22 0000 0000 0000 0000 uuuu uuuu
SSP2CON2 PIC18F6XK22 PIC18F8XK22 0100 0000 0000 0000 uuuu uuuu
BAUDCON1 PIC18F6XK22 PIC18F8XK22 0100 0-00 0100 0-00 uuuu u-uu
OSCCON2 PIC18F6XK22 PIC18F8XK22 -0-- 0-x0 -0-- 0-u0 -u-- u-uu
EEADRH PIC18F6XK22 PIC18F8XK22 ---- --00 ---- --00 ---- --uu
EEADR PIC18F6XK22 PIC18F8XK22 0000 0000 0000 0000 uuuu uuuu
EEDATA PIC18F6XK22 PIC18F8XK22 0000 0000 0000 0000 uuuu uuuu
PIE6 PIC18F6XK22 PIC18F8XK22 ---0 -000 ---0 -000 ---u -uuu
TABLE 5-2: INITIALIZATION CONDITIONS FOR ALL REGISTERS (CONTINUED)
Register Applicable Devices Power-on Reset,
Brown-out Reset
MCLR Resets,
WDT Reset,
RESET Instruc tion,
Stack R esets,
CM Resets
Wake-up via WDT
or Interrupt
Legend: u = unchanged, x = unknown, - = unimplemented bit, read as ‘0’, q = value depends on condition.
Shaded cells indicate conditions do not apply for the designated device.
Note 1: When the wake-up is due to an interrupt and the GIEL or GIEH bit is set, the TOSU, TOSH and TOSL are
updated with the current value of the PC. The STKPTR is modified to point to the next location in the hardware
stack.
2: When the wake-up is due to an interrupt and the GIEL or GIEH bit is set, the PC is loaded with the interrupt vector
(0008h or 0018h).
3: One or more bits in the INTCONx or PIRx registers will be affected (to cause wake-up).
4: See Table 5-1 for Reset value for specific condition.
PIC18F87K22 FAMILY
DS39960C-page 84 2011 Microchip Technology Inc.
RTCCFG PIC18F6XK22 PIC18F8XK22 0-00 0000 u-uu uuuu u-uu uuuu
RTCCAL PIC18F6XK22 PIC18F8XK22 0000 0000 uuuu uuuu uuuu uuuu
RTCVALH PIC18F6XK22 PIC18F8XK22 xxxx xxxx uuuu uuuu uuuu uuuu
RTCVALL PIC18F6XK22 PIC18F8XK22 0000 0000 uuuu uuuu uuuu uuuu
ALRMCFG PIC18F6XK22 PIC18F8XK22 0000 0000 uuuu uuuu uuuu uuuu
ALRMRPT PIC18F6XK22 PIC18F8XK22 0000 0000 uuuu uuuu uuuu uuuu
ALRMVALH PIC18F6XK22 PIC18F8XK22 xxxx xxxx uuuu uuuu uuuu uuuu
ALRMVALL PIC18F6XK22 PIC18F8XK22 xxxx xxxx uuuu uuuu uuuu uuuu
CTMUCONH PIC18F6XK22 PIC18F8XK22 0-00 0000 0-00 0000 u-uu uuuu
CTMUCONL PIC18F6XK22 PIC18F8XK22 0000 00xx 0000 00xx uuuu uuuu
CTMUICONH PIC18F6XK22 PIC18F8XK22 0000 0000 0000 0000 uuuu uuuu
CM1CON PIC18F6XK22 PIC18F8XK22 0001 1111 0001 1111 uuuu uuuu
PADCFG1 PIC18F6XK22 PIC18F8XK22 00-- -00- uu-- -uu- uu-- -uu-
PADCFG1 PIC18F6XK22 PIC18F8XK22 000- -00- uuu- -uu- uuu- -uu-
ECCP2AS PIC18F6XK22 PIC18F8XK22 0000 0000 0000 0000 uuuu uuuu
ECCP2DEL PIC18F6XK22 PIC18F8XK22 0000 0000 0000 0000 uuuu uuuu
CCPR2H PIC18F6XK22 PIC18F8XK22 xxxx xxxx uuuu uuuu uuuu uuuu
CCPR2L PIC18F6XK22 PIC18F8XK22 xxxx xxxx uuuu uuuu uuuu uuuu
CCP2CON PIC18F6XK22 PIC18F8XK22 0000 0000 0000 0000 uuuu uuuu
ECCP3AS PIC18F6XK22 PIC18F8XK22 0000 0000 0000 0000 uuuu uuuu
ECCP3DEL PIC18F6XK22 PIC18F8XK22 0000 0000 0000 0000 uuuu uuuu
CCPR3H PIC18F6XK22 PIC18F8XK22 xxxx xxxx uuuu uuuu uuuu uuuu
CCPR3L PIC18F6XK22 PIC18F8XK22 xxxx xxxx uuuu uuuu uuuu uuuu
CCP3CON PIC18F6XK22 PIC18F8XK22 0000 0000 0000 0000 uuuu uuuu
CCPR8H PIC18F6XK22 PIC18F8XK22 xxxx xxxx uuuu uuuu uuuu uuuu
CCPR8L PIC18F6XK22 PIC18F8XK22 xxxx xxxx uuuu uuuu uuuu uuuu
CCP8CON PIC18F6XK22 PIC18F8XK22 --00 0000 --00 0000 --uu uuuu
CCPR9H PIC18F66K22
PIC18F67K22
PIC18F86K22
PIC18F87K22 xxxx xxxx uuuu uuuu uuuu uuuu
CCPR9L PIC18F66K22
PIC18F67K22
PIC18F86K22
PIC18F87K22 xxxx xxxx uuuu uuuu uuuu uuuu
CCP9CON PIC18F66K22
PIC18F67K22
PIC18F86K22
PIC18F87K22 --00 0000 --00 0000 --uu uuuu
CCPR10H PIC18F66K22
PIC18F67K22
PIC18F86K22
PIC18F87K22 xxxx xxxx uuuu uuuu uuuu uuuu
CCPR10L PIC18F66K22
PIC18F67K22
PIC18F86K22
PIC18F87K22 xxxx xxxx uuuu uuuu uuuu uuuu
TABLE 5-2: INITIALIZATION CONDITIONS FOR ALL REGISTERS (CONTINUED)
Register Applicable Devices Power-on Reset,
Brown-out Reset
MCLR Resets,
WDT Reset,
RESET Instruc tion,
Stack R esets,
CM Resets
Wake-up via WDT
or Interrupt
Legend: u = unchanged, x = unknown, - = unimplemented bit, read as ‘0’, q = value depends on condition.
Shaded cells indicate conditions do not apply for the designated device.
Note 1: When the wake-up is due to an interrupt and the GIEL or GIEH bit is set, the TOSU, TOSH and TOSL are
updated with the current value of the PC. The STKPTR is modified to point to the next location in the hardware
stack.
2: When the wake-up is due to an interrupt and the GIEL or GIEH bit is set, the PC is loaded with the interrupt vector
(0008h or 0018h).
3: One or more bits in the INTCONx or PIRx registers will be affected (to cause wake-up).
4: See Table 5-1 for Reset value for specific condition.
2011 Microchip Technology Inc. DS39960C-page 85
PIC18F87K22 FAMILY
CCP10CON PIC18F66K22
PIC18F67K22
PIC18F86K22
PIC18F87K22 --00 0000 --00 0000 --uu uuuu
TMR7H PIC18F66K22
PIC18F67K22
PIC18F86K22
PIC18F87K22 xxxx xxxx uuuu uuuu uuuu uuuu
TMR7L PIC18F66K22
PIC18F67K22
PIC18F86K22
PIC18F87K22 xxxx xxxx uuuu uuuu uuuu uuuu
T7CON PIC18F66K22
PIC18F67K22
PIC18F86K22
PIC18F87K22 0000 0000 uuuu uuuu uuuu uuuu
T7GCON PIC18F66K22
PIC18F67K22
PIC18F86K22
PIC18F87K22 0000 0x00 0000 0x00 uuuu uuuu
TMR6 PIC18F6XK22 PIC18F8XK22 0000 0000 0000 0000 uuuu uuuu
PR6 PIC18F6XK22 PIC18F8XK22 1111 1111 1111 1111 uuuu uuuu
T6CON PIC18F6XK22 PIC18F8XK22 -000 0000 -000 0000 -uuu uuuu
TMR8 PIC18F6XK22 PIC18F8XK22 0000 0000 0000 0000 uuuu uuuu
PR8 PIC18F6XK22 PIC18F8XK22 1111 1111 1111 1111 uuuu uuuu
T8CON PIC18F6XK22 PIC18F8XK22 -000 0000 -000 0000 -uuu uuuu
TMR10 PIC18F66K22
PIC18F67K22
PIC18F86K22
PIC18F87K22 0000 0000 0000 0000 uuuu uuuu
PR10 PIC18F66K22
PIC18F67K22
PIC18F86K22
PIC18F87K22 1111 1111 1111 1111 uuuu uuuu
T10CON PIC18F66K22
PIC18F67K22
PIC18F86K22
PIC18F87K22 -000 0000 -000 0000 -uuu uuuu
TMR12 PIC18F66K22
PIC18F67K22
PIC18F86K22
PIC18F87K22 0000 0000 0000 0000 uuuu uuuu
PR12 PIC18F66K22
PIC18F67K22
PIC18F86K22
PIC18F87K22 1111 1111 1111 1111 uuuu uuuu
T12CON PIC18F66K22
PIC18F67K22
PIC18F86K22
PIC18F87K22 -000 0000 -000 0000 -uuu uuuu
CM2CON PIC18F6XK22 PIC18F8XK22 0001 1111 0001 1111 uuuu uuuu
CM3CON PIC18F6XK22 PIC18F8XK22 0001 1111 0001 1111 uuuu uuuu
CCPTMRS0 PIC18F6XK22 PIC18F8XK22 0000 0000 uuuu uuuu uuuu uuuu
CCPTMRS1 PIC18F6XK22 PIC18F8XK22 00-0 -000 uu-u -uuu uu-u -uuu
CCPTMRS2 PIC18F66K22
PIC18F67K22
PIC18F86K22
PIC18F87K22 ---0 -000 ---u -uuu ---u -uuu
CCPTMRS2 PIC18F65K22 PIC18F85K22 ---- --00 ---- --uu ---- --uu
REFOCON PIC18F6XK22 PIC18F8XK22 0-00 0000 u-uu uuuu u-uu uuuu
ODCON1 PIC18F6XK22 PIC18F8XK22 000- ---0 uuu- ---u uuu- ---u
TABLE 5-2: INITIALIZATION CONDITIONS FOR ALL REGISTERS (CONTINUED)
Register Applicable Devices Power-on Reset,
Brown-out Reset
MCLR Resets,
WDT Reset,
RESET Instruc tion,
Stack R esets,
CM Resets
Wake-up via WDT
or Interrupt
Legend: u = unchanged, x = unknown, - = unimplemented bit, read as ‘0’, q = value depends on condition.
Shaded cells indicate conditions do not apply for the designated device.
Note 1: When the wake-up is due to an interrupt and the GIEL or GIEH bit is set, the TOSU, TOSH and TOSL are
updated with the current value of the PC. The STKPTR is modified to point to the next location in the hardware
stack.
2: When the wake-up is due to an interrupt and the GIEL or GIEH bit is set, the PC is loaded with the interrupt vector
(0008h or 0018h).
3: One or more bits in the INTCONx or PIRx registers will be affected (to cause wake-up).
4: See Table 5-1 for Reset value for specific condition.
PIC18F87K22 FAMILY
DS39960C-page 86 2011 Microchip Technology Inc.
ODCON2 PIC18F66K22
PIC18F67K22
PIC18F86K22
PIC18F87K22 0000 0000 uuuu uuuu uuuu uuuu
ODCON2 PIC18F65K22 PIC18F85K22 --00 0000 --uu uuuu --uu uuuu
ODCON3 PIC18F6XK22 PIC18F8XK22 00-- ---0 uu-- ---u uu-- ---u
MEMCON PIC18F6XK22 PIC18F8XK22 0-00 --00 0-00 --00 u-uu --uu
ANCON0 PIC18F6XK22 PIC18F8XK22 1111 1111 uuuu uuuu uuuu uuuu
ANCON1 PIC18F6XK22 PIC18F8XK22 1111 1111 uuuu uuuu uuuu uuuu
ANCON2 PIC18F6XK22 PIC18F8XK22 1111 1111 uuuu uuuu uuuu uuuu
RCSTA2 PIC18F6XK22 PIC18F8XK22 0000 000x 0000 000x uuuu uuuu
TXSTA2 PIC18F6XK22 PIC18F8XK22 0000 0010 0000 0010 uuuu uuuu
BAUDCON2 PIC18F6XK22 PIC18F8XK22 0100 0-00 0100 0-00 uuuu u-uu
SPBRGH2 PIC18F6XK22 PIC18F8XK22 0000 0000 0000 0000 uuuu uuuu
SPBRG2 PIC18F6XK22 PIC18F8XK22 0000 0000 0000 0000 uuuu uuuu
RCREG2 PIC18F6XK22 PIC18F8XK22 0000 0000 0000 0000 uuuu uuuu
TXREG2 PIC18F6XK22 PIC18F8XK22 x xx x xx xx xxxx xxx x uuuu uuuu
PSTR2CON PIC18F6XK22 PIC18F8XK22 00-0 0001 00-0 0001 uu-u uuuu
PSTR3CON PIC18F6XK22 PIC18F8XK22 00-0 0001 00-0 0001 uu-u uuuu
PMD0 PIC18F6XK22 PIC18F8XK22 0000 0000 0000 0000 uuuu uuuu
PMD1 PIC18F6XK22 PIC18F8XK22 0000 0000 0000 0000 uuuu uuuu
PMD2 PIC18F66K22
PIC18F67K22
PIC18F86K22
PIC18F87K22 0000 0000 0000 0000 uuuu uuuu
PMD2 PIC18F65K22 PIC18F85K22 -0-0 0000 -0-0 0000 -u-u uuuu
PMD3 PIC18F66K22
PIC18F67K22
PIC18F86K22
PIC18F87K22 0000 0000 0000 0000 uuuu uuuu
PMD3 PIC18F65K22 PIC18F85K22 --00 000- --00 000- --uu uuu-
TABLE 5-2: INITIALIZATION CONDITIONS FOR ALL REGISTERS (CONTINUED)
Register Applicable Devices Power-on Reset,
Brown-out Reset
MCLR Resets,
WDT Reset,
RESET Instruc tion,
Stack R esets,
CM Resets
Wake-up via WDT
or Interrupt
Legend: u = unchanged, x = unknown, - = unimplemented bit, read as ‘0’, q = value depends on condition.
Shaded cells indicate conditions do not apply for the designated device.
Note 1: When the wake-up is due to an interrupt and the GIEL or GIEH bit is set, the TOSU, TOSH and TOSL are
updated with the current value of the PC. The STKPTR is modified to point to the next location in the hardware
stack.
2: When the wake-up is due to an interrupt and the GIEL or GIEH bit is set, the PC is loaded with the interrupt vector
(0008h or 0018h).
3: One or more bits in the INTCONx or PIRx registers will be affected (to cause wake-up).
4: See Table 5-1 for Reset value for specific condition.
2011 Microchip Technology Inc. DS39960C-page 87
PIC18F87K22 FAMILY
6.0 MEMORY ORGANIZATION
PIC18F87K22 family devices have these types of
memory:
• Program Memory
• Data RAM
• Data EEPROM
As Harvard architecture devices, the data and program
memories use separate busses. This enables
concurrent access of the two memory spaces.
The data EEPROM, for practical purposes, can be
regarded as a peripheral device because it is
addressed and accessed through a set of control
registers.
Additional detailed information on the operation of the
Flash program memory is provided in Section 7.0
“Flash Program Memory”. The data EEPROM is
discussed separately in Section 9.0 “Data EEPROM
Memory”.
FIGURE 6-1: MEMORY MAPS FOR PIC18F87K22 FAMILY DEVICES
Note: Sizes of memory areas are not to scale. Sizes of program memory areas are enhanced to show detail.
Unimplemented
Read as ‘0’
Unimplemented
Read as ‘0’
000000h
1FFFFFh
01FFFFh
00FFFFh
PC<20:0>
Stack Level 1
Stack Level 31
CALL, CALLW, RCALL,
RETURN, RETFIE, RETLW,
21
User Memory Space
On-Chip
Memory
On-Chip
Memory
ADDULNK, SUBULNK
PIC18FX6K22 PIC18FX7K22
Unimplemented
Read as ‘0’
On-Chip
Memory
PIC18FX5K22
007FFFh
PIC18F87K22 FAMILY
DS39960C-page 88 2011 Microchip Technology Inc.
6.1 Program Memory Organization
PIC18 microcontrollers implement a 21-bit program
counter that is capable of addressing a 2-Mbyte
program memory space. Accessing a location between
the upper boundary of the physically implemented
memory and the 2-Mbyte address will return all ‘0’s (a
NOP instruction).
The entire PIC18F87K22 family offers a range of
on-chip Flash program memory sizes, from 32 Kbytes
(up to 16,384 single-word instructions) to 128 Kbytes
(65,536 single-word instructions).
• PIC18F65K22 and PIC18F85K22 – 32 Kbytes of
Flash memory, storing up to 16,384 single-word
instructions
• PIC18F66K22 and PIC18F86K22 – 64 Kbytes of
Flash memory, storing up to 32,768 single-word
instructions
• PIC18F67K22 and PIC18F87K22 – 128 Kbytes of
Flash memory, storing up to 65,536 single-word
instructions
The program memory maps for individual family
members are shown in Figure 6-1.
6.1.1 HARD MEMORY VECTORS
All PIC18 devices have a total of three hard-coded
return vectors in their program memory space. The
Reset vector address is the default value to which the
program counter returns on all device Resets; it is
located at 0000h.
PIC18 devices also have two interrupt vector
addresses for handling high-priority and low-priority
interrupts. The high-priority interrupt vector is located at
0008h and the low-priority interrupt vector is at 0018h.
The locations of these vectors are shown, in relation to
the program memory map, in Figure 6-2.
FIGURE 6-2: HARD VECTOR FOR
PIC18F87K22 FA MILY
DEVICES
Reset Vector
Low-Priority Interrupt Vector
0000h
0018h
On-Chip
Program Memory
High-Priority Interrupt Vector 0008h
1FFFFFh
Read ‘0’
Legend: (Top of Memory) represents upper boundary
of on-chip program memory space (see
Figure 6-1 for device-specific values).
Shaded area represents unimplemented
memory. Areas are not shown to scale.
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6.1.2 PROGRAM COUNTER
The Program Counter (PC) specifies the address of the
instruction to fetch for execution. The PC is 21 bits wide
and contained in three separate 8-bit registers.
The low byte, known as the PCL register, is both
readable and writable. The high byte, or PCH register,
contains the PC<15:8> bits and is not directly readable
or writable. Updates to the PCH register are performed
through the PCLATH register. The upper byte is called
PCU. This register contains the PC<20:16> bits; it is
also not directly readable or writable. Updates to the
PCU register are performed through the PCLATU
register.
The contents of PCLATH and PCLATU are transferred
to the program counter by any operation that writes
PCL. Similarly, the upper two bytes of the program
counter are transferred to PCLATH and PCLATU by an
operation that reads PCL. This is useful for computed
offsets to the PC (see Section 6.1.5.1 “Computed
GOTO”).
The PC addresses bytes in the program memory. To
prevent the PC from becoming misaligned with word
instructions, the Least Significant bit of PCL is fixed to
a value of ‘0’. The PC increments by two to address
sequential instructions in the program memory.
The CALL, RCALL, GOTO and program branch
instructions write to the program counter directly. For
these instructions, the contents of PCLATH and
PCLATU are not transferred to the program counter.
6.1.3 RETURN ADDRESS STACK
The return address stack enables execution of any
combination of up to 31 program calls and interrupts.
The PC is pushed onto the stack when a CALL or
RCALL instruction is executed or an interrupt is
Acknowledged. The PC value is pulled off the stack on
a RETURN, RETLW or a RETFIE instruction. The value
also is pulled off the stack on ADDULNK and SUBULNK
instructions, if the extended instruction set is enabled.
PCLATU and PCLATH are not affected by any of the
RETURN or CALL instructions.
The stack operates as a 31-word by 21-bit RAM and a
5-bit Stack Pointer, STKPTR. The stack space is not
part of either program or data space. The Stack Pointer
is readable and writable and the address on the top of
the stack is readable and writable through the
Top-of-Stack Special Function Registers. Data can also
be pushed to, or popped from, the stack using these
registers.
A CALL type instruction causes a push onto the stack.
The Stack Pointer is first incremented and the location
pointed to by the Stack Pointer is written with the
contents of the PC (already pointing to the instruction
following the CALL). A RETURN type instruction causes
a pop from the stack. The contents of the location
pointed to by the STKPTR are transferred to the PC
and then the Stack Pointer is decremented.
The Stack Pointer is initialized to ‘00000’ after all
Resets. There is no RAM associated with the location
corresponding to a Stack Pointer value of ‘00000’; this
is only a Reset value. Status bits indicate if the stack is
full, has overflowed or has underflowed.
6.1.3.1 Top-of-Stack Access
Only the top of the return address stack (TOS) is
readable and writable. A set of three registers,
TOSU:TOSH:TOSL, holds the contents of the stack
location pointed to by the STKPTR register
(Figure 6-3). This allows users to implement a software
stack, if necessary. After a CALL, RCALL or interrupt (or
ADDULNK and SUBULNK instructions, if the extended
instruction set is enabled), the software can read the
pushed value by reading the TOSU:TOSH:TOSL regis-
ters. These values can be placed on a user-defined
software stack. At return time, the software can return
these values to TOSU:TOSH:TOSL and do a return.
While accessing the stack, users must disable the
global interrupt enable bits to prevent inadvertent stack
corruption.
FIGURE 6-3: RETUR N ADDR ESS ST A C K AND AS SOC IA TED RE GIS TER S
00011
001A34h
11111
11110
11101
00010
00001
00000
00010
Return Address Stack <20:0>
Top-of-Stack
000D58h
TOSLTOSHTOSU
34h1Ah00h
STKPTR<4:0>
Top-of-Stack Registers Stack Pointer
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6.1.3.2 Return Stack Pointer (STKPTR)
The STKPTR register (Register 6-1) contains the Stack
Pointer value, the STKFUL (Stack Full) status bit and
the STKUNF (Stack Underflow) status bits. The value
of the Stack Pointer can be 0 through 31. The Stack
Pointer increments before values are pushed onto the
stack and decrements after values are popped off the
stack. On Reset, the Stack Pointer value will be zero.
The user may read and write the Stack Pointer value.
This feature can be used by a Real-Time Operating
System (RTOS) for return-stack maintenance.
After the PC is pushed onto the stack 31 times (without
popping any values off the stack), the STKFUL bit is
set. The STKFUL bit is cleared by software or by a
POR.
What happens when the stack becomes full depends
on the state of the STVREN (Stack Overflow Reset
Enable) Configuration bit. (For a description of the
device Configuration bits, see Section 28.1 “Confi gu-
ration Bit s”.) If STVREN is set (default), the 31st push
will push the (PC + 2) value onto the stack, set the
STKFUL bit and reset the device. The STKFUL bit will
remain set and the Stack Pointer will be set to zero.
If STVREN is cleared, the STKFUL bit will be set on the
31st push and the Stack Pointer will increment to 31.
Any additional pushes will not overwrite the 31st push
and the STKPTR will remain at 31.
When the stack has been popped enough times to
unload the stack, the next pop will return a value of zero
to the PC and set the STKUNF bit, while the Stack
Pointer remains at zero. The STKUNF bit will remain
set until cleared by software or until a POR occurs.
6.1.3.3 PUSH and POP Instructions
Since the Top-of-Stack is readable and writable, the
ability to push values onto the stack and pull values off
the stack, without disturbing normal program execu-
tion, is a desirable feature. The PIC18 instruction set
includes two instructions, PUSH and POP, that permit
the TOS to be manipulated under software control.
TOSU, TOSH and TOSL can be modified to place data
or a return address on the stack.
The PUSH instruction places the current PC value onto
the stack. This increments the Stack Pointer and loads
the current PC value onto the stack.
The POP instruction discards the current TOS by
decrementing the Stack Pointer. The previous value
pushed onto the stack then becomes the TOS value.
Note: Returning a value of zero to the PC on an
underflow has the effect of vectoring the
program to the Reset vector, where the
stack conditions can be verified and
appropriate actions can be taken. This is
not the same as a Reset, as the contents
of the SFRs are not affected.
REGISTER 6-1: STKPTR: STACK POINTER REGISTER
R/C-0 R/C-0 U-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0
STKFUL(1) STKUNF(1) — SP4 SP3 SP2 SP1 SP0
bit 7 bit 0
Legend: C = Clearable bit
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 STKFUL: Stack Full Flag bit(1)
1 = Stack has become full or overflowed
0 = Stack has not become full or overflowed
bit 6 STKUNF: Stack Underflow Flag bit(1)
1 = Stack underflow has occurred
0 = Stack underflow did not occur
bit 5 Unimplemented: Read as ‘0’
bit 4-0 SP<4:0>: Stack Pointer Location bits
Note 1: Bit 7 and bit 6 are cleared by user software or by a POR.
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6.1.3.4 Stack Full and Underflow Resets
Device Resets on stack overflow and stack underflow
conditions are enabled by setting the STVREN bit
(CONFIG4L<0>). When STVREN is set, a full or under-
flow condition will set the appropriate STKFUL or
STKUNF bit and then cause a device Reset. When
STVREN is cleared, a full or underflow condition will set
the appropriate STKFUL or STKUNF bit, but not cause
a device Reset. The STKFUL or STKUNF bits are
cleared by the user software or a Power-on Reset.
6.1.4 FAST REGISTER STACK
A Fast Register Stack is provided for the STATUS,
WREG and BSR registers to provide a “fast return”
option for interrupts. This stack is only one level deep
and is neither readable nor writable. It is loaded with the
current value of the corresponding register when the
processor vectors for an interrupt. All interrupt sources
will push values into the Stack registers. The values in
the registers are then loaded back into the working
registers if the RETFIE,FAST instruction is used to
return from the interrupt.
If both low and high-priority interrupts are enabled, the
Stack registers cannot be used reliably to return from
low-priority interrupts. If a high-priority interrupt occurs
while servicing a low-priority interrupt, the Stack
register values stored by the low-priority interrupt will
be overwritten. In these cases, users must save the key
registers in software during a low-priority interrupt.
If interrupt priority is not used, all interrupts may use the
Fast Register Stack for returns from interrupt. If no
interrupts are used, the Fast Register Stack can be
used to restore the STATUS, WREG and BSR registers
at the end of a subroutine call. To use the Fast Register
Stack for a subroutine call, a CALL label,FAST
instruction must be executed to save the STATUS,
WREG and BSR registers to the Fast Register Stack. A
RETURN,FAST instruction is then executed to restore
these registers from the Fast Register Stack.
Example 6-1 shows a source code example that uses
the Fast Register Stack during a subroutine call and
return.
EXAMPLE 6-1: FAST REGISTER STACK
CODE EXAMPLE
6.1.5 LOOK-UP TABLES IN PROGRAM
MEMORY
There may be programming situations that require the
creation of data structures, or look-up tables, in
program memory. For PIC18 devices, look-up tables
can be implemented in two ways:
• Computed GOTO
• Table Reads
6.1.5.1 Computed GOTO
A computed GOTO is accomplished by adding an offset
to the program counter. An example is shown in
Example 6-2.
A look-up table can be formed with an ADDWF PCL
instruction and a group of RETLW nn instructions. The
W register is loaded with an offset into the table before
executing a call to that table. The first instruction of the
called routine is the ADDWF PCL instruction. The next
instruction executed will be one of the RETLW nn
instructions that returns the value ‘nn’ to the calling
function.
The offset value (in WREG) specifies the number of
bytes that the program counter should advance and
should be multiples of two (LSb = 0).
In this method, only one data byte may be stored in
each instruction location and room on the return
address stack is required.
EXAMPLE 6-2: COMPUTED GOTO USING
AN OFFSET VALUE
6.1.5.2 Table Reads
A better method of storing data in program memory
allows two bytes of data to be stored in each instruction
location.
Look-up table data may be stored two bytes per
program word while programming. The Table Pointer
(TBLPTR) specifies the byte address and the Table
Latch (TABLAT) contains the data that is read from the
program memory. Data is transferred from program
memory one byte at a time.
The table read operation is discussed further in
Section 7.1 “Table Reads and Table Writes”.
CALL SUB1, FAST ;STATUS, WREG, BSR
;SAVED IN FAST REGISTER
;STACK
SUB1
RETURN FAST ;RESTORE VALUES SAVED
;IN FAST REGISTER STACK
MOVF OFFSET, W
CALL TABLE
ORG nn00h
TABLE ADDWF PCL
RETLW nnh
RETLW nnh
RETLW nnh
.
.
.
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DS39960C-page 92 2011 Microchip Technology Inc.
6.2 PIC18 Instruction Cycle
6.2.1 CLOCKING SCHEME
The microcontroller clock input, whether from an
internal or external source, is internally divided by four
to generate four non-overlapping quadrature clocks
(Q1, Q2, Q3 and Q4). Internally, the program counter is
incremented on every Q1, with the instruction fetched
from the program memory and latched into the
Instruction Register (IR) during Q4.
The instruction is decoded and executed during the
following Q1 through Q4. The clocks and instruction
execution flow are shown in Figure 6-4.
6.2.2 INSTRUCTION FLOW/PIPELINING
An “Instruction Cycle” consists of four Q cycles, Q1
through Q4. The instruction fetch and execute are pipe-
lined in such a manner that a fetch takes one instruction
cycle, while the decode and execute take another
instruction cycle. However, due to the pipelining, each
instruction effectively executes in one cycle. If an
instruction (such as GOTO) causes the program counter
to change, two cycles are required to complete the
instruction. (See Example 6-3.)
A fetch cycle begins with the Program Counter (PC)
incrementing in Q1.
In the execution cycle, the fetched instruction is latched
into the Instruction Register (IR) in cycle Q1. This
instruction is then decoded and executed during the
Q2, Q3 and Q4 cycles. Data memory is read during Q2
(operand read) and written during Q4 (destination
write).
FIGURE 6-4: CLOCK/INSTRUCTION CYCLE
EXAMPLE 6-3: INSTRUCTION PIPELINE FLOW
Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4
OSC1
Q1
Q2
Q3
Q4
PC
OSC2/CLKO
(RC mode)
PC PC + 2 PC + 4
Fetch INST (PC)
Execute INST (PC – 2)
Fetch INST (PC + 2)
Execute INST (PC)
Fetch INST (PC + 4)
Execute INST (PC + 2)
Internal
Phase
Clock
All instructions are single cycle, except for any program branches. These take two cycles since the fetch instruction
is “flushed” from the pipeline while the new instruction is being fetched and then executed.
TCY0TCY1TCY2TCY3TCY4TCY5
1. MOVLW 55h Fetch 1 Execute 1
2. MOVWF PORTB Fetch 2 Execute 2
3. BRA SUB_1 Fetch 3 Execute 3
4. BSF PORTA, BIT3 (Forced NOP) Fetch 4 Flush (NOP)
5. Instruction @ address SUB_1 Fetch SUB_1 Execute SUB_1
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6.2.3 INSTRUCTIONS IN PROGRAM
MEMORY
The program memory is addressed in bytes. Instruc-
tions are stored as two or four bytes in program
memory. The Least Significant Byte of an instruction
word is always stored in a program memory location
with an even address (LSB = 0). To maintain alignment
with instruction boundaries, the PC increments in steps
of two and the LSB will always read ‘0’ (see
Section 6.1.2 “Program Counter”).
Figure 6-5 shows an example of how instruction words
are stored in the program memory.
The CALL and GOTO instructions have the absolute
program memory address embedded into the instruc-
tion. Since instructions are always stored on word
boundaries, the data contained in the instruction is a
word address. The word address is written to PC<20:1>
which accesses the desired byte address in program
memory. Instruction #2 in Figure 6-5 shows how the
instruction, GOTO 0006h, is encoded in the program
memory. Program branch instructions, which encode a
relative address offset, operate in the same manner. The
offset value stored in a branch instruction represents the
number of single-word instructions that the PC will be
offset by. For more details on the instruction set, see
Section 29.0 “Instruction Set Summary”.
FIGURE 6-5: INSTRUCTIONS IN PROGRAM MEMORY
6.2.4 TWO-WORD INSTRUCTIONS
The standard PIC18 instruction set has four, two-word
instructions: CALL, MOVFF, GOTO and LSFR. In all
cases, the second word of the instructions always has
‘1111’ as its four Most Significant bits. The other 12 bits
are literal data, usually a data memory address.
The use of ‘1111’ in the 4 MSbs of an instruction
specifies a special form of NOP. If the instruction is
executed in proper sequence, immediately after the
first word, the data in the second word is accessed and
used by the instruction sequence. If the first word is
skipped, for some reason, and the second word is
executed by itself, a NOP is executed instead. This is
necessary for cases when the two-word instruction is
preceded by a conditional instruction that changes the
PC. Example 6-4 shows how this works.
EXAMPLE 6-4: TWO-WORD INSTRUCTIONS
Word Address
LSB = 1LSB = 0
Program Memory
Byte Locations
000000h
000002h
000004h
000006h
Instruction 1: MOVLW 055h 0Fh 55h 000008h
Instruction 2: GOTO 0006h EFh 03h 00000Ah
F0h 00h 00000Ch
Instruction 3: MOVFF 123h, 456h C1h 23h 00000Eh
F4h 56h 000010h
000012h
000014h
Note: For information on two-word instructions
in the extended instruction set, see
Section 6.5 “Program Memory and the
Extended Instruction Set”.
CASE 1:
Object Code Source Code
0110 0110 0000 0000 TSTFSZ REG1 ; is RAM location 0?
1100 0001 0010 0011 MOVFF REG1, REG2 ; No, skip this word
1111 0100 0101 0110 ; Execute this word as a NOP
0010 0100 0000 0000 ADDWF REG3 ; continue code
CASE 2:
Object Code Source Code
0110 0110 0000 0000 TSTFSZ REG1 ; is RAM location 0?
1100 0001 0010 0011 MOVFF REG1, REG2 ; Yes, execute this word
1111 0100 0101 0110 ; 2nd word of instruction
0010 0100 0000 0000 ADDWF REG3 ; continue code
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6.3 Data Memory Organization
The data memory in PIC18 devices is implemented as
static RAM. Each register in the data memory has a
12-bit address, allowing up to 4,096 bytes of data
memory. The memory space is divided into as many as
16 banks that contain 256 bytes each. PIC18FX6K22
and PIC18FX7K22 devices implement all 16 complete
banks, for a total of 4 Kbytes. PIC18FX5K22 devices
implement only the first eight complete banks, for a
total of 2 Kbytes.
Figure 6-6 and Figure 6-7 show the data memory
organization for the devices.
The data memory contains Special Function Registers
(SFRs) and General Purpose Registers (GPRs). The
SFRs are used for control and status of the controller
and peripheral functions, while GPRs are used for data
storage and scratchpad operations in the user’s
application. Any read of an unimplemented location will
read as ‘0’s.
The instruction set and architecture allow operations
across all banks. The entire data memory may be
accessed by Direct, Indirect or Indexed Addressing
modes. Addressing modes are discussed later in this
section.
To ensure that commonly used registers (select SFRs
and select GPRs) can be accessed in a single cycle,
PIC18 devices implement an Access Bank. This is a
256-byte memory space that provides fast access to
select SFRs and the lower portion of GPR Bank 0 with-
out using the Bank Select Register. For details on the
Access RAM, see Section 6.3.2 “Acc es s Bank”.
6.3.1 BANK SELECT REGISTER
Large areas of data memory require an efficient
addressing scheme to make it possible for rapid access
to any address. Ideally, this means that an entire
address does not need to be provided for each read or
write operation. For PIC18 devices, this is accom-
plished with a RAM banking scheme. This divides the
memory space into 16 contiguous banks of 256 bytes.
Depending on the instruction, each location can be
addressed directly by its full 12-bit address, or an
eight-bit, low-order address and a four-bit Bank Pointer.
Most instructions in the PIC18 instruction set make use
of the Bank Pointer, known as the Bank Select Register
(BSR). This SFR holds the four Most Significant bits of
a location’s address. The instruction itself includes the
eight Least Significant bits. Only the four lower bits of
the BSR are implemented (BSR<3:0>). The upper four
bits are unused, always read as ‘0’ and cannot be
written to. The BSR can be loaded directly by using the
MOVLB instruction.
The value of the BSR indicates the bank in data
memory. The eight bits in the instruction show the loca-
tion in the bank and can be thought of as an offset from
the bank’s lower boundary. The relationship between
the BSR’s value and the bank division in data memory
is shown in Figure 6-7.
Since up to 16 registers may share the same low-order
address, the user must always be careful to ensure that
the proper bank is selected before performing a data
read or write. For example, writing what should be
program data to an eight-bit address of F9h, while the
BSR is 0Fh, will end up resetting the program counter.
While any bank can be selected, only those banks that
are actually implemented can be read or written to.
Writes to unimplemented banks are ignored, while
reads from unimplemented banks will return ‘0’s. Even
so, the STATUS register will still be affected as if the
operation was successful. The data memory map in
Figure 6-6 indicates which banks are implemented.
In the core PIC18 instruction set, only the MOVFF
instruction fully specifies the 12-bit address of the
source and target registers. When this instruction
executes, it ignores the BSR completely. All other
instructions include only the low-order address as an
operand and must use either the BSR or the Access
Bank to locate their target registers.
Note: The operation of some aspects of data
memory are changed when the PIC18
extended instruction set is enabled. See
Section 6.6 “Data Memory and the
Extended Instruction Set” for more
information.
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FIGURE 6-6: DATA MEMORY MAP FOR PIC18FX5K22 AND PIC18FX7K22 DEVICES
00h
5Fh
60h
FFh
Access Bank
When a = 0:
The BSR is ignored and the
Access Bank is used.
The first 96 bytes are general
purpose RAM (from Bank 0).
The second 160 bytes are
Special Function Registers
(from Bank 15).
When a = 1:
The BSR specifies the bank
used by the instruction.
Access RAM High
Access RAM Low
(SFRs)
Bank 0
Bank 1
Bank 14
Bank 15
Data Memory Map
BSR<3:0>
= 0000
= 0001
= 1111
060h
05Fh
F60h
FFFh
F5Fh
F00h
EFFh
1FFh
100h
0FFh
000h
Access RAM
FFh
00h
FFh
00h
FFh
00h
GPR
GPR
SFR
Bank 2
= 0010
2FFh
200h
Bank 3
FFh
00h
GPR
FFh
= 0011
GPR(1,2)
GPR
GPR
GPR
GPR
GPR
4FFh
400h
5FFh
500h
3FFh
300h
FFh
00h
FFh
00h
FFh
00h
FFh
00h
FFh
00h
00h
= 0110
= 0111
= 0101
= 0100 Bank 4
Bank 5
Bank 6
Bank 7
Bank 8
= 1110
6FFh
600h
7FFh
700h
800h
Bank 9
Bank 10
Bank 11
Bank 12
Bank 13
8FFh
900h
9FFh
A00h
AFFh
B00h
BFFh
C00h
CFFh
D00h
DFFh
E00h
FFh
00h
FFh
00h
FFh
00h
FFh
00h
FFh
00h
FFh
00h
GPR(2)
GPR(2)
GPR(2)
GPR(2)
GPR(2)
GPR(2)
GPR(2)
Note 1: Addresses, F16h through F5Fh, are also used by SFRs, but are not part of the Access RAM. Users must
always use the complete address, or load the proper BSR value, to access these registers.
2: These addresses are unused for devices with 32 Kbytes of program memory (PIC18FX5K22). For those
devices, read these addresses at 00h.
= 1000
= 1001
= 1010
= 1011
= 1100
= 1101
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FIGURE 6-7: USE OF THE BANK SELECT REGISTER (DIRECT ADDRESSING)
6.3.2 ACCESS BANK
While the use of the BSR, with an embedded 8-bit
address, allows users to address the entire range of data
memory, it also means that the user must ensure that the
correct bank is selected. If not, data may be read from,
or written to, the wrong location. This can be disastrous
if a GPR is the intended target of an operation, but an
SFR is written to instead. Verifying and/or changing the
BSR for each read or write to data memory can become
very inefficient.
To streamline access for the most commonly used data
memory locations, the data memory is configured with
an Access Bank, which allows users to access a
mapped block of memory without specifying a BSR.
The Access Bank consists of the first 96 bytes of
memory (00h-5Fh) in Bank 0 and the last 160 bytes of
memory (60h-FFh) in Bank 15. The lower half is known
as the “Access RAM” and is composed of GPRs. The
upper half is where the device’s SFRs are mapped.
These two areas are mapped contiguously in the
Access Bank and can be addressed in a linear fashion
by an eight-bit address (Figure 6-6).
The Access Bank is used by core PIC18 instructions
that include the Access RAM bit (the ‘a’ parameter in
the instruction). When ‘a’ is equal to ‘1’, the instruction
uses the BSR and the 8-bit address included in the
opcode for the data memory address. When ‘a’ is ‘0’,
however, the instruction is forced to use the Access
Bank address map. In that case, the current value of
the BSR is ignored entirely.
Using this “forced” addressing allows the instruction to
operate on a data address in a single cycle without
updating the BSR first. For 8-bit addresses of 60h and
above, this means that users can evaluate and operate
on SFRs more efficiently. The Access RAM below 60h
is a good place for data values that the user might need
to access rapidly, such as immediate computational
results or common program variables.
Access RAM also allows for faster and more code
efficient context saving and switching of variables.
The mapping of the Access Bank is slightly different
when the extended instruction set is enabled (XINST
Configuration bit = 1). This is discussed in more detail
in Section 6.6.3 “Mapping the Access Bank in
Indexed Literal Offset Mode”.
6.3.3 GENERAL PURPOSE
REGISTER FILE
PIC18 devices may have banked memory in the GPR
area. This is data RAM which is available for use by all
instructions. GPRs start at the bottom of Bank 0
(address 000h) and grow upwards towards the bottom of
the SFR area. GPRs are not initialized by a Power-on
Reset and are unchanged on all other Resets.
Note 1: The Access RAM bit of the instruction can be used to force an override of the selected bank (BSR<3:0>)
to the registers of the Access Bank.
2: The MOVFF instruction embeds the entire 12-bit address in the instruction.
Data Memory
Bank Select(2)
70
From Opcode(2)
0000
000h
100h
200h
300h
F00h
E00h
FFFh
Bank 0
Bank 1
Bank 2
Bank 14
Bank 15
00h
FFh
00h
FFh
00h
FFh
00h
FFh
00h
FFh
00h
FFh
Bank 3
through
Bank 13
0010 11111111
70
BSR(1)
11111111
2011 Microchip Technology Inc. DS39960C-page 97
PIC18F87K22 FAMILY
6.3.4 SPECIAL FUNCTION REGISTERS
The Special Function Registers (SFRs) are registers
used by the CPU and peripheral modules for controlling
the desired operation of the device. These registers are
implemented as static RAM. SFRs start at the top of
data memory (FFFh) and extend downward to occupy
all of Bank 15 (F00h to FFFh) and the top part of
Bank 14 (EF4h to EFFh).
A list of these registers is given in Table 6- 1 and
Table 6-2.
The SFRs can be classified into two sets: those
associated with the “core” device functionality (ALU,
Resets and interrupts) and those related to the
peripheral functions. The Reset and Interrupt registers
are described in their respective chapters, while the
ALU’s STATUS register is described later in this section.
Registers related to the operation of the peripheral
features are described in the chapter for that peripheral.
The SFRs are typically distributed among the
peripherals whose functions they control. Unused SFR
locations are unimplemented and read as ‘0’s.
TABLE 6-1: SPECIAL FUNCT ION REG ISTER MAP FOR PIC18F 87K22 FAMILY
Addr. Name Addr. Name Addr. Name Addr. Name Addr. Name Addr. Name
FFFh TOSU FDFh INDF2(1) FBFh ECCP1AS F9Fh IPR1 F7Fh EECON1 F5Fh RTCCFG
FFEh TOSH FDEh POSTINC2(1) FBEh ECCP1DEL F9Eh PIR1 F7Eh EECON2 F5Eh RTCCAL
FFDh TOSL FDDh POSTDEC2(1) FBDh CCPR1H F9Dh PIE1 F7Dh TMR5H F5Dh RTCVALH
FFCh STKPTR FDCh PREINC2(1) FBCh CCPR1L F9Ch PSTR1CON F7Ch TMR5L F5Ch RTCVALL
FFBh PCLATU FDBh PLUSW2(1) FBBh CCP1CON F9Bh OSCTUNE F7Bh T5CON F5Bh ALRMCFG
FFAh PCLATH FDAh FSR2H FBAh PIR5 F9Ah TRISJ(3) F7Ah T5GCON F5Ah ALRMRPT
FF9h PCL FD9h FSR2L FB9h PIE5 F99h TRISH(3) F79h CCPR4H F59h ALRMVALH
FF8h TBLPTRU FD8h STATUS FB8h IPR4 F98h TRISG F78h CCPR4L F58h ALRMVALL
FF7h TBLPTRH FD7h TMR0H FB7h PIR4 F97h TRISF F77h CCP4CON F57h CTMUCONH
FF6h TBLPTRL FD6h TMR0L FB6h PIE4 F96h TRISE F76h CCPR5H F56h CTMUCONL
FF5h TABLAT FD5h T0CON FB5h CVRCON F95h TRISD F75h CCPR5L F55h CTMUICONH
FF4h PRODH FD4h SPBRGH1 FB4h CMSTAT F94h TRISC F74h CCP5CON F54h CM1CON
FF3h PRODL FD3h OSCCON FB3h TMR3H F93h TRISB F73h CCPR6H F53h PADCFG1
FF2h INTCON FD2h IPR5 FB2h TMR3L F92h TRISA F72h CCPR6L F52h ECCP2AS
FF1h INTCON2 FD1h WDTCON FB1h T3CON F91h LATJ(3) F71h CCP6CON F51h ECCP2DEL
FF0h INTCON3 FD0h RCON FB0h T3GCON F90h LATH(3) F70h CCPR7H F50h CCPR2H
FEFh INDF0(1) FCFh TMR1H FAFh SPBRG1 F8Fh LATG F6Fh CCPR7L F4Fh CCPR2L
FEEh POSTINC0(1) FCEh TMR1L FAEh RCREG1 F8Eh LATF F6Eh CCP7CON F4Eh CCP2CON
FEDh POSTDEC0(1) FCDh T1CON FADh TXREG1 F8Dh LATE F6Dh TMR4 F4Dh ECCP3AS
FECh PREINC0(1) FCCh TMR2 FACh TXSTA1 F8Ch LATD F6Ch PR4 F4Ch ECCP3DEL
FEBh PLUSW0(1) FCBh PR2 FABh RCSTA1 F8Bh LATC F6Bh T4CON F4Bh CCPR3H
FEAh FSR0H FCAh T2CON FAAh T1GCON F8Ah LATB F6Ah SSP2BUF F4Ah CCPR3L
FE9h FSR0L FC9h SSP1BUF FA9h IPR6 F89h LATA F69h SSP2ADD F49h CCP3CON
FE8h WREG FC8h SSP1ADD FA8h HLVDCON F88h PORTJ(3) F68h SSP2STAT F48h CCPR8H
FE7h INDF1(1) FC7h SSP1STAT FA7h PSPCON F87h PORTH(3) F67h SSP2CON1 F47h CCPR8L
FE6h POSTINC1(1) FC6h SSP1CON1 FA6h PIR6 F86h PORTG F66h SSP2CON2 F46h CCP8CON
FE5h POSTDEC1(1) FC5h SSP1CON2 FA5h IPR3 F85h PORTF F65h BAUDCON1 F45h CCPR9H(4)
FE4h PREINC1(1) FC4h ADRESH FA4h PIR3 F84h PORTE F64h OSCCON2 F44h CCPR9L(4)
FE3h PLUSW1(1) FC3h ADRESL FA3h PIE3 F83h PORTD F63h EEADRH F43h CCP9CON(4)
FE2h FSR1H FC2h ADCON0 FA2h IPR2 F82h PORTC F62h EEADR F42h CCPR10H(4)
FE1h FSR1L FC1h ADCON1 FA1h PIR2 F81h PORTB F61h EEDATA F41h CCPR10L(4)
FE0h BSR FC0h ADCON2 FA0h PIE2 F80h PORTA F60h PIE6 F40h CCP10CON(4)
Note 1: This is not a physical register.
2: Unimplemented registers are read as ‘0’.
3: Unimplemented on 64-pin devices (PIC18F6XK22), read as ‘0’.
4: This register is not available on devices with a program memory of 32 Kbytes (PIC18FX5K22).
5: Addresses, F16h through F5Fh, are also used by SFRs, but are not part of the Access RAM. To access these registers,
users must always load the proper BSR value.
PIC18F87K22 FAMILY
DS39960C-page 98 2011 Microchip Technology Inc.
F3Fh TMR7H(4) F32h TMR12(4) F25h ANCON0 F18h PMD1
F3Eh TMR7L(4) F31h PR12(4) F24h ANCON1 F17h PMD2
F3Dh T7CON(4) F30h T12CON(4) F23h ANCON2 F16h PMD3
F3Ch T7GCON(4) F2Fh CM2CON F22h RCSTA2
F3Bh TMR6 F2Eh CM3CON F21h TXSTA2
F3Ah PR6 F2Dh CCPTMRS0 F20h BAUDCON2
F39H T6CON F2Ch CCPTMRS1 F1Fh SPBRGH2
F38h TMR8 F2Bh CCPTMRS2 F1Eh SPBRG2
F37h PR8 F2Ah REFOCON F1Dh RCREG2
F36h T8CON F29H ODCON1 F1Ch TXREG2
F35h TMR10(4) F28h ODCON2 F1Bh PSTR2CON
F34h PR10(4) F27h ODCON3 F1Ah PSTR3CON
F33h T10CON(4) F26h MEMCON(3) F19h PMD0
TABLE 6-2: PIC18F87K22 FAMILY REGISTER FILE SUMMARY
Address File Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Value on
POR, BOR
FFFh TOSU — — — Top-of-Stack Upper Byte (TOS<20:16>) ---0 0000
FFEh TOSH Top-of-Stack High Byte (TOS<15:8>) 0000 0000
FFDh TOSL Top-of-Stack Low Byte (TOS<7:0>) 0000 0000
FFCh STKPTR STKFUL STKUNF — Return Stack Pointer uu-0 0000
FFBh PCLATU — — — Holding Register for PC<20:16> ---0 0000
FFAh PCLATH Holding Register for PC<15:8> 0000 0000
FF9h PCL PC Low Byte (PC<7:0>) 0000 0000
FF8h TBLPTRU —— bit 21 Program Memory Table Pointer Upper Byte (TBLPTR<20:16>) --00 0000
FF7h TBLPTRH Program Memory Table Pointer High Byte (TBLPTR<15:8>) 0000 0000
FF6h TBLPTRL Program Memory Table Pointer Low Byte (TBLPTR<7:0>) 0000 0000
FF5h TABLAT Program Memory Table Latch 0000 0000
FF4h PRODH Product Register High Byte xxxx xxxx
FF3h PRODL Product Register Low Byte xxxx xxxx
FF2h INTCON GIE/GIEH PEIE/GIEL TMR0IE INT0IE RBIE TMR0IF INT0IF RBIF 0000 000x
FF1h INTCON2 RBPU INTEDG0 INTEDG1 INTEDG2 INTEDG3 TMR0IP INT3IP RBIP 1111 1111
FF0h INTCON3 INT2IP INT1IP INT3IE INT2IE INT1IE INT3IF INT2IF INT1IF 1100 0000
FEFh INDF0 Uses contents of FSR0 to address data memory – value of FSR0 not changed (not a physical register) ---- ----
FEEh POSTINC0 Uses contents of FSR0 to address data memory – value of FSR0 post-incremented (not a physical register) ---- ----
FEDh POSTDEC0 Uses contents of FSR0 to address data memory – value of FSR0 post-decremented (not a physical register) ---- ----
FECh PREINC0 Uses contents of FSR0 to address data memory – value of FSR0 pre-incremented (not a physical register) ---- ----
FEBh PLUSW0 Uses contents of FSR0 to address data memory – value of FSR0 pre-incremented (not a physical register) – value
of FSR0 offset by W
---- ----
FEAh FSR0H — — — — Indirect Data Memory Address Pointer 0 High ---- 0000
FE9h FSR0L Indirect Data Memory Address Pointer 0 Low Byte xxxx xxxx
FE8h WREG Working Register xxxx xxxx
FE7h INDF1 Uses contents of FSR1 to address data memory – value of FSR1 not changed (not a physical register) ---- ----
Note 1: The bit is available when Master Clear is disabled (MCLRE = 0). When MCLRE is set, the bit is unimplemented.
2: Unimplemented on 64-pin devices (PIC18F6XK22), read as ‘0’.
3: Unimplemented on devices with a program memory of 32 Kbytes (PIC18FX5K22).
TABLE 6-1: SPE CIAL FUNCT ION RE GISTER MAP FOR PIC18F 87K22 FAMILY (CONTINUED)
Addr. Name Addr. Name Addr. Name Addr. Name Addr. Name Addr. Name
Note 1: This is not a physical register.
2: Unimplemented registers are read as ‘0’.
3: Unimplemented on 64-pin devices (PIC18F6XK22), read as ‘0’.
4: This register is not available on devices with a program memory of 32 Kbytes (PIC18FX5K22).
5: Addresses, F16h through F5Fh, are also used by SFRs, but are not part of the Access RAM. To access these registers,
users must always load the proper BSR value.
2011 Microchip Technology Inc. DS39960C-page 99
PIC18F87K22 FAMILY
FE6h POSTINC1 Uses contents of FSR1 to address data memory – value of FSR1 post-incremented (not a physical register) ---- ----
FE5h POSTDEC1 Uses contents of FSR1 to address data memory – value of FSR1 post-decremented (not a physical register) ---- ----
FE4h PREINC1 Uses contents of FSR1 to address data memory – value of FSR1 pre-incremented (not a physical register) ---- ----
FE3h PLUSW1 Uses contents of FSR1 to address data memory – value of FSR1 pre-incremented (not a physical register) – value
of FSR1 offset by W
---- ----
FE2h FSR1H — — — — Indirect Data Memory Address Pointer 1 High ---- xxxx
FE1h FSR1L Indirect Data Memory Address Pointer 1 Low Byte xxxx xxxx
FE0h BSR — — — — Bank Select Register ---- 0000
FDFh INDF2 Uses contents of FSR2 to address data memory – value of FSR2 not changed (not a physical register) ---- ----
FDEh POSTINC2 Uses contents of FSR2 to address data memory – value of FSR2 post-incremented (not a physical register) ---- ----
FDDh POSTDEC2 Uses contents of FSR2 to address data memory – value of FSR2 post-decremented (not a physical register) ---- ----
FDCh PREINC2 Uses contents of FSR2 to address data memory – value of FSR2 pre-incremented (not a physical register) ---- ----
FDBh PLUSW2 Uses contents of FSR2 to address data memory – value of FSR2 pre-incremented (not a physical register) – value
of FSR2 offset by W
---- ----
FDAh FSR2H — — — — Indirect Data Memory Address Pointer 2 High ---- xxxx
FD9h FSR2L Indirect Data Memory Address Pointer 2 Low Byte xxxx xxxx
FD8h STATUS — — —NOVZDCC---x xxxx
FD7h TMR0H Timer0 Register High Byte 0000 0000
FD6h TMR0L Timer0 Register Low Byte xxxx xxxx
FD5h T0CON TMR0ON T08BIT T0CS T0SE PSA TOPS2 TOPS1 TOPS0 1111 1111
FD4h SPBRGH1 USART1 Baud Rate Generator High Byte 0000 0000
FD3h OSCCON IDLEN IRCF2 IRCF1 IRCF0 OSTS HFIOFS SCS1 SCS0 0110 q000
FD2h IPR5 TMR7GIP(3) TMR12IP(3) TMR10IP(3) TMR8IP TMR7IP(3) TMR6IP TMR5IP TMR4IP 1111 11 11
FD1h WDTCON REGSLP —ULPLVLSRETEN— ULPEN ULPSINK SWDTEN 0-x0 -000
FD0h RCON IPEN SBOREN CM RI TO PD POR BOR 0111 11qq
FCFh TMR1H Timer1 Register High Byte xxxx xxxx
FCEh TMR1L Timer1 Register Low Byte xxxx xxxx
FCDh T1CON TMR1CS1 TMR1CS0 T1CKPS1 T1CKPS0 SOSCEN T1SYNC RD16 TMR1ON 0000 0000
FCCh TMR2 Timer2 Register 0000 0000
FCBh PR2 Timer2 Period Register 1111 1111
FCAh T2CON — T2OUTPS3 T2OUTPS2 T2OUTPS1 T2OUTPS0 TMR2ON T2CKPS1 T2CKPS0 -000 0000
FC9h SSP1BUF MSSP Receive Buffer/Transmit Register xxxx xxxx
FC8h SSP1ADD MSSP Address Register in I2C™ Slave Mode. SSP1 Baud Rate Reload Register in I2C Master Mode. 0000 0000
FC7h SSP1STAT SMP CKE D/A PSR/WUA BF 0000 0000
FC6h SSP1CON1 WCOL SSPOV SSPEN CKP SSPM3 SSPM2 SSPM1 SSPM0 0000 0000
FC5h SSP1CON2 GCEN ACKSTAT ACKDT ACKEN RCEN PEN RSEN SEN 0000 0000
FC4h ADRESH A/D Result Register High Byte xxxx xxxx
FC3h ADRESL A/D Result Register Low Byte xxxx xxxx
FC2h ADCON0 — CHS4 CHS3 CHS2 CHS1 CHS0 GO/DONE ADON -000 0000
FC1h ADCON1 TRIGSEL1 TRIGSEL0 VCFG1 VCFG0 VNCFG CHSN2 CHSN1 CHSN0 0000 0000
FC0h ADCON2 ADFM — ACQT2 ACQT1 ACQT0 ADCS2 ADCS1 ADCS0 0-00 0000
FBFh ECCP1AS ECCP1ASE ECCP1AS2 ECCP1AS1 ECCP1AS0 PSS1AC1 PSS1AC0 PSS1BD1 PSS1BD0 0000 0000
FBEh ECCP1DEL P1RSEN P1DC6 P1DC5 P1DC4 P1DC3 P1DC2 P1DC1 P1DC0 0000 0000
FBDh CCPR1H Capture/Compare/PWM Register1 High Byte xxxx xxxx
FBCh CCPR1L Capture/Compare/PWM Register1 Low Byte xxxx xxxx
FBBh CCP1CON P1M1 P1M0 DC1B1 DC1B0 CCP1M3 CCP1M2 CCP1M1 CCP1M0 0000 0000
FBAh PIR5 TMR7GIF(3) TMR12IF(3) TMR10IF(3) TMR8IF TMR7IF(3) TMR6IF TMR5IF TMR4IF 0000 0000
FB9h PIE5 TMR7GIE(3) TMR12IE(3) TMR10IE TMR8IE TMR7IE(3) TMR6IE TMR5IE TMR4IE 0000 0000
FB8h IPR4 CCP10IP(3) CCP9IP(3) CCP8IP CCP7IP CCP6IP CCP5IP CCP4IP CCP3IP 1111 1111
FB7h PIR4 CCP10IF(3) CCP9IF(3) CCP8IF CCP7IF CCP6IF CCP5IF CCP4IF CCP3IF 0000 0000
TABLE 6-2: PIC18F87K22 FAMILY REGISTER FILE SUMMARY (CONTINUED)
Address File Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Value on
POR, BOR
Note 1: The bit is available when Master Clear is disabled (MCLRE = 0). When MCLRE is set, the bit is unimplemented.
2: Unimplemented on 64-pin devices (PIC18F6XK22), read as ‘0’.
3: Unimplemented on devices with a program memory of 32 Kbytes (PIC18FX5K22).
PIC18F87K22 FAMILY
DS39960C-page 100 2011 Microchip Technology Inc.
FB6h PIE4 CCP10IE(3) CCP9IE(3) CCP8IE CCP7IE CCP6IE CCP5IE CCP4IE CCP3IE 0000 0000
FB5h CVRCON CVREN CVROE CVRSS CVR4 CVR3 CVR2 CVR1 CVR0 0000 0000
FB4h CMSTAT CMP3OUT CMP2OUT CMP1OUT — — — — — xxx- ----
FB3h TMR3H Timer3 Register High Byte xxxx xxxx
FB2h TMR3L Timer3 Register Low Byte xxxx xxxx
FB1h T3CON TMR3CS1 TMR3CS0 T3CKPS1 T3CKPS0 SOSCEN T3SYNC RD16 TMR3ON 0000 0000
FB0h T3GCON TMR3GE T3GPOL T3GTM T3GSPM T3GGO/
T3DONE
T3GVAL T3GSS1 T3GSS0 0000 0x00
FAFh SPBRG1 USART1 Baud Rate Generator 0000 0000
FAEh RCREG1 USART1 Receive Register 0000 0000
FADh TXREG1 USART1 Transmit Register xxxx xxxx
FACh TXSTA1 CSRC TX9 TXEN SYNC SENDB BRGH TRMT TX9D 0000 0010
FABh RCSTA1 SPEN RX9 SREN CREN ADDEN FERR OERR RX9D 0000 000x
FAAh T1GCON TMR1GE T1GPOL T1GTM T1GSPM T1GGO/
T1DONE
T1GVAL T1GSS1 T1GSS0 0000 0x00
FA9h IPR6 — — — EEIP — CMP3IP CMP2IP CMP1IP ---1 -111
FA8h HLVDCON VDIRMAG BGVST IRVST HLVDEN HLVDL3 HLVDL2 HLVDL1 HLVDL0 0000 0000
FA7h PSPCON IBF OBF IBOV PSPMODE — — — — 0000 ----
FA6h PIR6 — — —EEIF— CMP3IF CMP2IF CMP1IF ---0 -000
FA5h IPR3 TMR5GIP — RC2IP TX2IP CTMUIP CCP2IP CCP1IP RTCCIP 1-11 1111
FA4h PIR3 TMR5GiF — RC2IF TX2IF CTMUIF CCP2IF CCP1IF RTCCIF 0-00 0000
FA3h PIE3 TMR5GIE — RC2IE TX2IE CTMUIE CCP2IE CCP1IE RTCCIE 0-00 0000
FA2h IPR2 OSCFIP — SSP2IP BCL2IP BCL1IP HLVDIP TMR3IP TMR3GIP 1-11 1111
FA1h PIR2 OSCFIF — SSP2IF BCL2IF BCL1IF HLVDIF TMR3IF TMR3GIF 0-10 0000
FA0h PIE2 OSCFIE — SSP2IE BCL2IE BCL1IE HLVDIE TMR3IE TMR3GIE 0-00 0000
F9Fh IPR1 PSPIP ADIP RC1IP TX1IP SSP1IP TMR1GIP TMR2IP TMR1IP 1111 1111
F9Eh PIR1 PSPIF ADIF RC1IF TX1IF SSP1IF TMR1GIF TMR2IF TMR1IF 0000 0000
F9Dh PIE1 PSPIE ADIE RC1IE TX1IE SSP1IE TMR1GIE TMR2IE TMR1IE 0000 0000
F9Ch PSTR1CON CMPL1 CMPL0 — STRSYNC STRD STRC STRB STRA 00-0 0001
F9Bh OSCTUNE INTSRC PLLEN TUN5 TUN4 TUN3 TUN2 TUN1 TUN0 0000 0000
F9Ah TRISJ(2) TRISJ7 TRISJ6 TRISJ5 TRISJ4 TRISJ3 TRISJ2 TRISJ1 TRISJ0 1111 1111
F99h TRISH(2) TRISH7 TRISH6 TRISH5 TRISH4 TRISH3 TRISH2 TRISH1 TRISH0 1111 1111
F98h TRISG — — — TRISG4 TRISG3 TRISG2 TRISG1 TRISG0 ---1 1111
F97h TRISF TRISF7 TRISF6 TRISF5 TRISF4 TRISF3 TRISF2 TRISF1 —1111 111-
F96h TRISE TRISE7 TRISE6 TRISE5 TRISE4 TRISE3 TRISE2 TRISE1 —1111 111-
F95h TRISD TRISD7 TRISD6 TRISD5 TRISD4 TRISD3 TRISD2 TRISD1 TRISD0 1111 1111
F94h TRISC TRISC7 TRISC6 TRISC5 TRISC4 TRISC3 TRISC2 TRISC1 TRISC0 1111 1111
F93h TRISB TRISB7 TRISB6 TRISB5 TRISB4 TRISB3 TRISB2 TRISB1 TRISB0 1111 1111
F92h TRISA TRISA7 TRISA6 TRISA5 TRISA4 TRISA3 TRISA2 TRISA1 TRISA0 1111 1111
F91h LATJ(2) LATJ7 LATJ6 LATJ5 LATJ4 LATJ3 LATJ2 LATJ1 LATJ0 xxxx xxxx
F90h LATH(2) LATH7 LATH6 LATH5 LATH4 LATH3 LATH2 LATH1 LATH0 xxxx xxxx
F8Fh LATG — — — LATG4 LATG3 LATG2 LATG1 LATG0 ---x xxxx
F8Eh LATF LATF7 LATF6 LATF5 LATF4 LATF3 LATF2 LATF1 —xxxx xxx-
F8Dh LATE LATE7 LATE6 LATE5 LATE4 LATE3 LATE2 LATE1 LATE0 xxxx xxxx
F8Ch LATD LATD7 LATD6 LATD5 LATD4 LATD3 LATD2 LATD1 LATD0 xxxx xxxx
F8Bh LATC LATC7 LATC6 LATC5 LATC4 LATC3 LATC2 LATC1 LATC0 xxxx xxxx
F8Ah LATB LATB7 LATB6 LATB5 LATB4 LATB3 LATB2 LATB1 LATB0 xxxx xxxx
F89h LATA LATA7 LATA6 LATA5 LATA4 LATA3 LATA2 LATA1 LATA0 xxxx xxxx
F88h PORTJ(2) RJ7 RJ6 RJ5 RJ4 RJ3 RJ2 RJ1 RJ0 xxxx xxxx
F87h PORTH(2) RH7 RH6 RH5 RH4 RH3 RH2 RH1 RH0 xxxx xxxx
TABLE 6-2: PIC18F87K22 FAMILY REGISTER FILE SUMMARY (CONTINUED)
Address File Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Value on
POR, BOR
Note 1: The bit is available when Master Clear is disabled (MCLRE = 0). When MCLRE is set, the bit is unimplemented.
2: Unimplemented on 64-pin devices (PIC18F6XK22), read as ‘0’.
3: Unimplemented on devices with a program memory of 32 Kbytes (PIC18FX5K22).
2011 Microchip Technology Inc. DS39960C-page 101
PIC18F87K22 FAMILY
F86h PORTG —— RG5 RG4 RG3 RG2 RG1 RG0 --xx xxxx
F85h PORTF RF7 RF6 RF5 RF4 RF3 RF2 RF1 —xxxx xxx-
F84h PORTE RE7 RE6 RE5 RE4 RE3 RE2 RE1 RE0 xxxx xxxx
F83h PORTD RD7 RD6 RD5 RD4 RD3 RD2 RD1 RD0 xxxx xxxx
F82h PORTC RC7 RC6 RC5 RC4 RC3 RC2 RC1 RC0 xxxx xxxx
F81h PORTB RB7 RB6 RB5 RB4 RB3 RB2 RB1 RB0 xxxx xxxx
F80h PORTA RA7 RA6 RA5 RA4 RA3 RA2 RA1 RA0 xxxx xxxx
F7Fh EECON1 EEPGD CFGS — FREE WRERR WREN WR RD xx-0 x000
F7Eh EECON2 EEPROM Control Register 2 (not a physical register) ---- ----
F7Dh TMR5H Timer5 Register High Byte xxxx xxxx
F7Ch TMR5L Timer5 Register Low Byte xxxx xxxx
F7Bh T5CON TMR5CS1 TMR5CS0 T5CKPS1 T5CKPS0 SOSCEN T5SYNC RD16 TMR5ON 0000 0000
F7Ah T5GCON TMR5GE T5GPOL T5GTM T5GSPM T5GGO/
T5DONE
T5GVAL T5GSS1 T5GSS0 0000 0x00
F79h CCPR4H Capture/Compare/PWM Register 4 High Byte xxxx xxxx
F78h CCPR4L Capture/Compare/PWM Register 4 Low Byte xxxx xxxx
F77h CCP4CON —— DC4B1 DC4B0 CCP4M3 CCP4M2 CCP4M1 CCP4M0 --00 0000
F76h CCPR5H Capture/Compare/PWM Register 5 High Byte xxxx xxxx
F75h CCPR5L Capture/Compare/PWM Register 5 Low Byte xxxx xxxx
F74h CCP5CON —— DC5B1 DC5B0 CCP5M3 CCP5M2 CCP5M1 CCP5M0 --00 0000
F73h CCPR6H Capture/Compare/PWM Register 6 High Byte xxxx xxxx
F72h CCPR6L Capture/Compare/PWM Register 6 Low Byte xxxx xxxx
F71h CCP6CON —— DC6B1 DC6B0 CCP6M3 CCP6M2 CCP6M1 CCP6M0 --00 0000
F70h CCPR7H Capture/Compare/PWM Register 7 High Byte xxxx xxxx
F6Fh CCPR7L Capture/Compare/PWM Register 7 Low Byte xxxx xxxx
F6Eh CCP7CON —— DC7B1 DC7B0 CCP7M3 CCP7M2 CCP7M1 CCP7M0 --00 0000
F6Dh TMR4 Timer4 Register xxxx xxxx
F6Ch PR4 Timer4 Period Register 1111 1111
F6Bh T4CON — T4OUTPS3 T4OUTPS2 T4OUTPS1 T4OUTPS0 TMR4ON T4CKPS1 T4CKPS0 -111 1111
F6Ah SSP2BUF MSSP Receive Buffer/Transmit Register xxxx xxxx
F69h SSP2ADD MSSP Address Register in I2C™ Slave Mode. MSSP1 Baud Rate Reload Register in I2C Master Mode. 0000 0000
F68h SSP2STAT SMP CKE D/A PSR/WUA BF 0000 0000
F67h SSP2CON1 WCOL SSPOV SSPEN CKP SSPM3 SSPM2 SSPM1 SSPM0 0000 0000
F66h SSP2CON2 GCEN ACKSTAT ACKDT ACKEN RCEN PEN RSEN SEN 0100 0000
F65h BAUDCON1 ABDOVF RCIDL RXDTP TXCKP BRG16 — WUE ABDEN 0100 0-00
F64h OSCCON2 — SOSCRUN ——SOSCGO— MFIOFS MFIOSEL -0-- 0-x0
F63h EEADRH EEPROM Address Register High Byte 0000 0000
F62h EEADR EEPROM Address Register Low Byte 0000 0000
F61h EEDATA EEPROM Data Register 0000 0000
F60h PIE6 — — —EEIE— CMP3IE CMP2IE CMP1IE ---0 -000
F5Fh RTCCFG RTCEN — RTCWREN RTCSYNC HALFSEC RTCOE RTCPTR1 RTCPTR0 0-00 0000
F5Eh RTCCAL CAL7 CAL6 CAL5 CAL4 CAL3 CAL2 CAL1 CAL0 0000 0000
F5Dh RTCVALH RTCC Value High Register Window Based on RTCPTR<1:0> xxxx xxxx
TABLE 6-2: PIC18F87K22 FAMILY REGISTER FILE SUMMARY (CONTINUED)
Address File Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Value on
POR, BOR
Note 1: The bit is available when Master Clear is disabled (MCLRE = 0). When MCLRE is set, the bit is unimplemented.
2: Unimplemented on 64-pin devices (PIC18F6XK22), read as ‘0’.
3: Unimplemented on devices with a program memory of 32 Kbytes (PIC18FX5K22).
PIC18F87K22 FAMILY
DS39960C-page 102 2011 Microchip Technology Inc.
F5Ch RTCVALL RTCC Value Low Register Window Based on RTCPTR<1:0> 0000 0000
F5Bh ALRMCFG ALRMEN CHIME AMASK3 AMASK2 AMASK1 AMASK0 ALRMPTR1 ALRMPTR0 0000 0000
F5Ah ALRMRPT ARPT7 ARPT6 ARPT5 ARPT4 ARPT3 ARPT2 ARPT1 ARPT0 0000 0000
F59h ALRMVALH Alarm Value High Register Window Based on APTR<1:0> xxxx xxxx
F58h ALRMVALL Alarm Value Low Register Window Based on APTR<1:0> xxxx xxxx
F57h CTMUCONH CTMUEN — CTMUSIDL TGEN EDGEN EDGSEQEN IDISSEN CTTRIG 0-00 0000
F56h CTMUCONL EDG2POL EDG2SEL1 EDG2SEL0 EDG1POL EDG1SEL1 EDG1SEL0 EDG2STAT EDG1STAT 0000 0000
F55h CTMUICONH ITRIM5 ITRIM4 ITRIM3 ITRIM2 ITRIM1 ITRIM0 IRNG1 IRNG0 0000 0000
F54h CM1CON CON COE CPOL EVPOL1 EVPOL0 CREF CCH1 CCH0 0001 1111
F53h PADCFG1 RDPU REPU RJPU(2) —— RTSECSEL1 RTSECSEL0 —000- -00-
F52h ECCP2AS ECCP2ASE ECCP2AS2 ECCP2AS1 ECCP2AS0 PSS2AC1 PSS2AC0 PSS2BD1 PSS2BD0 0000 0000
F51h ECCP2DEL P2RSEN P2DC6 P2DC5 P2DC4 P2DC3 P2DC2 P2DC1 P2DC0 0000 0000
F50h CCPR2H Capture/Compare/PWM Register 2 High Byte xxxx xxxx
F4Fh CCPR2L Capture/Compare/PWM Register 2 Low Byte xxxx xxxx
F4Eh CCP2CON P2M1 P2M0 DC2B1 DC2B0 CCP2M3 CCP2M2 CCP2M1 CCP2M0 0000 0000
F4Dh ECCP3AS ECCP3ASE ECCP3AS2 ECCP3AS1 ECCP3AS0 PSS3AC1 PSS3AC0 PSS3BD1 PSS3BD0 0000 0000
F4Ch ECCP3DEL P3RSEN P3DC6 P3DC5 P3DC4 P3DC3 P3DC2 P3DC1 P3DC0 0000 0000
F4Bh CCPR3H Capture/Compare/PWM Register 3 High Byte xxxx xxxx
F4Ah CCPR3L Capture/Compare/PWM Register 3 Low Byte xxxx xxxx
F49h CCP3CON P3M1 P3M0 DC3B1 DC3B0 CCP3M3 CCP3M2 CCP3M1 CCP3M0 0000 0000
F48h CCPR8H Capture/Compare/PWM Register 8 High Byte xxxx xxxx
F47h CCPR8L Capture/Compare/PWM Register 8 Low Byte xxxx xxxx
F46h CCP8CON —— DC8B1 DC8B0 CCP8M3 CCP8M2 CCP8M1 CCP8M0 --00 0000
F45h CCPR9H(3) Capture/Compare/PWM Register 9 High Byte xxxx xxxx
F44h CCPR9L(3) Capture/Compare/PWM Register 9 Low Byte xxxx xxxx
F43h CCP9CON(3) —— DC9B1 DC9B0 CCP9M3 CCP9M2 CCP9M1 CCP9M0 --00 0000
F42h CCPR10H(3) Capture/Compare/PWM Register 10 High Byte xxxx xxxx
F41h CCPR10L(3) Capture/Compare/PWM Register 10 Low Byte xxxx xxxx
F40h CCP10CON(3) —— DC10B1 DC10B0 CCP10M3 CCP10M2 CCP10M1 CCP10M0 --00 0000
F3Fh TMR7H(3) Timer7 Register High Byte xxxx xxxx
F3Eh TMR7L(3) Timer7 Register Low Byte 0000 0000
F3Dh T7CON(3) TMR7CS1 TMR7CS0 T7CKPS1 T7CKPS0 SOSCEN T7SYNC RD16 TMR7ON 0000 0000
F3Ch T7GCON(3) TMR7GE T7GPOL T7GTM T7GSPM T7GGO/
T7DONE
T7GVAL T7GSS1 T7GSS0 0000 0x00
F3Bh TMR6 Timer6 Register 0000 0000
F3Ah PR6 Timer6 Period Register 1111 1111
F39h T6CON — T6OUTPS3 T6OUTPS2 T6OUTPS1 T6OUTPS0 TMR6ON T6CKPS1 T6CKPS0 -000 0000
F38h TMR8 Timer8 Register 0000 0000
F37h PR8 Timer8 Period Register 1111 1111
F36h T8CON — T8OUTPS3 T8OUTPS2 T8OUTPS1 T8OUTPS0 TMR8ON T8CKPS1 T8CKPS0 -000 0000
F35h TMR1(3)0 TMR10 Register 0000 0000
F34h PR10(3) Timer10 Period Register 1111 1111
F33h T10CON(3) —
T10OUTPS3 T10OUTPS2 T10OUTPS1 T10OUTPS0 TMR10ON T10CKPS1 T10CKPS0
-000 0000
F32h TMR12(3) TMR12 Register 0000 0000
F31h PR12(3) Timer12 Period Register 1111 1111
F30h T12CON(3) —
T12OUTPS3 T12OUTPS2 T12OUTPS1 T12OUTPS0
TMR12ON T12CKPS1 T12CKPS0 -000 0000
F2Fh CM2CON CON COE CPOL EVPOL1 EVPOL0 CREF CCH1 CCH0 0001 1111
F2Eh CM3CON CON COE CPOL EVPOL1 EVPOL0 CREF CCH1 CCH0 0001 1111
F2Dh CCPTMRS0 C3TSEL1 C3TSEL0 C2TSEL2 C2TSEL1 C2TSEL0 C1TSEL2 C1TSEL1 C1TSEL0 0000 0000
TABLE 6-2: PIC18F87K22 FAMILY REGISTER FILE SUMMARY (CONTINUED)
Address File Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Value on
POR, BOR
Note 1: The bit is available when Master Clear is disabled (MCLRE = 0). When MCLRE is set, the bit is unimplemented.
2: Unimplemented on 64-pin devices (PIC18F6XK22), read as ‘0’.
3: Unimplemented on devices with a program memory of 32 Kbytes (PIC18FX5K22).
2011 Microchip Technology Inc. DS39960C-page 103
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F2Ch CCPTMRS1 C7TSEL1 C7TSEL0 — C6TSEL0 — C5TSEL0 C4TSEL1 C4TSEL0 00-0 -000
F2Bh CCPTMRS2 — — — C10TSEL0(3) — C9TSEL0(3) C8TSEL1 C8TSEL0 ---0 -000
F2Ah REFOCON ROON — ROSSLP ROSEL RODIV3 RODIV2 RODIV1 RODIV0 0-00 0000
F29h ODCON1 SSP1OD CCP2OD CCP1OD — — — — SSP2OD 000- ---0
F28h ODCON2 CCP10OD(3) CCP9OD(3) CCP8OD CCP7OD CCP6OD CCP5OD CCP4OD CCP3OD 0000 0000
F27h ODCON3 U2OD U1OD — — — — — CTMUDS 00-- ---0
F26h MEMCON(2) EBDIS —WAIT1WAIT0——WM1WM00-00 --00
F25h ANCON0 ANSEL7 ANSEL6 ANSEL5 ANSEL4 ANSEL3 ANSEL2 ANSEL1 ANSEL0 1111 1111
F24h ANCON1 ANSEL15 ANSEL14 ANSEL13 ANSEL12 ANSEL11 ANSEL10 ANSEL9 ANSEL8 1111 1111
F23h ANCON2 ANSEL23 ANSEL22 ANSEL21 ANSEL20 ANSEL19 ANSEL18 ANSEL17 ANSEL16 1111 1111
F22h RCSTA2 SPEN RX9 SREN CREN ADDEN FERR OERR RX9D 0000 000x
F21h TXSTA2 CSRC TX9 TXEN SYNC SENDB BRGH TRMT TX9D 0000 0010
F20h BAUDCON2 ABDOVF RCIDL RXDTP TXCKP BRG16 — WUE ABDEN 0100 0-00
F1Fh SPBRGH2 USART2 Baud Rate Generator High Byte 0000 0000
F1Eh SPBRG2 USART2 Baud Rate Generator 0000 0000
F1Dh RCREG2 Receive Data FIFO 0000 0000
F1Ch TXREG2 Transmit Data FIFO xxxx xxxx
F1Bh PSTR2CON CMPL1 CMPL0 — STRSYNC STRD STRC STRB STRA 00-0 0001
F1Ah PSTR3CON CMPL1 CMPL0 — STRSYNC STRD STRC STRB STRA 00-0 0001
F19h PMD0 CCP3MD CCP2MD CCP1MD UART2MD UART1MD SSP2MD SSP1MD ADCMD 0000 0000
F18h PMD1 PSPMD CTMUMD RTCCMD TMR4MD TMR3MD TMR2MD TMR1MD EMBMD 0000 0000
F17h PMD2 TMR10MD(3) TMR8MD TMR7MD(3) TMR6MD TMR5MD CMP3MD CMP2MD CMP1MD 0000 0000
F16h PMD3 CCP10MD(3) CCP9MD(3) CCP8MD CCP7MD CCP6MD CCP5MD CCP4MD TMR12MD(3) 0000 0000
TABLE 6-2: PIC18F87K22 FAMILY REGISTER FILE SUMMARY (CONTINUED)
Address File Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Value on
POR, BOR
Note 1: The bit is available when Master Clear is disabled (MCLRE = 0). When MCLRE is set, the bit is unimplemented.
2: Unimplemented on 64-pin devices (PIC18F6XK22), read as ‘0’.
3: Unimplemented on devices with a program memory of 32 Kbytes (PIC18FX5K22).
PIC18F87K22 FAMILY
DS39960C-page 104 2011 Microchip Technology Inc.
6.3.5 STATUS REGISTER
The STATUS register, shown in Register 6-2, contains
the arithmetic status of the ALU. The STATUS register
can be the operand for any instruction, as with any
other register. If the STATUS register is the destination
for an instruction that affects the Z, DC, C, OV or N bits,
the write to these five bits is disabled.
These bits are set or cleared according to the device
logic. Therefore, the result of an instruction with the
STATUS register as destination may be different than
intended. For example, CLRF STATUS will set the Z bit
but leave the other bits unchanged. The STATUS
register then reads back as ‘000u u1uu’.
It is recommended, therefore, that only BCF, BSF,
SWAPF, MOVFF and MOVWF instructions be used to
alter the STATUS register because these instructions
do not affect the Z, C, DC, OV or N bits in the STATUS
register.
For other instructions not affecting any Status bits, see
the instruction set summaries in Table 29-2 and
Table 29-3.
Note: The C and DC bits operate, in subtraction,
as borrow and digit borrow bits, respectively.
REGISTER 6-2: STATUS REGISTER
U-0 U-0 U-0 R/W-x R/W-x R/W-x R/W-x R/W-x
— — —NOVZDC
(1) C(2)
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7-5 Unimplemented: Read as ‘0’
bit 4 N: Negative bit
This bit is used for signed arithmetic (2’s complement). It indicates whether the result was negative
(ALU MSB = 1).
1 = Result was negative
0 = Result was positive
bit 3 OV: Overflow bit
This bit is used for signed arithmetic (2’s complement). It indicates an overflow of the seven-bit
magnitude which causes the sign bit (bit 7) to change state.
1 = Overflow occurred for signed arithmetic (in this arithmetic operation)
0 = No overflow occurred
bit 2 Z: Zero bit
1 = The result of an arithmetic or logic operation is zero
0 = The result of an arithmetic or logic operation is not zero
bit 1 DC: Digit Carry/Borrow bit(1)
For ADDWF, ADDLW, SUBLW and SUBWF instructions:
1 = A carry-out from the 4th low-order bit of the result occurred
0 = No carry-out from the 4th low-order bit of the result
bit 0 C: Carry/Borrow bit(2)
For ADDWF, ADDLW, SUBLW and SUBWF instructions:
1 = A carry-out from the Most Significant bit of the result occurred
0 = No carry-out from the Most Significant bit of the result occurred
Note 1: For borrow, the polarity is reversed. A subtraction is executed by adding the 2’s complement of the second
operand. For rotate (RRF, RLF) instructions, this bit is loaded with either bit 4 or bit 3 of the source register.
2: For borrow, the polarity is reversed. A subtraction is executed by adding the 2’s complement of the second
operand. For rotate (RRF, RLF) instructions, this bit is loaded with either the high or low-order bit of the
source register.
2011 Microchip Technology Inc. DS39960C-page 105
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6.4 Data Addressing Modes
While the program memory can be addressed in only
one way, through the program counter, information in
the data memory space can be addressed in several
ways. For most instructions, the addressing mode is
fixed. Other instructions may use up to three modes,
depending on which operands are used and whether or
not the extended instruction set is enabled.
The addressing modes are:
• Inherent
• Literal
•Direct
•Indirect
An additional addressing mode, Indexed Literal Offset,
is available when the extended instruction set is
enabled (XINST Configuration bit = 1). For details on
this mode’s operation, see Section 6.6.1 “Indexed
Addressing with Literal Offset”.
6.4.1 INHERENT AND LITERAL
ADDRESSING
Many PIC18 control instructions do not need any
argument at all. They either perform an operation that
globally affects the device or they operate implicitly on
one register. This addressing mode is known as Inherent
Addressing. Examples of this mode include SLEEP,
RESET and DAW.
Other instructions work in a similar way, but require an
additional explicit argument in the opcode. This method
is known as the Literal Addressing mode because the
instructions require some literal value as an argument.
Examples of this include ADDLW and MOVLW which,
respectively, add or move a literal value to the W
register. Other examples include CALL and GOTO,
which include a 20-bit program memory address.
6.4.2 DIRECT ADDRESSING
Direct Addressing specifies all or part of the source
and/or destination address of the operation within the
opcode itself. The options are specified by the
arguments accompanying the instruction.
In the core PIC18 instruction set, bit-oriented and
byte-oriented instructions use some version of Direct
Addressing by default. All of these instructions include
some 8-bit literal address as their Least Significant
Byte. This address specifies the instruction’s data
source as either a register address in one of the banks
of data RAM (see Section 6.3.3 “General Purpose
Register File”) or a location in the Access Bank (see
Section 6.3.2 “Access Bank”).
The Access RAM bit, ‘a’, determines how the address
is interpreted. When ‘a’ is ‘1’, the contents of the BSR
(Section 6.3.1 “Bank Sel ect Register” ) are used with
the address to determine the complete 12-bit address
of the register. When ‘a’ is ‘0’, the address is interpreted
as being a register in the Access Bank. Addressing that
uses the Access RAM is sometimes also known as
Direct Forced Addressing mode.
A few instructions, such as MOVFF, include the entire
12-bit address (either source or destination) in their
opcodes. In these cases, the BSR is ignored entirely.
The destination of the operation’s results is determined
by the destination bit, ‘d’. When ‘d’ is ‘1’, the results are
stored back in the source register, overwriting its origi-
nal contents. When ‘d’ is ‘0’, the results are stored in
the W register. Instructions without the ‘d’ argument
have a destination that is implicit in the instruction,
either the target register being operated on or the W
register.
6.4.3 INDIRECT ADDRESSING
Indirect Addressing allows the user to access a location
in data memory without giving a fixed address in the
instruction. This is done by using File Select Registers
(FSRs) as pointers to the locations to be read or written
to. Since the FSRs are themselves located in RAM as
Special Function Registers, they can also be directly
manipulated under program control. This makes FSRs
very useful in implementing data structures such as
tables and arrays in data memory.
The registers for Indirect Addressing are also
implemented with Indirect File Operands (INDFs) that
permit automatic manipulation of the pointer value with
auto-incrementing, auto-decrementing or offsetting
with another value. This allows for efficient code using
loops, such as the example of clearing an entire RAM
bank in Example 6-5. It also enables users to perform
Indexed Addressing and other Stack Pointer
operations for program memory in data memory.
EXAMPLE 6-5: HOW TO CLEAR RAM
(BANK 1) USING
INDIRECT ADDRESSING
Note: The execution of some instructions in the
core PIC18 instruction set are changed
when the PIC18 extended instruction set is
enabled. For more information, see
Section 6.6 “Data Memory and the
Extended Instruction Set”.
LFSR FSR0, 100h ;
NEXT CLRF POSTINC0 ; Clear INDF
; register then
; inc pointer
BTFSS FSR0H, 1 ; All done with
; Bank1?
BRA NEXT ; NO, clear next
CONTINUE ; YES, continue
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DS39960C-page 106 2011 Microchip Technology Inc.
6.4.3.1 FSR Registers and the
INDF Operand
At the core of Indirect Addressing are three sets of
registers: FSR0, FSR1 and FSR2. Each represents a
pair of 8-bit registers: FSRnH and FSRnL. The four
upper bits of the FSRnH register are not used, so each
FSR pair holds a 12-bit value. This represents a value
that can address the entire range of the data memory
in a linear fashion. The FSR register pairs, then, serve
as pointers to data memory locations.
Indirect Addressing is accomplished with a set of Indi-
rect File Operands, INDF0 through INDF2. These can
be thought of as “virtual” registers. The operands are
mapped in the SFR space, but are not physically imple-
mented. Reading or writing to a particular INDF register
actually accesses its corresponding FSR register pair.
A read from INDF1, for example, reads the data at the
address indicated by FSR1H:FSR1L.
Instructions that use the INDF registers as operands
actually use the contents of their corresponding FSR as
a pointer to the instruction’s target. The INDF operand
is just a convenient way of using the pointer.
Because Indirect Addressing uses a full 12-bit address,
data RAM banking is not necessary. Thus, the current
contents of the BSR and the Access RAM bit have no
effect on determining the target address.
FIGURE 6-8: INDIRECT ADDRES SING
FSR1H:FSR1L
0
7
Data Memory
000h
100h
200h
300h
F00h
E00h
FFFh
Bank 0
Bank 1
Bank 2
Bank 14
Bank 15
Bank 3
through
Bank 13
ADDWF, INDF1, 1
07
Using an instruction with one of the
Indirect Addressing registers as the
operand....
...uses the 12-bit address stored in
the FSR pair associated with that
register....
...to determine the data memory
location to be used in that operation.
In this case, the FSR1 pair contains
FCCh. This means the contents of
location FCCh will be added to that
of the W register and stored back in
FCCh.
xxxx1111 11001100
2011 Microchip Technology Inc. DS39960C-page 107
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6.4.3.2 FSR Registers and POSTINC,
POSTDEC, PREINC and PLUSW
In addition to the INDF operand, each FSR register pair
also has four additional indirect operands. Like INDF,
these are “virtual” registers that cannot be indirectly
read or written to. Accessing these registers actually
accesses the associated FSR register pair, but also
performs a specific action on its stored value.
These operands are:
• POSTDEC – Accesses the FSR value, then
automatically decrements it by ‘1’ afterwards
• POSTINC – Accesses the FSR value, then
automatically increments it by ‘1’ afterwards
• PREINC – Increments the FSR value by ‘1’, then
uses it in the operation
• PLUSW – Adds the signed value of the W register
(range of -127 to 128) to that of the FSR and uses
the new value in the operation
In this context, accessing an INDF register uses the
value in the FSR registers without changing them.
Similarly, accessing a PLUSW register gives the FSR
value, offset by the value in the W register, with neither
value actually changed in the operation. Accessing the
other virtual registers changes the value of the FSR
registers.
Operations on the FSRs with POSTDEC, POSTINC
and PREINC affect the entire register pair. Rollovers of
the FSRnL register, from FFh to 00h, carry over to the
FSRnH register. On the other hand, results of these
operations do not change the value of any flags in the
STATUS register (for example, Z, N and OV bits).
The PLUSW register can be used to implement a form
of Indexed Addressing in the data memory space. By
manipulating the value in the W register, users can
reach addresses that are fixed offsets from pointer
addresses. In some applications, this can be used to
implement some powerful program control structure,
such as software stacks, inside of data memory.
6.4.3.3 Operations by FSRs on FSRs
Indirect Addressing operations that target other FSRs
or virtual registers represent special cases. For
example, using an FSR to point to one of the virtual
registers will not result in successful operations.
As a specific case, assume that the FSR0H:FSR0L
registers contain FE7h, the address of INDF1.
Attempts to read the value of the INDF1, using INDF0
as an operand, will return 00h. Attempts to write to
INDF1, using INDF0 as the operand, will result in a
NOP.
On the other hand, using the virtual registers to write to
an FSR pair may not occur as planned. In these cases,
the value will be written to the FSR pair, but without any
incrementing or decrementing. Thus, writing to INDF2
or POSTDEC2 will write the same value to the
FSR2H:FSR2L.
Since the FSRs are physical registers mapped in the
SFR space, they can be manipulated through all direct
operations. Users should proceed cautiously when
working on these registers, however, particularly if their
code uses Indirect Addressing.
Similarly, operations by Indirect Addressing are gener-
ally permitted on all other SFRs. Users should exercise
the appropriate caution, so that they do not inadvertently
change settings that might affect the operation of the
device.
6.5 Program Memory and the
Extended Instruct ion Set
The operation of program memory is unaffected by the
use of the extended instruction set.
Enabling the extended instruction set adds five
additional two-word commands to the existing PIC18
instruction set: ADDFSR, CALLW, MOVSF, MOVSS and
SUBFSR. These instructions are executed as described
in Section 6.2.4 “Two-Word Instructions”.
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DS39960C-page 108 2011 Microchip Technology Inc.
6.6 Data Memory and the Extended
Instruction Set
Enabling the PIC18 extended instruction set (XINST
Configuration bit = 1) significantly changes certain
aspects of data memory and its addressing. Using the
Access Bank for many of the core PIC18 instructions
introduces a new addressing mode for the data memory
space. This mode also alters the behavior of Indirect
Addressing using FSR2 and its associated operands.
What does not change is just as important. The size of
the data memory space is unchanged, as well as its
linear addressing. The SFR map remains the same.
Core PIC18 instructions can still operate in both Direct
and Indirect Addressing mode. Inherent and literal
instructions do not change at all. Indirect Addressing
with FSR0 and FSR1 also remains unchanged.
6.6.1 INDEXED ADDRESSING WITH
LITERAL OFFSET
Enabling the PIC18 extended instruction set changes
the behavior of Indirect Addressing using the FSR2
register pair and its associated file operands. Under the
proper conditions, instructions that use the Access
Bank – that is, most bit-oriented and byte-oriented
instructions – can invoke a form of Indexed Addressing
using an offset specified in the instruction. This special
addressing mode is known as Indexed Addressing with
Literal Offset or the Indexed Literal Offset mode.
When using the extended instruction set, this
addressing mode requires the following:
• Use of the Access Bank (‘a’ = 0)
• A file address argument that is less than or equal
to 5Fh
Under these conditions, the file address of the
instruction is not interpreted as the lower byte of an
address (used with the BSR in Direct Addressing) or as
an 8-bit address in the Access Bank. Instead, the value
is interpreted as an offset value to an Address Pointer
specified by FSR2. The offset and the contents of FSR2
are added to obtain the target address of the operation.
6.6.2 INSTRUCTIONS AFFECTED BY
INDEXED LITERAL OFFSET MODE
Any of the core PIC18 instructions that can use Direct
Addressing are potentially affected by the Indexed
Literal Offset Addressing mode. This includes all
byte-oriented and bit-oriented instructions, or almost
one-half of the standard PIC18 instruction set. Instruc-
tions that only use Inherent or Literal Addressing
modes are unaffected.
Additionally, byte-oriented and bit-oriented instructions
are not affected if they do not use the Access Bank
(Access RAM bit = 1), or include a file address of 60h
or above. Instructions meeting these criteria will
continue to execute as before. A comparison of the
different possible addressing modes when the
extended instruction set is enabled is shown in
Figure 6-9.
Those who desire to use byte-oriented or bit-oriented
instructions in the Indexed Literal Offset mode should
note the changes to assembler syntax for this mode.
This is described in more detail in Section 29.2.1
“Extended Instruction Syntax”.
2011 Microchip Technology Inc. DS39960C-page 109
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FIGURE 6-9: COMPARING ADDRESSING OPTIONS FOR BIT-ORIENTED AND
BYTE-ORIENTED INSTRUCTIONS (EXTENDED INSTRUCTION SET ENABLED)
EXAMPLE INSTRUCTION: ADDWF, f, d, a (Opcode: 0010 01da ffff ffff)
When a = 0 and f 60h:
The instruction executes in
Direct Forced mode. ‘f’ is
interpreted as a location in the
Access RAM between 060h
and FFFh. This is the same as
locations, F60h to FFFh
(Bank 15), of data memory.
Locations below 060h are not
available in this addressing
mode.
When a = 0 and f5Fh:
The instruction executes in
Indexed Literal Offset mode. ‘f’
is interpreted as an offset to the
address value in FSR2. The
two are added together to
obtain the address of the target
register for the instruction. The
address can be anywhere in
the data memory space.
Note that in this mode, the
correct syntax is now:
ADDWF [k], d
where ‘k’ is the same as ‘f’.
When a = 1 (all values of f):
The instruction executes in
Direct mode (also known as
Direct Long mode). ‘f’ is
interpreted as a location in
one of the 16 banks of the data
memory space. The bank is
designated by the Bank Select
Register (BSR). The address
can be in any implemented
bank in the data memory
space.
000h
060h
100h
F00h
F40h
FFFh
Valid range
00h
60h
FFh
Data Memory
Acce ss RA M
Bank 0
Bank 1
through
Bank 14
Bank 15
SFRs
000h
060h
100h
F00h
F40h
FFFh Data M emory
Bank 0
Bank 1
through
Bank 14
Bank 15
SFRs
FSR2H FSR2L
ffffffff001001da
ffffffff001001da
000h
060h
100h
F00h
F40h
FFFh Data M emory
Bank 0
Bank 1
through
Bank 14
Bank 15
SFRs
for ‘f’
BSR
00000000
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6.6.3 MAPPING THE ACCESS BANK IN
INDEXED LITERAL OFFSET MODE
The use of Indexed Literal Offset Addressing mode
effectively changes how the lower part of Access RAM
(00h to 5Fh) is mapped. Rather than containing just the
contents of the bottom part of Bank 0, this mode maps
the contents from Bank 0 and a user-defined “window”
that can be located anywhere in the data memory
space.
The value of FSR2 establishes the lower boundary of
the addresses mapped into the window, while the
upper boundary is defined by FSR2 plus 95 (5Fh).
Addresses in the Access RAM above 5Fh are mapped
as previously described. (See Section 6.3.2 “Access
Bank”.) An example of Access Bank remapping in this
addressing mode is shown in Figure 6-10.
Remapping the Access Bank applies only to operations
using the Indexed Literal Offset mode. Operations that
use the BSR (Access RAM bit = 1) will continue to use
Direct Addressing as before. Any Indirect or Indexed
Addressing operation that explicitly uses any of the
indirect file operands (including FSR2) will continue to
operate as standard Indirect Addressing. Any instruc-
tion that uses the Access Bank, but includes a register
address of greater than 05Fh, will use Direct
Addressing and the normal Access Bank map.
6.6.4 BSR IN INDEXED LITERAL
OFFSET MODE
Although the Access Bank is remapped when the
extended instruction set is enabled, the operation of the
BSR remains unchanged. Direct Addressing, using the
BSR to select the data memory bank, operates in the
same manner as previously described.
FIGURE 6-10: REMAPPING THE ACCESS BANK WITH INDEXED LITERAL
OFFSET ADDRESSING
Data Memory
000h
100h
200h
F60h
F00h
FFFh
Bank 1
Bank 15
Bank 2
through
Bank 14
SFRs
05Fh
ADDWF f, d, a
FSR2H:FSR2L = 120h
Locations in the region
from the FSR2 Pointer
(120h) to the pointer plus
05Fh (17Fh) are mapped
to the bottom of the
Access RAM (000h-05Fh).
Special Function Registers
at F60h through FFFh are
mapped to 60h through
FFh, as usual.
Bank 0 addresses below
5Fh are not available in
this mode. They can still
be addressed by using the
BSR.
Access Bank
00h
FFh
Bank 0
SFRs
Bank 1 “Wi ndow”
Not Accessible
Window
Example Situation:
120h
17Fh
5Fh
60h
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7.0 FLASH PROGRAM MEMORY
The Flash program memory is readable, writable and
erasable during normal operation over the entire VDD
range.
A read from program memory is executed on one byte
at a time. For execution of a write to or erasure of
program memory:
• Memory of 32 Kbytes and 64 Kbytes
(PIC18FX5K22 and PIC18FX6K22 devices) –
Blocks of 64 bytes
• Memory of 128 Kbytes (PIC18FX7K22 devices) –
Blocks of 128 bytes
Writing or erasing program memory will cease
instruction fetches until the operation is complete. The
program memory cannot be accessed during the write
or erase, therefore, code cannot execute. An internal
programming timer terminates program memory writes
and erases.
A value written to program memory does not need to be
a valid instruction. Executing a program memory
location that forms an invalid instruction results in a
NOP.
7.1 Table Reads and Table Writes
In order to read and write program memory, there are
two operations that allow the processor to move bytes
between the program memory space and the data RAM:
• Table Read (TBLRD)
• Table Write (TBLWT)
The program memory space is 16 bits wide, while the
data RAM space is 8 bits wide. Table reads and table
writes move data between these two memory spaces
through an 8-bit register (TABLAT).
Table read operations retrieve data from program
memory and place it into the data RAM space.
Figure 7-1 shows the operation of a table read with
program memory and data RAM.
Table write operations store data from the data memory
space into holding registers in program memory. The
procedure to write the contents of the holding registers
into program memory is detailed in Section 7.5 “Writin g
to Flash Program Memory”. Figure 7-2 shows the
operation of a table write with program memory and data
RAM.
Table operations work with byte entities. A table block
containing data, rather than program instructions, is not
required to be word-aligned. Therefore, a table block can
start and end at any byte address. If a table write is being
used to write executable code into program memory,
program instructions will need to be word-aligned.
FIGURE 7-1: TABLE READ OPERATION
Table Pointer(1)
Table Latch (8-bit)
Program Memory
TBLPTRH TBLPTRL
TABLAT
TBLPTRU
Instruction: TBLRD*
Note 1: Table Pointer register points to a byte in program memory.
Program Memory
(TBLPTR)
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FIGURE 7-2: TABLE WRITE OPERATION
7.2 Control Registers
Several control registers are used in conjunction with
the TBLRD and TBLWT instructions. These include the:
• EECON1 register
• EECON2 register
• TABLAT register
• TBLPTR registers
7.2.1 EECON1 AND EECON2 REGISTERS
The EECON1 register (Register 7-1) is the control
register for memory accesses. The EECON2 register,
not a physical register, is used exclusively in the
memory write and erase sequences. Reading
EECON2 will read all ‘0’s.
The EEPGD control bit determines if the access is a
program or data EEPROM memory access. When
clear, any subsequent operations operate on the data
EEPROM memory. When set, any subsequent
operations operate on the program memory.
The CFGS control bit determines if the access is to the
Configuration/Calibration registers or to program
memory/data EEPROM memory. When set,
subsequent operations operate on Configuration
registers regardless of EEPGD (see Section 28.0
“Spe cial Features o f the CPU”). When clear, memory
selection access is determined by EEPGD.
The FREE bit, when set, allows a program memory
erase operation. When FREE is set, the erase
operation is initiated on the next WR command. When
FREE is clear, only writes are enabled.
The WREN bit, when set, allows a write operation. On
power-up, the WREN bit is clear. The WRERR bit is set
in hardware when the WR bit is set and cleared when
the internal programming timer expires and the write
operation is complete.
The WR control bit initiates write operations. The bit
cannot be cleared, only set, in software. It is cleared in
hardware at the completion of the write operation.
Table Pointer(1) Table Latch (8-bit)
TBLPTRH TBLPTRL TABLAT
Program Memory
(TBLPTR)
TBLPTRU
Instruction: TBLWT*
Note 1: The Table Pointer actually points to one of 64 holding registers; the address of which is determined by
TBLPTRL<5:0>. The process for physically writing data to the program memory array is discussed in
Sect ion 7.5 “Writing t o Fla s h Program Memory”.
Holding Registers
Program Memory
Note: During normal operation, the WRERR is
read as ‘1’. This can indicate that a write
operation was prematurely terminated by
a Reset or a write operation was
attempted improperly.
Note: The EEIF interrupt flag bit (PIR6<4>) is
set when the write is complete. It must be
cleared in software.
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REGISTER 7-1: EECON1: EEPROM CONTROL REGISTER 1
R/W-x R/W-x U-0 R/W-0 R/W-x R/W-0 R/S-0 R/S-0
EEPGD CFGS — FREE WRERR(1) WREN WR RD
bit 7 bit 0
Legend: S = Settable bit
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 EEPGD: Flash Program or Data EEPROM Memory Select bit
1 = Access Flash program memory
0 = Access data EEPROM memory
bit 6 CFGS: Flash Program/Data EEPROM or Configuration Select bit
1 = Access Configuration registers
0 = Access Flash program or data EEPROM memory
bit 5 Unimplemented: Read as ‘0’
bit 4 FREE: Flash Row Erase Enable bit
1 = Erase the program memory row addressed by TBLPTR on the next WR command
(cleared by completion of erase operation)
0 = Perform write-only
bit 3 WRERR: Flash Program/Data EEPROM Error Flag bit(1)
1 = A write operation is prematurely terminated (any Reset during self-timed programming in normal
operation or an improper write attempt)
0 = The write operation completed
bit 2 WREN: Flash Program/Data EEPROM Write Enable bit
1 = Allows write cycles to Flash program/data EEPROM
0 = Inhibits write cycles to Flash program/data EEPROM
bit 1 WR: Write Control bit
1 = Initiates a data EEPROM erase/write cycle or a program memory erase cycle or write cycle.
(The operation is self-timed and the bit is cleared by hardware once the write is complete.
The WR bit can only be set (not cleared) in software.)
0 = Write cycle to the EEPROM is complete
bit 0 RD: Read Control bit
1 = Initiates an EEPROM read (Read takes one cycle. RD is cleared in hardware. The RD bit can only
be set (not cleared) in software. The RD bit cannot be set when EEPGD = 1 or CFGS = 1.)
0 = Does not initiate an EEPROM read
Note 1: When a WRERR occurs, the EEPGD and CFGS bits are not cleared. This allows tracing of the error
condition.
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DS39960C-page 114 2011 Microchip Technology Inc.
7.2.2 TABLAT – TABLE LATCH REGISTER
The Table Latch (TABLAT) is an eight-bit register
mapped into the SFR space. The Table Latch register
is used to hold 8-bit data during data transfers between
program memory and data RAM.
7.2.3 TBLPTR – TABLE POINTER
REGISTER
The Table Pointer (TBLPTR) register addresses a byte
within the program memory. The TBLPTR is comprised
of three SFR registers: Table Pointer Upper Byte, Table
Pointer High Byte and Table Pointer Low Byte
(TBLPTRU:TBLPTRH:TBLPTRL). These three regis-
ters join to form a 22-bit wide pointer. The low-order
21 bits allow the device to address up to 2 Mbytes of
program memory space. The 22nd bit allows access to
the Device ID, the User ID and the Configuration bits.
The Table Pointer register, TBLPTR, is used by the
TBLRD and TBLWT instructions. These instructions can
update the TBLPTR in one of four ways, based on the
table operation. These operations are shown in
Table 7-1 and only affect the low-order 21 bits.
7.2.4 TABLE POINTER BOUNDARIES
TBLPTR is used in reads, writes and erases of the
Flash program memory.
When a TBLRD is executed, all 22 bits of the TBLPTR
determine which byte is read from program memory
into TABLAT.
When a TBLWT is executed, the six LSbs of the Table
Pointer register (TBLPTR<5:0>) determine which of
the 64 program memory holding registers is written to.
When the timed write to program memory begins (via
the WR bit), the 16 MSbs of the TBLPTR
(TBLPTR<21:6>) determine which program memory
block of 64 bytes is written to. For more detail, see
Section 7.5 “Writing to Flash Program Memory”.
When an erase of program memory is executed, the
16 MSbs of the Table Pointer register (TBLPTR<21:6>)
point to the 64-byte block that will be erased. The Least
Significant bits (TBLPTR<5:0>) are ignored.
Figure 7-3 describes the relevant boundaries of the
TBLPTR based on Flash program memory operations.
TABLE 7-1: TABLE POINTER OPERATIONS WITH TBLRD AND TBLWT INSTRUCTIONS
FIGURE 7-3: TABLE POINTER BOUNDARIES BASED ON OPERATION
Example Operation on Table Pointer
TBLRD*
TBLWT* TBLPTR is not modified
TBLRD*+
TBLWT*+ TBLPTR is incremented after the read/write
TBLRD*-
TBLWT*- TBLPTR is decremented after the read/write
TBLRD+*
TBLWT+* TBLPTR is incremented before the read/write
21 16 15 87 0
TABLE ERASE/WRITE TABLE WRITE
TABLE READ – TBLPTR<21:0>
TBLPTRLTBLPTRH
TBLPTRU
TBLPTR<5:0>TBLPTR<21:6>
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7.3 Reading the Flash Program
Memory
The TBLRD instruction is used to retrieve data from
program memory and places it into data RAM. Table
reads from program memory are performed one byte at
a time.
TBLPTR points to a byte address in program space.
Executing TBLRD places the byte pointed to into
TABLAT. In addition, the TBLPTR can be modified
automatically for the next table read operation.
The internal program memory is typically organized by
words. The Least Significant bit of the address selects
between the high and low bytes of the word. Figure 7-4
shows the interface between the internal program
memory and the TABLAT.
FIGURE 7-4: READ S FROM FLASH PROGRAM MEMORY
EXAMPLE 7-1: READING A FLASH PROGRAM MEMORY WORD
(Even Byte Address)
Program Memory
(Odd Byte Address)
TBLRD TABLAT
TBLPTR = xxxxx1
FETCH
Instruction Register
(IR) Read Register
TBLPTR = xxxxx0
MOVLW CODE_ADDR_UPPER ; Load TBLPTR with the base
MOVWF TBLPTRU ; address of the word
MOVLW CODE_ADDR_HIGH
MOVWF TBLPTRH
MOVLW CODE_ADDR_LOW
MOVWF TBLPTRL
READ_WORD TBLRD*+ ; read into TABLAT and increment
MOVF TABLAT, W ; get data
MOVWF WORD_EVEN
TBLRD*+ ; read into TABLAT and increment
MOVF TABLAT, W ; get data
MOVF WORD_ODD
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7.4 Erasing Flash Program Memory
The erase blocks are:
• PIC18FX5K22 and PIC18FX6K22 – 32 words or
64 bytes
• PIC18FX7K22 – 64 words or 128 bytes
Word erase in the Flash array is not supported.
When initiating an erase sequence from the micro-
controller itself, a block of 64 or 128 bytes of program
memory is erased. The Most Significant 16 bits of the
TBLPTR<21:6> point to the block being erased. The
TBLPTR<5:0> bits are ignored.
The EECON1 register commands the erase operation.
The EEPGD bit must be set to point to the Flash
program memory. The WREN bit must be set to enable
write operations. The FREE bit is set to select an erase
operation.
For protection, the write initiate sequence for EECON2
must be used.
A long write is necessary for erasing the internal Flash.
Instruction execution is halted while in a long write
cycle. The long write will be terminated by the internal
programming timer.
7.4.1 FLASH PROGRAM MEMORY
ERASE SEQUENCE
The sequence of events for erasing a block of internal
program memory location is:
1. Load the Table Pointer register with the address
of row to be erased.
2. Set the EECON1 register for the erase operation:
• Set the EEPGD bit to point to program memory
• Clear the CFGS bit to access program memory
• Set the WREN bit to enable writes
• Set the FREE bit to enable the erase
3. Disable the interrupts.
4. Write 0x55 to EECON2.
5. Write 0xAA to EECON2.
6. Set the WR bit.
This begins the row erase cycle.
The CPU will stall for the duration of the erase
for TIW. (See Parameter D133A.)
7. Re-enable interrupts.
EXAMPLE 7-2: ERASING A FLASH PROGRAM MEMORY ROW
MOVLW CODE_ADDR_UPPER ; load TBLPTR with the base
MOVWF TBLPTRU ; address of the memory block
MOVLW CODE_ADDR_HIGH
MOVWF TBLPTRH
MOVLW CODE_ADDR_LOW
MOVWF TBLPTRL
ERASE_ROW BSF EECON1, EEPGD ; point to Flash program memory
BCF EECON1, CFGS ; access Flash program memory
BSF EECON1, WREN ; enable write to memory
BSF EECON1, FREE ; enable Row Erase operation
BCF INTCON, GIE ; disable interrupts
Required MOVLW 0x55
Sequence MOVWF EECON2 ; write 55h
MOVLW 0xAA
MOVWF EECON2 ; write 0AAh
BSF EECON1, WR ; start erase (CPU stall)
BSF INTCON, GIE ; re-enable interrupts
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7.5 Writing to Flash Program Memory
The programming blocks are:
• PIC18FX5K22 and PIC18FX6K22 – 32 words or
64 bytes
• PIC18FX7K22 – 64 words or 128 bytes
Word or byte programming is not supported.
Table writes are used internally to load the holding
registers needed to program the Flash memory. The
number of holding registers used for programming by
the table writes are:
• PIC18FX5K22 and PIC18FX6K22 – 64
• PIC18FX7K22 – 128
Since the Table Latch (TABLAT) is only a single byte, the
TBLWT instruction may need to be executed 64 times for
each programming operation. All of the table write oper-
ations will essentially be short writes because only the
holding registers are written. At the end of updating the
64 or 128 holding registers, the EECON1 register must
be written to in order to start the programming operation
with a long write.
The long write is necessary for programming the
internal Flash. Instruction execution is halted while in a
long write cycle. The long write is terminated by the
internal programming timer.
The EEPROM on-chip timer controls the write time.
The write/erase voltages are generated by an on-chip
charge pump, rated to operate over the voltage range
of the device.
FIGURE 7-5: TABLE WRITES TO FLASH PROGRAM MEMORY
Note: The default value of the holding registers
on device Resets and after write opera-
tions is FFh. A write of FFh to a holding
register does not modify that byte. This
means that individual bytes of program
memory may be modified, provided that
the change does not attempt to change
any bit from a ‘0’ to a ‘1’. When modifying
individual bytes, it is not necessary to load
all 64 or 128 holding registers before
executing a write operation.
TABLAT
TBLPTR = xxxx3FTBLPTR = xxxxx1TBLPTR = xxxxx0
Write Register
TBLPTR = xxxxx2
Program Memory
Holding Register Holding Register Holding Register Holding Register
88 8 8
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7.5.1 FLASH PROGRAM MEMORY WRITE
SEQUENCE
The sequence of events for programming an internal
program memory location should be:
1. Read the 64 or 128 bytes into RAM.
2. Update the data values in RAM as necessary.
3. Load the Table Pointer register with the address
being erased.
4. Execute the row erase procedure.
5. Load the Table Pointer register with the address
of the first byte being written.
6. Write the 64 or 128 bytes into the holding
registers with auto-increment.
7. Set the EECON1 register for the write operation:
• Set the EEPGD bit to point to program memory
• Clear the CFGS bit to access program memory
• Set the WREN to enable byte writes
8. Disable the interrupts.
9. Write 0x55 to EECON2.
10. Write 0xAA to EECON2.
11. Set the WR bit. This will begin the write cycle.
The CPU will stall for duration of the write for TIW
(see Parameter D133A).
12. Re-enable the interrupts.
13. Verify the memory (table read).
An example of the required code is shown in
Example 7-3 on the following page 119.
Note: Before setting the WR bit, the Table
Pointer address needs to be within the
intended address range of the 64 or
128 bytes in the holding register.
Note: Self-write execution to Flash and
EEPROM memory cannot be done while
running in LP Oscillator mode (Low-Power
mode). Therefore, executing a self-write
will put the device into High-Power mode.
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EXAMPLE 7-3: WRITING TO FLASH PROGRAM MEMORY
MOVLW SIZE_OF_BLOCK ; number of bytes in erase block
MOVWF COUNTER
MOVLW BUFFER_ADDR_HIGH ; point to buffer
MOVWF FSR0H
MOVLW BUFFER_ADDR_LOW
MOVWF FSR0L
MOVLW CODE_ADDR_UPPER ; Load TBLPTR with the base
MOVWF TBLPTRU ; address of the memory block
MOVLW CODE_ADDR_HIGH
MOVWF TBLPTRH
MOVLW CODE_ADDR_LOW
MOVWF TBLPTRL
READ_BLOCK TBLRD*+ ; read into TABLAT, and inc
MOVF TABLAT, W ; get data
MOVWF POSTINC0 ; store data
DECFSZ COUNTER ; done?
BRA READ_BLOCK ; repeat
MODIFY_WORD MOVLW DATA_ADDR_HIGH ; point to buffer
MOVWF FSR0H
MOVLW DATA_ADDR_LOW
MOVWF FSR0L
MOVLW NEW_DATA_LOW ; update buffer word
MOVWF POSTINC0
MOVLW NEW_DATA_HIGH
MOVWF INDF0
ERASE_BLOCK MOVLW CODE_ADDR_UPPER ; load TBLPTR with the base
MOVWF TBLPTRU ; address of the memory block
MOVLW CODE_ADDR_HIGH
MOVWF TBLPTRH
MOVLW CODE_ADDR_LOW
MOVWF TBLPTRL
BSF EECON1, EEPGD ; point to Flash program memory
BCF EECON1, CFGS ; access Flash program memory
BSF EECON1, WREN ; enable write to memory
BSF EECON1, FREE ; enable Row Erase operation
BCF INTCON, GIE ; disable interrupts
MOVLW 0x55
Required MOVWF EECON2 ; write 55h
Sequence MOVLW 0xAA
MOVWF EECON2 ; write 0AAh
BSF EECON1, WR ; start erase (CPU stall)
BSF INTCON, GIE ; re-enable interrupts
TBLRD*- ; dummy read decrement
MOVLW BUFFER_ADDR_HIGH ; point to buffer
MOVWF FSR0H
MOVLW BUFFER_ADDR_LOW
MOVWF FSR0L
WRITE_BUFFER_BACK
MOVLW SIZE_OF_BLOCK ; number of bytes in holding register
MOVWF COUNTER
WRITE_BYTE_TO_HREGS
MOVFF POSTINC0, WREG ; get low byte of buffer data
MOVWF TABLAT ; present data to table latch
TBLWT+* ; write data, perform a short write
; to internal TBLWT holding register.
DECFSZ COUNTER ; loop until buffers are full
BRA WRITE_BYTE_TO_HREGS
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EXAMPLE 7-3: WRITING TO FLASH PROGRAM MEMORY (CONTINUED)
7.5.2 WRITE VERIFY
Depending on the application, good programming
practice may dictate that the value written to the
memory should be verified against the original value.
This should be used in applications where excessive
writes can stress bits near the specification limit.
7.5.3 UNEXPECTED TERMINATION OF
WRITE OPERATION
If a write is terminated by an unplanned event, such as
loss of power or an unexpected Reset, the memory
location just programmed should be verified and repro-
grammed if needed. If the write operation is interrupted
by a MCLR Reset or a WDT Time-out Reset during
normal operation, the user can check the WRERR bit
and rewrite the location(s) as needed.
7.5.4 PROTECTION AGAINST
SPURIOUS WRITES
To protect against spurious writes to Flash program
memory, the write initiate sequence must also be
followed. See Section 28.0 “Special Features of the
CPU” for more detail.
7.6 Flash Program Operation During
Code Protection
See Section 28.6 “Program Verification and Code
Protection” for details on code protection of Flash
program memory.
TABLE 7-2: REGISTERS ASSOCIATED WITH PROGRAM FLASH MEMORY
PROGRAM_MEMORY BSF EECON1, EEPGD ; point to Flash program memory
BCF EECON1, CFGS ; access Flash program memory
BSF EECON1, WREN ; enable write to memory
BCF INTCON, GIE ; disable interrupts
MOVLW 0x55
Required MOVWF EECON2 ; write 55h
Sequence MOVLW 0xAA
MOVWF EECON2 ; write 0AAh
BSF EECON1, WR ; start program (CPU stall)
BSF INTCON, GIE ; re-enable interrupts
BCF EECON1, WREN ; disable write to memory
Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
TBLPTRU ——bit 21
(1) Program Memory Table Pointer Upper Byte (TBLPTR<20:16>)
TBPLTRH Program Memory Table Pointer High Byte (TBLPTR<15:8>)
TBLPTRL Program Memory Table Pointer Low Byte (TBLPTR<7:0>)
TABLAT Program Memory Table Latch
INTCON GIE/GIEH PEIE/GIEL TMR0IE INT0IE RBIE TMR0IF INT0IF RBIF
EECON2 EEPROM Control Register 2 (not a physical register)
EECON1 EEPGD CFGS — FREE WRERR WREN WR RD
IPR6 — — — EEIP —CMP3IP CMP2IP CMP1IP
PIR6 — — — EEIF — CMP3IF CMP2IF CMP1IF
PIE6 — — — EEIE —CMP3IE CMP2IE CMP1IE
Legend: — = unimplemented, read as ‘0’. Shaded cells are not used during Flash/EEPROM access.
Note 1: Bit 21 of the TBLPTRU allows access to the device Configuration bits.
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8.0 EXTERNAL ME MORY BUS
The External Memory Bus (EMB) allows the device to
access external memory devices (such as Flash,
EPROM or SRAM) as program or data memory. It
supports both 8 and 16-Bit Data Width modes and
three address widths of up to 20 bits.
The bus is implemented with 28 pins, multiplexed
across four I/O ports. Three ports (PORTD, PORTE
and PORTH) are multiplexed with the address/data bus
for a total of 20 available lines, while PORTJ is
multiplexed with the bus control signals.
A list of the pins and their functions is provided in
Table 8-1.
TABLE 8-1: PIC18F87K22 FAMILY EXTERNAL BUS – I/O PORT FUNCTIONS
Note: The external memory bus is not
implemented on 64-pin devices.
Name Port Bit External Memory Bus Function
RD0/AD0 PORTD 0 Address bit 0 or Data bit 0
RD1/AD1 PORTD 1 Address bit 1 or Data bit 1
RD2/AD2 PORTD 2 Address bit 2 or Data bit 2
RD3/AD3 PORTD 3 Address bit 3 or Data bit 3
RD4/AD4 PORTD 4 Address bit 4 or Data bit 4
RD5/AD5 PORTD 5 Address bit 5 or Data bit 5
RD6/AD6 PORTD 6 Address bit 6 or Data bit 6
RD7/AD7 PORTD 7 Address bit 7 or Data bit 7
RE0/AD8 PORTE 0 Address bit 8 or Data bit 8
RE1/AD9 PORTE 1 Address bit 9 or Data bit 9
RE2/AD10 PORTE 2 Address bit 10 or Data bit 10
RE3/AD11 PORTE 3 Address bit 11 or Data bit 11
RE4/AD12 PORTE 4 Address bit 12 or Data bit 12
RE5/AD13 PORTE 5 Address bit 13 or Data bit 13
RE6/AD14 PORTE 6 Address bit 14 or Data bit 14
RE7/AD15 PORTE 7 Address bit 15 or Data bit 15
RH0/A16 PORTH 0 Address bit 16
RH1/A17 PORTH 1 Address bit 17
RH2/A18 PORTH 2 Address bit 18
RH3/A19 PORTH 3 Address bit 19
RJ0/ALE PORTJ 0 Address Latch Enable (ALE) Control pin
RJ1/OE PORTJ 1 Output Enable (OE) Control pin
RJ2/WRL PORTJ 2 Write Low (WRL) Control pin
RJ3/WRH PORTJ 3 Write High (WRH) Control pin
RJ4/BA0 PORTJ 4 Byte Address bit 0 (BA0)
RJ5/CE PORTJ 5 Chip Enable (CE) Control pin
RJ6/LB PORTJ 6 Lower Byte Enable (LB) Control pin
RJ7/UB PORTJ 7 Upper Byte Enable (UB) Control pin
Note: For the sake of clarity, only I/O port and external bus assignments are shown here. One or more additional
multiplexed features may be available on some pins.
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DS39960C-page 122 2011 Microchip Technology Inc.
8.1 External Memory Bus Control
The operation of the interface is controlled by the
MEMCON register (Register 8-1). This register is
available in all program memory operating modes
except Microcontroller mode. In this mode, the register
is disabled and cannot be written to.
The EBDIS bit (MEMCON<7>) controls the operation
of the bus and related port functions. Clearing EBDIS
enables the interface and disables the I/O functions of
the ports, as well as any other functions multiplexed to
those pins. Setting the bit enables the I/O ports and
other functions, but allows the interface to override
everything else on the pins when an external memory
operation is required. By default, the external bus is
always enabled and disables all other I/O.
The operation of the EBDIS bit is also influenced by the
program memory mode being used. This is discussed
in more detail in Section 8.5 “Program Memory
Modes and the External Memory Bus”.
The WAIT bits allow for the addition of Wait states to
external memory operations. The use of these bits is
discussed in Section 8.3 “Wait States”.
The WM bits select the particular operating mode used
when the bus is operating in 16-Bit Data Width mode.
These are discussed in more detail in Section 8.6
“16-Bi t Data Wid th Mo des”. These bits have no effect
when an 8-Bit Data Width mode is selected.
REGISTER 8-1: MEMCON: EXTERNAL MEMORY BUS CONTROL REGISTER(1)
R/W-0 U-0 R/W-0 R/W-0 U-0 U-0 R/W-0 R/W-0
EBDIS —WAIT1WAIT0——WM1WM0
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 EBDIS: External Bus Disable bit
1 = External bus is enabled when microcontroller accesses external memory; otherwise, all external
bus drivers are mapped as I/O ports
0 = External bus is always enabled, I/O ports are disabled
bit 6 Unimplemented: Read as ‘0’
bit 5-4 WAIT<1:0>: Table Reads and Writes Bus Cycle Wait Count bits
11 = Table reads and writes will wait 0 TCY
10 = Table reads and writes will wait 1 TCY
01 = Table reads and writes will wait 2 TCY
00 = Table reads and writes will wait 3 TCY
bit 3-2 Unimplemented: Read as ‘0’
bit 1-0 WM<1:0>: TBLWT Operation with 16-Bit Data Bus Width Select bits
1x = Word Write mode: TABLAT word output, WRH active when TABLAT is written
01 = Byte Select mode: TABLAT data copied on both MSB and LSB, WRH and (UB or LB) will activate
00 = Byte Write mode: TABLAT data copied on both MSB and LSB, WRH or WRL will activate
Note 1: Unimplemented on 64-pin devices (PIC18F6XK22), read as ‘0’.
2011 Microchip Technology Inc. DS39960C-page 123
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8.2 Address and Data Width
The PIC18F87K22 family of devices can be indepen-
dently configured for different address and data widths
on the same memory bus. Both address and data width
are set by Configuration bits in the CONFIG3L register.
As Configuration bits, this means that these options
can only be configured by programming the device and
are not controllable in software.
The BW bit selects an 8-bit or 16-bit data bus width.
Setting this bit (default) selects a data width of 16 bits.
The ABW<1:0> bits determine both the program mem-
ory operating mode and the address bus width. The
available options are 20-bit, 16-bit and 12-bit, as well
as Microcontroller mode (external bus disabled).
Selecting a 16-bit or 12-bit width makes a correspond-
ing number of high-order lines available for I/O
functions. These pins are no longer affected by the
setting of the EBDIS bit. For example, selecting a
16-Bit Addressing mode (ABW<1:0> = 01) disables
A<19:16> and allows PORTH<3:0> to function without
interruptions from the bus. Using the smaller address
widths allows users to tailor the memory bus to the size
of the external memory space for a particular design
while freeing up pins for dedicated I/O operation.
Because the ABW bits have the effect of disabling pins
for memory bus operations, it is important to always
select an address width at least equal to the data width.
If a 12-bit address width is used with a 16-bit data
width, the upper four bits of data will not be available on
the bus.
All combinations of address and data widths require
multiplexing of address and data information on the
same lines. The address and data multiplexing, as well
as I/O ports made available by the use of smaller
address widths, are summarized in Ta bl e 8 - 2 .
8.2.1 ADDRESS SHIFTING ON THE
EXTERNAL BUS
By default, the address presented on the external bus
is the value of the PC. In practical terms, this means
that addresses in the external memory device below
the top of on-chip memory are unavailable to the micro-
controller. To access these physical locations, the glue
logic between the microcontroller and the external
memory must somehow translate addresses.
To simplify the interface, the external bus offers an
extension of Extended Microcontroller mode that
automatically performs address shifting. This feature is
controlled by the EASHFT Configuration bit. Setting
this bit offsets addresses on the bus by the size of the
microcontroller’s on-chip program memory and sets
the bottom address at 0000h. This allows the device to
use the entire range of physical addresses of the
external memory.
8.2.2 21-BIT ADDRESSING
As an extension of 20-bit address width operation, the
external memory bus can also fully address a 2-Mbyte
memory space. This is done by using the Bus Address
bit 0 (BA0) control line as the Least Significant bit of the
address. The UB and LB control signals may also be
used with certain memory devices to select the upper
and lower bytes within a 16-bit wide data word.
This addressing mode is available in both 8-bit and
certain 16-Bit Data Width modes. Additional details are
provided in Section 8.6.3 “16-Bit Byte Select Mode”
and Section 8.7 “8-Bit Data Width Mode”.
TABLE 8-2: ADDRESS AND DATA LINES FOR DIFFERENT ADDRESS AND DATA WIDTHS
Data Width Address Width Multiplexed Data and
Address Lines (and
Corresponding Ports)
Address Only Lines
(and Corresponding
Ports)
Ports Available
for I/O
8-bit
12-bit
AD<7:0>
(PORTD<7:0>)
AD<11:8>
(PORTE<3:0>)
PORTE<7:4>,
All of PORTH
16-bit AD<15:8>
(PORTE<7:0>) All of PORTH
20-bit
A<19:16>, AD<15:8>
(PORTH<3:0>,
PORTE<7:0>)
—
16-bit
16-bit AD<15:0>
(PORTD<7:0>,
PORTE<7:0>)
— All of PORTH
20-bit A<19:16>
(PORTH<3:0>) —
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8.3 W ait States
While it may be assumed that external memory devices
will operate at the microcontroller clock rate, this is
often not the case. In fact, many devices require longer
times to write or retrieve data than the time allowed by
the execution of table read or table write operations.
To compensate for this, the external memory bus can
be configured to add a fixed delay to each table opera-
tion using the bus. Wait states are enabled by setting
the WAIT Configuration bit. When enabled, the amount
of delay is set by the WAIT<1:0> bits (MEMCON<5:4>).
The delay is based on multiples of microcontroller
instruction cycle time and is added following the
instruction cycle when the table operation is executed.
The range is from no delay to 3 TCY (default value).
8.4 Port Pin Weak Pull -ups
With the exception of the upper address lines,
A<19:16>, the pins associated with the external mem-
ory bus are equipped with weak pull-ups. The pull-ups
are controlled by the upper three bits of the PADCFG1
register (PADCFG1<7:5>). They are named RDPU,
REPU and RJPU and control pull-ups on PORTD,
PORTE and PORTJ, respectively. Setting one of these
bits enables the corresponding pull-ups for that port. All
pull-ups are disabled by default on all device Resets.
In Extended Microcontroller mode, the port pull-ups
can be useful in preserving the memory state on the
external bus while the bus is temporarily disabled
(EBDIS = 1).
8.5 Program Memory Modes and the
External Memory Bus
The PIC18F87K22 family of devices is capable of
operating in one of two program memory modes, using
combinations of on-chip and external program memory.
The functions of the multiplexed port pins depend on
the program memory mode selected, as well as the
setting of the EBDIS bit.
In Microcontroller M ode, the bus is not active and the
pins have their port functions only. Writes to the
MEMCOM register are not permitted. The Reset value
of EBDIS (‘0’) is ignored and the ABW pins behave as
I/O ports.
In Extended Microcontroller Mode, the external
program memory bus shares I/O port functions on the
pins. When the device is fetching or doing table
read/table write operations on the external program
memory space, the pins will have the external bus
function.
If the device is fetching and accessing internal program
memory locations only, the EBDIS control bit will
change the pins from external memory to I/O port
functions. When EBDIS = 0, the pins function as the
external bus. When EBDIS = 1, the pins function as I/O
ports.
If the device fetches or accesses external memory
while EBDIS = 1, the pins will switch to the external
bus. If the EBDIS bit is set by a program executing from
external memory, the action of setting the bit will be
delayed until the program branches into the internal
memory. At that time, the pins will change from external
bus to I/O ports.
If the device is executing out of internal memory when
EBDIS = 0, the memory bus address/data and control
pins will not be active. They will go to a state where the
active address/data pins are tri-state; the CE, OE,
WRH, WRL, UB and LB signals are ‘1’, and ALE and
BA0 are ‘0’. Note that only those pins associated with
the current address width are forced to tri-state; the
other pins continue to function as I/O. In the case of
16-bit address width, for example, only AD<15:0>
(PORTD and PORTE) are affected; A<19:16>
(PORTH<3:0>) continue to function as I/O.
In all external memory modes, the bus takes priority
over any other peripherals that may share pins with it.
This includes the Parallel Master Port and serial
communication modules which would otherwise take
priority over the I/O port.
8.6 16-Bit Data Wi dth Modes
In 16-Bit Data Width mode, the external memory
interface can be connected to external memories in
three different configurations:
• 16-Bit Byte Write
•16-Bit Word Write
• 16-Bit Byte Select
The configuration to be used is determined by the
WM<1:0> bits in the MEMCON register
(MEMCON<1:0>). These three different configurations
allow the designer maximum flexibility in using both
8-bit and 16-bit devices with 16-bit data.
For all 16-bit modes, the Address Latch Enable (ALE)
pin indicates that the address bits, AD<15:0>, are avail-
able on the external memory interface bus. Following
the address latch, the Output Enable (OE) signal will
enable both bytes of program memory at once to form
a 16-bit instruction word. The Chip Enable (CE signal)
is active at any time that the microcontroller accesses
external memory, whether reading or writing; it is
inactive (asserted high) whenever the device is in
Sleep mode.
In Byte Select mode, JEDEC standard Flash memories
will require BA0 for the byte address line and one I/O
line to select between Byte and Word mode. The other
16-bit modes do not need BA0. JEDEC standard static
RAM memories will use the UB or LB signals for byte
selection.
2011 Microchip Technology Inc. DS39960C-page 125
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8.6.1 16-BIT BYTE WRITE MODE
Figure 8-1 shows an example of 16-Bit Byte Write
mode for PIC18F87K22 family devices. This mode is
used for two separate 8-bit memories connected for
16-bit operation. This generally includes basic EPROM
and Flash devices. It allows table writes to byte-wide
external memories.
During a TBLWT instruction cycle, the TABLAT data is
presented on the upper and lower bytes of the
AD<15:0> bus. The appropriate WRH or WRL control
line is strobed on the LSb of the TBLPTR.
FIGURE 8-1: 16-BIT BYTE WRITE MODE EXAMPLE
AD<7:0>
A<19:16>(1)
ALE
D<15:8>
373 A<x:0>
D<7:0>
A<19:0> A<x:0>
D<7:0>
373
OE
WRH
OE OE
WR(2) WR(2)
CE CE
Note 1: Upper order address lines are used only for 20-bit address widths.
2: This signal only applies to table writes. See Section 7.1 “Table Reads and Tab le Writes” .
WRL
D<7:0>
(LSB)
(MSB)
D<7:0>
AD<15:8>
Address Bus
Data Bus
Control Lines
CE
PIC18F87K22
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DS39960C-page 126 2011 Microchip Technology Inc.
8.6.2 16-BIT WORD WRITE MODE
Figure 8-2 shows an example of 16-Bit Word Write
mode for PIC18F87K22 family devices. This mode is
used for word-wide memories, which includes some of
the EPROM and Flash-type memories. This mode
allows opcode fetches and table reads from all forms of
16-bit memory and table writes to any type of
word-wide external memories. This method makes a
distinction between TBLWT cycles to even or odd
addresses.
During a TBLWT cycle to an even address
(TBLPTR<0> = 0), the TABLAT data is transferred to a
holding latch and the external address data bus is
tri-stated for the data portion of the bus cycle. No write
signals are activated.
During a TBLWT cycle to an odd address
(TBLPTR<0> = 1), the TABLAT data is presented on
the upper byte of the AD<15:0> bus. The contents of
the holding latch are presented on the lower byte of the
AD<15:0> bus.
The WRH signal is strobed for each write cycle; the
WRL pin is unused. The signal on the BA0 pin indicates
the LSb of the TBLPTR, but it is left unconnected.
Instead, the UB and LB signals are active to select both
bytes. The obvious limitation to this method is that the
table write must be done in pairs on a specific word
boundary to correctly write a word location.
FIGURE 8-2: 16-BIT WORD WRITE MODE EXAMPLE
AD<7:0>
AD<15:8>
ALE
373 A<20:1>
373
OE
WRH
A<19:16>(1)
A<x:0>
D<15:0>
OE WR(2)
CE
D<15:0>
JEDEC Word
EPROM Memory
Address Bus
Data Bus
Control Lines
Note 1: Upper order address lines are used only for 20-bit address widths.
2: This signal only applies to table writes. See Section 7.1 “Table Reads and Table Writes”.
CE
PIC18F87K22
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8.6.3 16-BIT BYTE SELECT MODE
Figure 8-3 shows an example of 16-Bit Byte Select
mode. This mode allows table write operations to
word-wide external memories with byte selection
capability. This generally includes both word-wide
Flash and SRAM devices.
During a TBLWT cycle, the TABLAT data is presented
on the upper and lower byte of the AD<15:0> bus. The
WRH signal is strobed for each write cycle; the WRL
pin is not used. The BA0 or UB/LB signals are used to
select the byte to be written, based on the Least
Significant bit of the TBLPTR register.
Flash and SRAM devices use different control signal
combinations to implement Byte Select mode. JEDEC
standard Flash memories require that a controller I/O
port pin be connected to the memory’s BYTE/WORD
pin to provide the select signal. They also use the BA0
signal from the controller as a byte address. JEDEC
standard static RAM memories, on the other hand, use
the UB or LB signals to select the byte.
FIGURE 8-3: 16-BIT BYTE SELECT MODE EX AMP LE
AD<7:0>
AD<15:8>
ALE
373
A<20:1>
373
OE
WRH
A<19:16>(2)
WRL
BA0
JEDEC Word
A<x:1>
D<15:0>
A<20:1>
CE
D<15:0>
I/O
OE WR(1)
A0
BYTE/WORD
FLASH Memor y
JEDEC Word
A<x:1>
D<15:0>
CE
D<15:0>
OE WR(1)
LB
UB
SRAM Memory
LB
UB
138(3)
Address Bus
Data Bus
Control Lines
Note 1: This signal only applies to table writes. See Section 7.1 “Table Reads and Table Writes” .
2: Upper order address lines are used only for 20-bit address width.
3: Demultiplexing is only required when multiple memory devices are accessed.
PIC18F87K22
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DS39960C-page 128 2011 Microchip Technology Inc.
8.6.4 16-BIT MODE TIMING
The presentation of control signals on the external
memory bus is different for the various operating
modes. Typical signal timing diagrams are shown in
Figure 8-4 and Figure 8-5.
FIGURE 8-4: EXTERN AL MEMORY BUS TIMING FOR TBLRD
(EXTENDED MICROCONTROLLER MODE)
FIGURE 8-5: EXTERN AL MEMORY BUS TIMING FOR SLEEP
(EXTENDED MICROCONTROLLER MODE)
Q2Q1 Q3 Q4 Q2Q1 Q3 Q4 Q2Q1 Q3 Q4
A<19:16>
ALE
OE
AD<15:0>
CE
Opcode Fetch Opcode Fetch Opcode Fetch
TBLRD *
TBLRD Cycle 1
ADDLW 55h
from 000100h
Q2Q1 Q3 Q4
0Ch
CF33h
TBLRD 92h
from 199E67h
9256h
from 000104h
Memory
Cycle
Instruction
Execution INST(PC – 2) TBLRD Cycle 2
MOVLW 55h
from 000102h
MOVLW
Q2Q1 Q3 Q4 Q2Q1 Q3 Q4
A<19:16>
ALE
OE
3AAAh
AD<15:0>
00h 00h
CE
Opcode Fetch Opcode Fetch
SLEEP
SLEEP
from 007554h
Q1
Bus Inactive
0003h
3AABh
0E55h
Memory
Cycle
Instruction
Execution INST(PC – 2)
Sleep Mode,
MOVLW 55h
from 007556h
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8.7 8-Bit Dat a Wid th Mode
In 8-Bit Data Width mode, the external memory bus
operates only in Multiplexed mode; that is, data shares
the 8 Least Significant bits of the address bus.
Figure 8-6 shows an example of 8-Bit Multiplexed
mode for PIC18F8XK22 devices. This mode is used for
a single, 8-bit memory connected for 16-bit operation.
The instructions will be fetched as two 8-bit bytes on a
shared data/address bus. The two bytes are sequen-
tially fetched within one instruction cycle (TCY).
Therefore, the designer must choose external memory
devices according to timing calculations based on
1/2 TCY (2 times the instruction rate). For proper mem-
ory speed selection, glue logic propagation delay times
must be considered, along with setup and hold times.
The Address Latch Enable (ALE) pin indicates that the
address bits, AD<15:0>, are available on the external
memory interface bus. The Output Enable (OE) signal
will enable one byte of program memory for a portion of
the instruction cycle, then BA0 will change and the
second byte will be enabled to form the 16-bit instruc-
tion word. The Least Significant bit of the address, BA0,
must be connected to the memory devices in this
mode. The Chip Enable (CE) signal is active at any
time that the microcontroller accesses external
memory, whether reading or writing. It is inactive
(asserted high) whenever the device is in Sleep mode.
This generally includes basic EPROM and Flash
devices. It allows table writes to byte-wide external
memories.
During a TBLWT instruction cycle, the TABLAT data is
presented on the upper and lower bytes of the
AD<15:0> bus. The appropriate level of the BA0 control
line is strobed on the LSb of the TBLPTR.
FIGURE 8-6: 8-BIT MULTIPLEXED MODE EXAMPLE
AD<7:0>
A<19:16>(1)
ALE D<15:8>
373 A<19:0> A<x:1>
D<7:0>
OE
OE WR(2)
CE
Note 1: Upper order address bits are only used for 20-bit address width. The upper AD byte is used for all
address widths except 8-bit.
2: This signal only applies to table writes. See S ecti on 7.1 “Tab le Reads and Table Writes”.
WRL
D<7:0>
AD<15:8>(1)
Address Bus
Data Bus
Control Lines
CE
A0
BA0
PIC18F87K22
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DS39960C-page 130 2011 Microchip Technology Inc.
8.7.1 8-BIT MODE TIMING
The presentation of control signals on the external
memory bus is different for the various operating
modes. Typical signal timing diagrams are shown in
Figure 8-7 and Figure 8-8.
FIGURE 8-7: EXTERN AL MEMORY BUS TIMING FOR TBLRD
(EXTENDED MICROCONTROLLER MODE)
FIGURE 8-8: EXTERN AL MEMO RY BUS TIMING FOR SLEEP
(EXTENDED MICROCONTROLLER MODE)
Q2Q1 Q3 Q4 Q2Q1 Q3 Q4 Q2Q1 Q3 Q4
A<19:16>
ALE
OE
AD<7:0>
CE
Opcode Fetch Opcode Fetch Opcode Fetch
TBLRD *
TBLRD Cycle 1
ADDLW 55h
from 000100h
Q2Q1 Q3 Q4
0Ch
33h
TBLRD 92h
from 199E67h
92h
from 000104h
Memory
Cycle
Instruction
Execution INST(PC – 2) TBLRD Cycle 2
MOVLW 55h
from 000102h
MOVLW
AD<15:8> CFh
Q2Q1 Q3 Q4 Q2Q1 Q3 Q4
A<19:16>
ALE
OE
AAh
AD<7:0>
00h 00h
CE
Opcode Fetch Opcode Fetch
SLEEP
SLEEP
from 007554h
Q1
Bus Inactive
00h ABh 55h
Memory
Cycle
Instruction
Execution INST(PC – 2)
Sleep Mode,
MOVLW 55h
from 007556h
AD<15:8> 3Ah 3Ah
03h 0Eh
BA0
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8.8 Operation in Power-Managed
Modes
In alternate, power-managed Run modes, the external
bus continues to operate normally. If a clock source
with a lower speed is selected, bus operations will run
at that speed. In these cases, excessive access times
for the external memory may result if Wait states have
been enabled and added to external memory opera-
tions. If operations in a lower power Run mode are
anticipated, users should provide in their applications
for adjusting memory access times at the lower clock
speeds.
In Sleep and Idle modes, the microcontroller core does
not need to access data; bus operations are
suspended. The state of the external bus is frozen, with
the address/data pins and most of the control pins hold-
ing at the same state they were in when the mode was
invoked. The only potential changes are to the CE, LB
and UB pins, which are held at logic high.
TABLE 8-3: REGISTERS ASSOCIATED WITH THE EXTERNAL MEMORY BUS
Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
MEMCON(1) EBDIS —WAIT1WAIT0——WM1WM0
PADCFG1 RDPU REPU RJPU(1) — — RTSECSEL1 RTSECSEL0 —
PMD1 PSPMD CTMUMD RTCCMD TMR4MD TMR3MD TMR2MD TMR1MD EMBMD
Legend: — = unimplemented, read as ‘0’. Shaded cells are not used during external memory bus access.
Note 1: Unimplemented in 64-pin devices (PIC18F6XK22), read as ‘0’.
PIC18F87K22 FAMILY
DS39960C-page 132 2011 Microchip Technology Inc.
NOTES:
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9.0 DATA EEPROM MEMORY
The data EEPROM is a nonvolatile memory array,
separate from the data RAM and program memory, that
is used for long-term storage of program data. It is not
directly mapped in either the register file or program
memory space, but is indirectly addressed through the
Special Function Registers (SFRs). The EEPROM is
readable and writable during normal operation over the
entire VDD range.
Five SFRs are used to read and write to the data
EEPROM, as well as the program memory. They are:
• EECON1
• EECON2
• EEDATA
• EEADR
• EEADRH
The data EEPROM allows byte read and write. When
interfacing to the data memory block, EEDATA holds
the 8-bit data for read/write and the EEADRH:EEADR
register pair holds the address of the EEPROM location
being accessed.
The EEPROM data memory is rated for high erase/write
cycle endurance. A byte write automatically erases the
location and writes the new data (erase-before-write).
The write time is controlled by an on-chip timer; it will
vary with voltage and temperature, as well as from chip-
to-chip. Please refer to Parameter D122 (Table 31-1 in
Section 31.0 “Electrical Characteristics”) for exact
limits.
9.1 EEADR and EEADRH Registers
The EEADRH:EEADR register pair is used to address
the data EEPROM for read and write operations.
EEADRH holds the two MSbs of the address; the upper
6 bits are ignored. The 10-bit range of the pair can
address a memory range of 1024 bytes (00h to 3FFh).
9.2 EECON1 and EECON2 Registers
Access to the data EEPROM is controlled by two
registers: EECON1 and EECON2. These are the same
registers which control access to the program memory
and are used in a similar manner for the data
EEPROM.
The EECON1 register (Register 9-1) is the control
register for data and program memory access. Control
bit, EEPGD, determines if the access will be to program
memory or data EEPROM memory. When clear,
operations will access the data EEPROM memory.
When set, program memory is accessed.
Control bit, CFGS, determines if the access will be to
the Configuration registers or to program memory/data
EEPROM memory. When set, subsequent operations
access Configuration registers. When CFGS is clear,
the EEPGD bit selects either program Flash or data
EEPROM memory.
The WREN bit, when set, will allow a write operation.
On power-up, the WREN bit is clear. The WRERR bit is
set in hardware when the WREN bit is set, and cleared,
when the internal programming timer expires and the
write operation is complete.
The WR control bit initiates write operations. The bit
cannot be cleared, only set, in software; it is cleared in
hardware at the completion of the write operation.
Control bits, RD and WR, start read and erase/write
operations, respectively. These bits are set by firmware
and cleared by hardware at the completion of the
operation.
The RD bit cannot be set when accessing program
memory (EEPGD = 1). Program memory is read using
table read instructions. See Section 7.1 “Table Reads
and Table Writes” regarding table reads.
The EECON2 register is not a physical register. It is
used exclusively in the memory write and erase
sequences. Reading EECON2 will read all ‘0’s.
Note: During normal operation, the WRERR is
read as ‘1’. This can indicate that a write
operation was prematurely terminated by
a Reset or a write operation was
attempted improperly.
Note: The EEIF interrupt flag bit (PIR6<4>) is
set when the write is complete; it must be
cleared in software.
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DS39960C-page 134 2011 Microchip Technology Inc.
REGISTER 9-1: EECON1: DATA EEPROM CONTROL REGISTER 1
R/W-x R/W-x U-0 R/W-0 R/W-x R/W-0 R/S-0 R/S-0
EEPGD CFGS — FREE WRERR(1) WREN WR RD
bit 7 bit 0
Legend: S = Settable bit
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 EEPGD: Flash Program or Data EEPROM Memory Select bit
1 = Access Flash program memory
0 = Access data EEPROM memory
bit 6 CFGS: Flash Program/Data EEPROM or Configuration Select bit
1 = Access Configuration registers
0 = Access Flash program or data EEPROM memory
bit 5 Unimplemented: Read as ‘0’
bit 4 FREE: Flash Row Erase Enable bit
1 = Erase the program memory row addressed by TBLPTR on the next WR command (cleared by
completion of erase operation)
0 = Perform write-only
bit 3 WRERR: Flash Program/Data EEPROM Error Flag bit(1)
1 = A write operation is prematurely terminated (any Reset during self-timed programming in normal
operation or an improper write attempt)
0 = The write operation has completed
bit 2 WREN: Flash Program/Data EEPROM Write Enable bit
1 = Allows write cycles to Flash program/data EEPROM
0 = Inhibits write cycles to Flash program/data EEPROM
bit 1 WR: Write Control bit
1 = Initiates a data EEPROM erase/write cycle, or a program memory erase cycle or write cycle.
(The operation is self-timed and the bit is cleared by hardware once the write is complete.
The WR bit can only be set (not cleared) in software.)
0 = Write cycle to the EEPROM is complete
bit 0 RD: Read Control bit
1 = Initiates an EEPROM read
(Read takes one cycle. RD is cleared in hardware. The RD bit can only be set (not cleared) in
software. The RD bit cannot be set when EEPGD = 1 or CFGS = 1.)
0 = Does not initiate an EEPROM read
Note 1: When a WRERR occurs, the EEPGD and CFGS bits are not cleared. This allows tracing of the error
condition.
2011 Microchip Technology Inc. DS39960C-page 135
PIC18F87K22 FAMILY
9.3 Reading the Dat a EEPROM
Memory
To read a data memory location, the user must write the
address to the EEADRH:EEADR register pair, clear the
EEPGD control bit (EECON1<7>) and then set control
bit, RD (EECON1<0>). The data is available in the
EEDATA register after one cycle; therefore, it can be
read after one NOP instruction. EEDATA will hold this
value until another read operation or until it is written to
by the user (during a write operation).
The basic process is shown in Example 9-1.
9.4 Writing to the Data EEPROM
Memory
To write an EEPROM data location, the address must
first be written to the EEADRH:EEADR register pair
and the data written to the EEDATA register. The
sequence in Example 9-2 must be followed to initiate
the write cycle.
The write will not begin if this sequence is not exactly
followed (write 0x55 to EECON2, write 0xAA to
EECON2, then set WR bit) for each byte. It is strongly
recommended that interrupts be disabled during this
code segment.
Additionally, the WREN bit in EECON1 must be set to
enable writes. This mechanism prevents accidental
writes to data EEPROM due to unexpected code exe-
cution (i.e., runaway programs). The WREN bit should
be kept clear at all times, except when updating the
EEPROM. The WREN bit is not cleared by hardware.
After a write sequence has been initiated, EECON1,
EEADRH:EEADR and EEDATA cannot be modified.
The WR bit will be inhibited from being set unless the
WREN bit is set. The WREN bit must be set on a
previous instruction. Both WR and WREN cannot be
set with the same instruction.
At the completion of the write cycle, the WR bit is
cleared in hardware and the EEPROM Interrupt Flag bit
(EEIF) is set. The user may either enable this interrupt,
or poll this bit. EEIF must be cleared by software.
9.5 Write Veri fy
Depending on the application, good programming
practice may dictate that the value written to the
memory should be verified against the original value.
This should be used in applications where excessive
writes can stress bits near the specification limit.
Note: Self-write execution to Flash and
EEPROM memory cannot be done while
running in LP Oscillator mode (Low-Power
mode). Therefore, executing a self-write
will put the device into High-Power mode.
PIC18F87K22 FAMILY
DS39960C-page 136 2011 Microchip Technology Inc.
EXAMPLE 9-1: DATA EEPROM READ
EXAMPLE 9-2: DATA EEPROM WRITE
MOVLW DATA_EE_ADDRH ;
MOVWF EEADRH ; Upper bits of Data Memory Address to read
MOVLW DATA_EE_ADDR ;
MOVWF EEADR ; Lower bits of Data Memory Address to read
BCF EECON1, EEPGD ; Point to DATA memory
BCF EECON1, CFGS ; Access EEPROM
BSF EECON1, RD ; EEPROM Read
NOP
MOVF EEDATA, W ; W = EEDATA
MOVLW DATA_EE_ADDRH ;
MOVWF EEADRH ; Upper bits of Data Memory Address to write
MOVLW DATA_EE_ADDR ;
MOVWF EEADR ; Lower bits of Data Memory Address to write
MOVLW DATA_EE_DATA ;
MOVWF EEDATA ; Data Memory Value to write
BCF EECON1, EEPGD ; Point to DATA memory
BCF EECON1, CFGS ; Access EEPROM
BSF EECON1, WREN ; Enable writes
BCF INTCON, GIE ; Disable Interrupts
MOVLW 0x55 ;
Required MOVWF EECON2 ; Write 55h
Sequence MOVLW 0xAA ;
MOVWF EECON2 ; Write 0AAh
BSF EECON1, WR ; Set WR bit to begin write
BTFSC EECON1, WR ; Wait for write to complete GOTO $-2
BSF INTCON, GIE ; Enable Interrupts
; User code execution
BCF EECON1, WREN ; Disable writes on write complete (EEIF set)
2011 Microchip Technology Inc. DS39960C-page 137
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9.6 Operation During Code-Protect
Data EEPROM memory has its own code-protect bits in
Configuration Words. External read and write
operations are disabled if code protection is enabled.
The microcontroller itself can both read and write to the
internal data EEPROM, regardless of the state of the
code-protect Configuration bit. Refer to Section 28.0
“Special Features of the CPU” for additional
information.
9.7 Protection Against Spurious Write
There are conditions when the device may not want to
write to the data EEPROM memory. To protect against
spurious EEPROM writes, various mechanisms have
been implemented. On power-up, the WREN bit is
cleared. In addition, writes to the EEPROM are blocked
during the Power-up Timer period (TPWRT,
Parameter 33).
The write initiate sequence, and the WREN bit
together, help prevent an accidental write during
brown-out, power glitch or software malfunction.
9.8 Using the Data EEPROM
The data EEPROM is a high-endurance, byte address-
able array that has been optimized for the storage of
frequently changing information (e.g., program
variables or other data that is updated often).
Frequently changing values will typically be updated
more often than specification, D124. If this is not the
case, an array refresh must be performed. For this
reason, variables that change infrequently (such as
constants, IDs, calibration, etc.) should be stored in
Flash program memory.
A simple data EEPROM refresh routine is shown in
Example 9-3.
EXAMPLE 9-3: DATA EEPROM REFRESH ROUTINE
Note: If data EEPROM is only used to store
constants and/or data that changes often,
an array refresh is likely not required. See
specification, D124.
CLRF EEADR ; Start at address 0
CLRF EEADRH ;
BCF EECON1, CFGS ; Set for memory
BCF EECON1, EEPGD ; Set for Data EEPROM
BCF INTCON, GIE ; Disable interrupts
BSF EECON1, WREN ; Enable writes
LOOP ; Loop to refresh array
BSF EECON1, RD ; Read current address
MOVLW 0x55 ;
MOVWF EECON2 ; Write 55h
MOVLW 0xAA ;
MOVWF EECON2 ; Write 0AAh
BSF EECON1, WR ; Set WR bit to begin write
BTFSC EECON1, WR ; Wait for write to complete
BRA $-2
INCFSZ EEADR, F ; Increment address
BRA LOOP ; Not zero, do it again
INCFSZ EEADRH, F ; Increment the high address
BRA LOOP ; Not zero, do it again
BCF EECON1, WREN ; Disable writes
BSF INTCON, GIE ; Enable interrupts
PIC18F87K22 FAMILY
DS39960C-page 138 2011 Microchip Technology Inc.
TABLE 9-1: REGISTERS ASSOCIATED WITH DATA EEPROM MEMORY
Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
INTCON GIE/GIEH PEIE/GIEL TMR0IE INT0IE RBIE TMR0IF INT0IF RBIF
EEADRH EEPROM Address Register High Byte
EEADR EEPROM Address Register Low Byte
EEDATA EEPROM Data Register
EECON2 EEPROM Control Register 2 (not a physical register)
EECON1 EEPGD CFGS — FREE WRERR WREN WR RD
IPR6 — — — EEIP —CMP3IP CMP2IP CMP1IP
PIR6 — — — EEIF —CMP3IF CMP2IF CMP1IF
PIE6 — — — EEIE —CMP3IE CMP2IE CMP1IE
Legend: — = unimplemented, read as ‘0’. Shaded cells are not used during Flash/EEPROM access.
2011 Microchip Technology Inc. DS39960C-page 139
PIC18F87K22 FAMILY
10.0 8 x 8 HARDWARE MULTIPLIER
10.1 Introduction
All PIC18 devices include an 8 x 8 hardware multiplier
as part of the ALU. The multiplier performs an unsigned
operation and yields a 16-bit result that is stored in the
product register pair, PRODH:PRODL. The multiplier’s
operation does not affect any flags in the STATUS
register.
Making multiplication a hardware operation allows it to
be completed in a single instruction cycle. This has the
advantages of higher computational throughput and
reduced code size for multiplication algorithms and
allows PIC18 devices to be used in many applications
previously reserved for digital-signal processors. A
comparison of various hardware and software multiply
operations, along with the savings in memory and
execution time, is shown in Table 10-1.
10.2 Operation
Example 10-1 shows the instruction sequence for an 8 x
8 unsigned multiplication. Only one instruction is
required when one of the arguments is already loaded in
the WREG register.
Example 10-2 shows the sequence to do an 8 x 8
signed multiplication. To account for the sign bits of the
arguments, each argument’s Most Significant bit (MSb)
is tested and the appropriate subtractions are done.
EXAMPLE 10- 1: 8 x 8 UNSIGNED
MULTIP LY ROU TI N E
EXAMPLE 10-2: 8 x 8 SIGNED MULTIPLY
ROUTINE
TABLE 10-1: PERFORMANCE COMP ARISON FOR VARIOUS MULTIPLY OPERATIONS
MOVF ARG1, W ;
MULWF ARG2 ; ARG1 * ARG2 ->
; PRODH:PRODL
MOVF ARG1, W
MULWF ARG2 ; ARG1 * ARG2 ->
; PRODH:PRODL
BTFSC ARG2, SB ; Test Sign Bit
SUBWF PRODH, F ; PRODH = PRODH
; - ARG1
MOVF ARG2, W
BTFSC ARG1, SB ; Test Sign Bit
SUBWF PRODH, F ; PRODH = PRODH
; - ARG2
Routine Multiply Method Program
Memory
(Words)
Cycles
(Max)
Time
@ 64 MHz @ 48 MHz @ 10 MHz @ 4 MHz
8 x 8 unsigned Without hardware multiply 13 69 4.3 s5.7 s27.6 s69 s
Hardware multiply 1 1 62.5 ns 83.3 ns 400 ns 1 s
8 x 8 signed Without hardware multiply 33 91 5.6 s7.5 s36.4 s91 s
Hardware multiply 6 6 375 ns 500 ns 2.4 s6 s
16 x 16
unsigned
Without hardware multiply 21 242 15.1 s20.1 s96.8 s 242 s
Hardware multiply 28 28 1.7 s2.3 s11.2 s28 s
16 x 16 signed Without hardware multiply 52 254 15.8 s21.2 s 101.6 s 254 s
Hardware multiply 35 40 2.5 s3.3 s16.0 s40 s
PIC18F87K22 FAMILY
DS39960C-page 140 2011 Microchip Technology Inc.
Example 10-3 shows the sequence to do a 16 x 16
unsigned multiplication. Equation 10-1 shows the
algorithm that is used. The 32-bit result is stored in four
registers (RES3:RES0).
EQUATION 10-1: 16 x 16 UNSIGNED
MULTIPLICATION
ALGORITHM
EXAMPLE 10- 3: 16 x 16 UNSIGNED
MULTIPLY ROUTINE
Example 10-4 shows the sequence to do a 16 x 16
signed multiply. Equation 10-2 shows the algorithm
used. The 32-bit result is stored in four registers
(RES3:RES0). To account for the sign bits of the
arguments, the MSb for each argument pair is tested
and the appropriate subtractions are done.
EQUATION 10-2: 16 x 16 SIGNED
MULTIPLICATION
ALGORITHM
EXAMPLE 10-4: 16 x 16 SIGNED
MU LTIPLY ROUTINE
RES3:RES0 = ARG1H:ARG1L ARG2H:ARG2L
= (ARG1H ARG2H 216) +
(ARG1H ARG2L 28) +
(ARG1L ARG2H 28) +
(ARG1L ARG2L)
MOVF ARG1L, W
MULWF ARG2L ; ARG1L * ARG2L->
; PRODH:PRODL
MOVFF PRODH, RES1 ;
MOVFF PRODL, RES0 ;
; MOVF ARG1H, W
MULWF ARG2H ; ARG1H * ARG2H->
; PRODH:PRODL
MOVFF PRODH, RES3 ;
MOVFF PRODL, RES2 ;
; MOVF ARG1L, W
MULWF ARG2H ; ARG1L * ARG2H->
; PRODH:PRODL
MOVF PRODL, W ;
ADDWF RES1, F ; Add cross
MOVF PRODH, W ; products
ADDWFC RES2, F ;
CLRF WREG ;
ADDWFC RES3, F ;
; MOVF ARG1H, W ;
MULWF ARG2L ; ARG1H * ARG2L->
; PRODH:PRODL
MOVF PRODL, W ;
ADDWF RES1, F ; Add cross
MOVF PRODH, W ; products
ADDWFC RES2, F ;
CLRF WREG ;
ADDWFC RES3, F ;
RES3:RES0= ARG1H:ARG1L ARG2H:ARG2L
= (ARG1H ARG2H 216) +
(ARG1H ARG2L 28) +
(ARG1L ARG2H 28) +
(ARG1L ARG2L) +
(-1 ARG2H<7> ARG1H:ARG1L 216) +
(-1 ARG1H<7> ARG2H:ARG2L 216)
MOVF ARG1L, W
MULWF ARG2L ; ARG1L * ARG2L ->
; PRODH:PRODL
MOVFF PRODH, RES1 ;
MOVFF PRODL, RES0 ;
; MOVF ARG1H, W
MULWF ARG2H ; ARG1H * ARG2H ->
; PRODH:PRODL
MOVFF PRODH, RES3 ;
MOVFF PRODL, RES2 ;
; MOVF ARG1L, W
MULWF ARG2H ; ARG1L * ARG2H ->
; PRODH:PRODL
MOVF PRODL, W ;
ADDWF RES1, F ; Add cross
MOVF PRODH, W ; products
ADDWFC RES2, F ;
CLRF WREG ;
ADDWFC RES3, F ;
; MOVF ARG1H, W ;
MULWF ARG2L ; ARG1H * ARG2L ->
; PRODH:PRODL
MOVF PRODL, W ;
ADDWF RES1, F ; Add cross
MOVF PRODH, W ; products
ADDWFC RES2, F ;
CLRF WREG ;
ADDWFC RES3, F ;
; BTFSS ARG2H, 7 ; ARG2H:ARG2L neg?
BRA SIGN_ARG1 ; no, check ARG1
MOVF ARG1L, W ;
SUBWF RES2 ;
MOVF ARG1H, W ;
SUBWFB RES3 ;
SIGN_ARG1
BTFSS ARG1H, 7 ; ARG1H:ARG1L neg?
BRA CONT_CODE ; no, done
MOVF ARG2L, W ;
SUBWF RES2 ;
MOVF ARG2H, W ;
SUBWFB RES3
;
CONT_CODE
:
2011 Microchip Technology Inc. DS39960C-page 141
PIC18F87K22 FAMILY
11.0 INTERRUPTS
Members of the PIC18F87K22 family of devices have
multiple interrupt sources and an interrupt priority
feature that allows most interrupt sources to be
assigned a high-priority level or a low-priority level. The
high-priority interrupt vector is at 0008h and the
low-priority interrupt vector is at 0018h. High-priority
interrupt events will interrupt any low-priority interrupts
that may be in progress.
The registers for controlling interrupt operation are:
• RCON
•INTCON
• INTCON2
• INTCON3
• PIR1, PIR2, PIR3
• PIE1, PIE2, PIE3
• IPR1, IPR2, IPR3
It is recommended that the Microchip header files
supplied with MPLAB® IDE be used for the symbolic bit
names in these registers. This allows the
assembler/compiler to automatically take care of the
placement of these bits within the specified register.
In general, interrupt sources have three bits to control
their operation. They are:
•Flag bit – Indicating that an interrupt event
occurred
•Enable bit – Enabling program execution to
branch to the interrupt vector address when the
flag bit is set
•Priority bit – Specifying high priority or low priority
The interrupt priority feature is enabled by setting the
IPEN bit (RCON<7>). When interrupt priority is
enabled, there are two bits that enable interrupts
globally. Setting the GIEH bit (INTCON<7>) enables all
interrupts that have the priority bit set (high priority).
Setting the GIEL bit (INTCON<6>) enables all
interrupts that have the priority bit cleared (low priority).
When the interrupt flag, enable bit and appropriate
global interrupt enable bit are set, the interrupt will
vector immediately to address, 0008h or 0018h,
depending on the priority bit setting. Individual
interrupts can be disabled through their corresponding
enable bits.
When the IPEN bit is cleared (default state), the
interrupt priority feature is disabled and interrupts are
compatible with PIC® mid-range devices. In
Compatibility mode, the interrupt priority bits for each
source have no effect. INTCON<6> is the PEIE bit that
enables/disables all peripheral interrupt sources.
INTCON<7> is the GIE bit that enables/disables all
interrupt sources. All interrupts branch to address
0008h in Compatibility mode.
When an interrupt is responded to, the global interrupt
enable bit is cleared to disable further interrupts. If the
IPEN bit is cleared, this is the GIE bit. If interrupt priority
levels are used, this will be either the GIEH or GIEL bit.
High-priority interrupt sources can interrupt a
low-priority interrupt. Low-priority interrupts are not
processed while high-priority interrupts are in progress.
The return address is pushed onto the stack and the
PC is loaded with the interrupt vector address (0008h
or 0018h). Once in the Interrupt Service Routine, the
source(s) of the interrupt can be determined by polling
the interrupt flag bits. The interrupt flag bits must be
cleared in software before re-enabling interrupts to
avoid recursive interrupts.
The “return from interrupt” instruction, RETFIE, exits
the interrupt routine and sets the GIE bit (GIEH or GIEL
if priority levels are used) that re-enables interrupts.
For external interrupt events, such as the INTx pins or
the PORTB input change interrupt, the interrupt latency
will be three to four instruction cycles. The exact
latency is the same for one or two-cycle instructions.
Individual interrupt flag bits are set regardless of the
status of their corresponding enable bit or the GIE bit.
Note: Do not use the MOVFF instruction to modify
any of the Interrupt Control registers while
any interrupt is enabled. Doing so may
cause erratic microcontroller behavior.
PIC18F87K22 FAMILY
DS39960C-page 142 2011 Microchip Technology Inc.
FIGURE 11 -1: PIC18F87 K22 FAMILY INTERRUPT LOGIC
TMR0IE
GIE/GIEH
PEIE/GIEL
Wake-up if in
Interrupt to CPU
Vector to Location
0008h
INT2IF
INT2IE
INT2IP
INT1IF
INT1IE
INT1IP
TMR0IF
TMR0IE
TMR0IP
RBIF
RBIE
RBIP
IPEN
TMR0IF
TMR0IP
INT1IF
INT1IE
INT1IP
INT2IF
INT2IE
INT2IP
RBIF
RBIE
RBIP
INT0IF
INT0IE
PEIE/GIEL
Interrupt to CPU
Vector to Location
IPEN
IPEN
0018h
PIR1<7:0>
PIE1<7:0>
IPR1<7:0>
High-Priority Interrupt Generation
Low-Priority Interrupt Generation
Idle or Sleep modes
GIE/GIEH
INT3IF
INT3IE
INT3IP
INT3IF
INT3IE
INT3IP
PIR2<7,5:0>
PIE2<7,5:0>
IPR2<7,5:0>
PIR3<7,5>
PIE3<7,5>
IPR3<7,5>
PIR1<7:0>
PIE1<7:0>
IPR1<7:0>
PIR2<7, 5:0>
PIE2<7, 5:0>
IPR2<7, 5:0>
PIR3<7, 5:0>
PIE3<7, 5:0>
IPR3<7, 5:0>
IPEN
PIR4<7:0>
PIE4<7:0>
IPR4<7:0>
PIR5<7:0>
PIE5<7:0>
IPR5<7:0>
PIR6<4, 2:0>
PIE6<4, 2:0>
IPR6<4, 2:0>
PIR4<7:0>
PIE4<7:0>
IPR4<7:0>
PIR5<7:0>
PIE5<7:0>
IPR5<7:0>
PIR6<4, 2:0>
PIE6<4, 2:0>
IPR6<4, 2:0>
2011 Microchip Technology Inc. DS39960C-page 143
PIC18F87K22 FAMILY
11.1 INTCON Registers
The INTCON registers are readable and writable
registers that contain various enable, priority and flag
bits.
Note: Interrupt flag bits are set when an interrupt
condition occurs regardless of the state of
its corresponding enable bit or the global
interrupt enable bit. User software should
ensure the appropriate interrupt flag bits
are clear prior to enabling an interrupt.
This feature allows for software polling.
REGISTER 11-1: INTCON: INTERRUPT CONTROL REGISTER
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-x
GIE/GIEH PEIE/GIEL TMR0IE INT0IE RBIE TMR0IF INT0IF RBIF(1)
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 GIE/GIEH: Global Interrupt Enable bit
When IPEN = 0:
1 = Enables all unmasked interrupts
0 = Disables all interrupts
When IPEN = 1:
1 = Enables all high-priority interrupts
0 = Disables all interrupts
bit 6 PEIE/GIEL: Peripheral Interrupt Enable bit
When IPEN = 0:
1 = Enables all unmasked peripheral interrupts
0 = Disables all peripheral interrupts
When IPEN = 1:
1 = Enables all low-priority peripheral interrupts
0 = Disables all low-priority peripheral interrupts
bit 5 TMR0IE: TMR0 Overflow Interrupt Enable bit
1 = Enables the TMR0 overflow interrupt
0 = Disables the TMR0 overflow interrupt
bit 4 INT0IE: INT0 External Interrupt Enable bit
1 = Enables the INT0 external interrupt
0 = Disables the INT0 external interrupt
bit 3 RBIE: RB Port Change Interrupt Enable bit
1 = Enables the RB port change interrupt
0 = Disables the RB port change interrupt
bit 2 TMR0IF: TMR0 Overflow Interrupt Flag bit
1 = TMR0 register has overflowed (Bit must be cleared in software.)
0 = TMR0 register did not overflow
bit 1 INT0IF: INT0 External Interrupt Flag bit
1 = The INT0 external interrupt occurred (must be cleared in software)
0 = The INT0 external interrupt did not occur
bit 0 RBIF: RB Port Change Interrupt Flag bit(1)
1 = At least one of the RB<7:4> pins changed state (must be cleared in software)
0 = None of the RB<7:4> pins have changed state
Note 1: A mismatch condition will continue to set this bit. Reading PORTB, and then waiting one additional instruction
cycle, will end the mismatch condition and allow the bit to be cleared.
PIC18F87K22 FAMILY
DS39960C-page 144 2011 Microchip Technology Inc.
REGISTER 11-2: INTCON2: INTERRUPT CONTROL REGISTER 2
R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1
RBPU INTEDG0 INTEDG1 INTEDG2 INTEDG3 TMR0IP INT3IP RBIP
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 RBPU: PORTB Pull-up Enable bit
1 = All PORTB pull-ups are disabled
0 = PORTB pull-ups are enabled by individual port latch values
bit 6 INTEDG0: External Interrupt 0 Edge Select bit
1 = Interrupt on rising edge
0 = Interrupt on falling edge
bit 5 INTEDG1: External Interrupt 1 Edge Select bit
1 = Interrupt on rising edge
0 = Interrupt on falling edge
bit 4 INTEDG2: External Interrupt 2 Edge Select bit
1 = Interrupt on rising edge
0 = Interrupt on falling edge
bit 3 INTEDG3: External Interrupt 3 Edge Select bit
1 = Interrupt on rising edge
0 = Interrupt on falling edge
bit 2 TMR0IP: TMR0 Overflow Interrupt Priority bit
1 =High priority
0 = Low priority
bit 1 INT3IP: INT3 External Interrupt Priority bit
1 =High priority
0 = Low priority
bit 0 RBIP: RB Port Change Interrupt Priority bit
1 =High priority
0 = Low priority
Note: Interrupt flag bits are set when an interrupt condition occurs regardless of the state of its corresponding
enable bit or the global interrupt enable bit. User software should ensure the appropriate interrupt flag bits
are clear prior to enabling an interrupt. This feature allows for software polling.
2011 Microchip Technology Inc. DS39960C-page 145
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REGISTER 11-3: INTCON3: INTERRUPT CONTROL REGISTER 3
R/W-1 R/W-1 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0
INT2IP INT1IP INT3IE INT2IE INT1IE INT3IF INT2IF INT1IF
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 INT2IP: INT2 External Interrupt Priority bit
1 =High priority
0 = Low priority
bit 6 INT1IP: INT1 External Interrupt Priority bit
1 =High priority
0 = Low priority
bit 5 INT3IE: INT3 External Interrupt Enable bit
1 = Enables the INT3 external interrupt
0 = Disables the INT3 external interrupt
bit 4 INT2IE: INT2 External Interrupt Enable bit
1 = Enables the INT2 external interrupt
0 = Disables the INT2 external interrupt
bit 3 INT1IE: INT1 External Interrupt Enable bit
1 = Enables the INT1 external interrupt
0 = Disables the INT1 external interrupt
bit 2 INT3IF: INT3 External Interrupt Flag bit
1 = The INT3 external interrupt occurred (Bit must be cleared in software.)
0 = The INT3 external interrupt did not occur
bit 1 INT2IF: INT2 External Interrupt Flag bit
1 = The INT2 external interrupt occurred (must be cleared in software)
0 = The INT2 external interrupt did not occur
bit 0 INT1IF: INT1 External Interrupt Flag bit
1 = The INT1 external interrupt occurred (must be cleared in software)
0 = The INT1 external interrupt did not occur
Note: Interrupt flag bits are set when an interrupt condition occurs regardless of the state of its corresponding
enable bit or the global interrupt enable bit. User software should ensure the appropriate interrupt flag bits
are clear prior to enabling an interrupt. This feature allows for software polling.
PIC18F87K22 FAMILY
DS39960C-page 146 2011 Microchip Technology Inc.
11.2 PIR Registers
The PIR registers contain the individual flag bits for the
peripheral interrupts. Due to the number of peripheral
interrupt sources, there are six Peripheral Interrupt
Request (Flag) registers (PIR1 through PIR6).
Note 1: Interrupt flag bits are set when an interrupt
condition occurs regardless of the state of
its corresponding enable bit or the Global
Interrupt Enable bit, GIE (INTCON<7>).
2: User software should ensure the
appropriate interrupt flag bits are cleared
prior to enabling an interrupt and after
servicing that interrupt.
REGISTER 11-4: PIR1: PERIPHERAL INTERRUPT REQUEST (FLAG) REGISTER 1
U-0 R/W-0 R-0 R-0 R/W-0 R/W-0 R/W-0 R/W-0
PSPIF ADIF RC1IF TX1IF SSP1IF TMR1GIF TMR2IF TMR1IF
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 PSPIF: Parallel Slave Port Read/Write Interrupt Flag bit
1 = A read or write operation has taken place (must be cleared in software)
0 = No read or write operation has occurred
bit 6 ADIF: A/D Converter Interrupt Flag bit
1 = An A/D conversion completed (must be cleared in software)
0 = The A/D conversion is not complete
bit 5 RC1IF: EUSART Receive Interrupt Flag bit
1 = The EUSART receive buffer, RCREG1, is full (cleared when RCREG1 is read)
0 = The EUSART receive buffer is empty
bit 4 TX1IF: EUSART Transmit Interrupt Flag bit
1 = The EUSART transmit buffer, TXREG1, is empty (cleared when TXREG1 is written)
0 = The EUSART transmit buffer is full
bit 3 SSP1IF: Master Synchronous Serial Port Interrupt Flag bit
1 = The transmission/reception is complete (must be cleared in software)
0 = Waiting to transmit/receive
bit 2 TMR1GIF: Timer1 Gate Interrupt Flag bit
1 = Timer gate interrupt occurred (This must be cleared in software.)
0 = No timer gate interrupt occurred
bit 1 TMR2IF: TMR2 to PR2 Match Interrupt Flag bit
1 = TMR2 to PR2 match occurred (must be cleared in software)
0 = No TMR2 to PR2 match occurred
bit 0 TMR1IF: TMR1 Overflow Interrupt Flag bit
1 = TMR1 register overflowed (must be cleared in software)
0 = TMR1 register did not overflow
2011 Microchip Technology Inc. DS39960C-page 147
PIC18F87K22 FAMILY
REGISTER 11-5: PIR2: PERIPHERAL INTERRUPT REQUEST (FLAG) REGISTER 2
R/W-0 U-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0
OSCFIF — SSP2IF BCL2IF BCL1IF HLVDIF TMR3IF TMR3GIF
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 OSCFIF: Oscillator Fail Interrupt Flag bit
1 = Device oscillator failed, clock input has changed to INTOSC (bit must be cleared in software)
0 = Device clock is operating
bit 6 Unimplemented: Read as ‘0’
bit 5 SSP2IF: Master Synchronous Serial Port Interrupt Flag bit
1 = The transmission/reception has been completed (bit must be cleared in software)
0 = Waiting to transmit/receive
bit 4 BCL2IF: Bus Collision Interrupt Flag bit
1 = A bus collision occurred (bit must be cleared in software)
0 = No bus collision occurred
bit 3 BCL1IF: Bus Collision Interrupt Flag bit
1 = A bus collision occurred (bit must be cleared in software)
0 = No bus collision occurred
bit 2 HLVDIF: High/Low-Voltage Detect Interrupt Flag bit
1 = A low-voltage condition occurred (bit must be cleared in software)
0 = The device voltage is above the regulator’s low-voltage trip point
bit 1 TMR3IF: TMR3 Overflow Interrupt Flag bit
1 = TMR3 register overflowed (bit must be cleared in software)
0 = TMR3 register did not overflow
bit 0 TMR3GIF: TMR3 Gate Interrupt Flag bit
1 = Timer gate interrupt occurred (bit must be cleared in software)
0 = No timer gate interrupt occurred
PIC18F87K22 FAMILY
DS39960C-page 148 2011 Microchip Technology Inc.
REGISTER 11-6: PIR3: PERIPHERAL INTERRUPT REQUEST (FLAG) REGISTER 3
R/W-0 R/W-0 R-0 R-0 R/W-0 R/W-0 R/W-0 R/W-0
TMR5GIF — RC2IF TX2IF CTMUIF CCP2IF CCP1IF RTCCIF
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 TMR5GIF: Timer5 Gate Interrupt Flag bit
1 = Timer gate interrupt occurred (bit must be cleared in software)
0 = No timer gate interrupt occurred
bit 6 Unimplemented: Read as ‘0’
bit 5 RC2IF: EUSART Receive Interrupt Flag bit
1 = The EUSART receive buffer, RCREG2, is full (cleared when RCREG2 is read)
0 = The EUSART receive buffer is empty
bit 4 TX2IF: EUSART Transmit Interrupt Flag bit
1 = The EUSART transmit buffer, TXREG2, is empty (cleared when TXREG2 is written)
0 = The EUSART transmit buffer is full
bit 3 CTMUIF: CTMU Interrupt Flag bit
1 = CTMU interrupt occurred (must be cleared in software)
0 = No CTMU interrupt occurred
bit 2 CCP2IF: ECCP2 Interrupt Flag bit
Capture mode:
1 = A TMR register capture occurred (must be cleared in software)
0 = No TMR register capture occurred
Compare mode:
1 = A TMR register compare match occurred (must be cleared in software)
0 = No TMR register compare match occurred
PWM mode:
Unused in this mode.
bit 1 CCP1IF: ECCP1 Interrupt Flag bit
Capture mode:
1 = A TMR register capture occurred (must be cleared in software)
0 = No TMR register capture occurred
Compare mode:
1 = A TMR register compare match occurred (must be cleared in software)
0 = No TMR register compare match occurred
PWM mode:
Unused in this mode.
bit 0 RTCCIF: RTCC Interrupt Flag bit
1 = RTCC interrupt occurred (must be cleared in software)
0 = No RTCC interrupt occurred
2011 Microchip Technology Inc. DS39960C-page 149
PIC18F87K22 FAMILY
REGISTER 11-7: PIR4: PERIPHERAL INTERRUPT REQUEST (FLAG) REGISTER 4
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0
CCP10IF(1) CCP9IF(1) CCP8IF CCP7IF CCP6IF CCP5IF CCP4IF CCP3IF
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7-1 CCP<10:4>IF: CCP<10:4> Interrupt Flag bits(1)
Capture Mode:
1 = A TMR register capture occurred (bit must be cleared in software)
0 = No TMR register capture occurred
Compare Mode:
1 = A TMR register compare match occurred (must be cleared in software)
0 = No TMR register compare match occurred
PWM Mode:
Not used in PWM mode.
bit 0 CCP3IF: ECCP3 Interrupt Flag bits
Capture Mode:
1 = A TMR register capture occurred (bit must be cleared in software)
0 = No TMR register capture occurred
Compare Mode:
1 = A TMR register compare match occurred (must be cleared in software)
0 = No TMR register compare match occurred
PWM Mode:
Not used in PWM mode.
Note 1: Unimplemented on devices with a program memory of 32 Kbytes (PIC18FX5K22).
PIC18F87K22 FAMILY
DS39960C-page 150 2011 Microchip Technology Inc.
REGISTER 11-8: PIR5: PERIPHERAL INTERRUPT REQUEST (FLAG) REGISTER 5
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0
TMR7GIF(1) TMR12IF(1) TMR10IF(1) TMR8IF TMR7IF(1) TMR6IF TMR5IF TMR4IF
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 TMR7GIF: TMR7 Gate Interrupt Flag bits(1)
1 = TMR gate interrupt occurred (bit must be cleared in software)
0 = No TMR gate occurred
bit 6 TMR12IF: TMR12 to PR12 Match Interrupt Flag bit(1)
1 = TMR12 to PR12 match occurred (must be cleared in software)
0 = No TMR12 to PR12 match occurred
bit 5 TMR10IF: TMR10 to PR10 Match Interrupt Flag bit(1)
1 = TMR10 to PR10 match occurred (must be cleared in software)
0 = No TMR10 to PR10 match occurred
bit 4 TMR8IF: TMR8 to PR8 Match Interrupt Flag bit
1 = TMR8 to PR8 match occurred (must be cleared in software)
0 = No TMR8 to PR8 match occurred
bit 3 TMR7IF: TMR7 Overflow Interrupt Flag bit(1)
1 = TMR7 register overflowed (must be cleared in software)
0 = TMR7 register did not overflow
bit 2 TMR6IF: TMR6 to PR6 Match Interrupt Flag bit
1 = TMR6 to PR6 match occurred (must be cleared in software)
0 = No TMR6 to PR6 match occurred
bit 1 TMR5IF: TMR5 Overflow Interrupt Flag bit
1 = TMR5 register overflowed (must be cleared in software)
0 = TMR5 register did not overflow
bit 0 TMR4IF: TMR4 to PR4 Match Interrupt Flag bit
1 = TMR4 to PR4 match occurred (must be cleared in software)
0 = No TMR4 to PR4 match occurred
Note 1: Unimplemented on devices with a program memory of 32 Kbytes (PIC18FX5K22).
2011 Microchip Technology Inc. DS39960C-page 151
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REGISTER 11-9: PIR6: PERIPHERAL INTERRUPT REQUEST (FLAG) REGISTER 6
U-0 U-0 U-0 R/W-0 U-0 R/W-0 R/W-0 R/W-0
— — — EEIF — CMP3IF CMP2IF CMP1IF
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7-5 Unimplemented: Read as ‘0’
bit 4 EEIF: Data EEDATA/Flash Write Operation Interrupt Flag bit
1 = The write operation is complete (must be cleared in software)
0 = The write operation is not complete or has not been started
bit 3 Unimplemented: Read as ‘0’
bit 2 CMP3IF: CMP3 Interrupt Flag bit
1 = CMP3 interrupt occurred (must be cleared in software)
0 = No CMP3 interrupt occurred
bit 1 CMP2IF: CMP2 Interrupt Flag bit
1 = CMP2 interrupt occurred (must be cleared in software)
0 = No CMP2 interrupt occurred
bit 0 CMP1IF: CM1 Interrupt Flag bit
1 = CMP1 interrupt occurred (must be cleared in software)
0 = No CMP1 interrupt occurred
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DS39960C-page 152 2011 Microchip Technology Inc.
11.3 PIE Registers
The PIE registers contain the individual enable bits for
the peripheral interrupts. Due to the number of
peripheral interrupt sources, there are six Peripheral
Interrupt Enable registers (PIE1 through PIE6). When
IPEN (RCON<7>) = 0, the PEIE bit must be set to
enable any of these peripheral interrupts.
REGISTER 11-10: PIE1: PERIPHERAL INTERRUPT ENABLE REGISTER 1
U-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0
PSPIE ADIE RC1IE TX1IE SSP1IE TMR1GIE TMR2IE TMR1IE
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 PSPIE: Parallel Slave Port Read/Write Interrupt Enable bit
1 = Enables the PSP read/write interrupt
0 = Disables the PSP read/write interrupt
bit 6 ADIE: A/D Converter Interrupt Enable bit
1 = Enables the A/D interrupt
0 = Disables the A/D interrupt
bit 5 RC1IE: EUSART Receive Interrupt Enable bit
1 = Enables the EUSART receive interrupt
0 = Disables the EUSART receive interrupt
bit 4 TX1IE: EUSART Transmit Interrupt Enable bit
1 = Enables the EUSART transmit interrupt
0 = Disables the EUSART transmit interrupt
bit 3 SSP1IE: Master Synchronous Serial Port Interrupt Enable bit
1 = Enables the MSSP interrupt
0 = Disables the MSSP interrupt
bit 2 TMR1GIE: TMR1 Gate Interrupt Enable bit
1 = Enables the gate
0 = Disabled the gate
bit 1 TMR2IE: TMR2 to PR2 Match Interrupt Enable bit
1 = Enables the TMR2 to PR2 match interrupt
0 = Disables the TMR2 to PR2 match interrupt
bit 0 TMR1IE: TMR1 Overflow Interrupt Enable bit
1 = Enables the TMR1 overflow interrupt
0 = Disables the TMR1 overflow interrupt
2011 Microchip Technology Inc. DS39960C-page 153
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REGISTER 11-11: PIE2: PERIPHERAL INTERRUPT ENABLE REGISTER 2
R/W-0 U-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0
OSCFIE — SSP2IE BCL2IE BCL1IE HLVDIE TMR3IE TMR3GIE
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 OSCFIE: Oscillator Fail Interrupt Enable bit
1 = Enabled
0 = Disabled
bit 6 Unimplemented: Read as ‘0’
bit 5 SSP2IE: Master Synchronous Serial Port 2 Interrupt Enable bit
1 = Enables the MSSP interrupt
0 = Disables the MSSP interrupt
bit 4 BCL2IE: Bus Collision Interrupt Enable bit
1 = Enables the bus collision interrupt
0 = Disables the bus collision interrupt
bit 3 BCL1IE: Bus Collision Interrupt Enable bit
1 = Enabled
0 = Disabled
bit 2 HLVDIE: High/Low-Voltage Detect Interrupt Enable bit
1 = Enabled
0 = Disabled
bit 1 TMR3IE: TMR3 Overflow Interrupt Enable bit
1 = Enabled
0 = Disabled
bit 0 TMR3GIE: Timer3 Gate Interrupt Enable bit
1 = Enabled
0 = Disabled
PIC18F87K22 FAMILY
DS39960C-page 154 2011 Microchip Technology Inc.
REGISTER 11-12: PIE3: PERIPHERAL INTERRUPT ENABLE REGISTER 3
R/W-0 R/W-0 R-0 R-0 R/W-0 R/W-0 R/W-0 R/W-0
TMR5GIE — RC2IE TX2IE CTMUIE CCP2IE CCP1IE RTCCIE
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 TMR5GIE: Timer5 Gate Interrupt Enable bit
1 = Enabled
0 = Disabled
bit 6 Unimplemented: Read as ‘0’
bit 5 RC2IE: EUSART Receive Interrupt Enable bit
1 = Enabled
0 = Disabled
bit 4 TX2IE: EUSART Transmit Interrupt Enable bit
1 = Enabled
0 = Disabled
bit 3 CTMUIE: CTMU Interrupt Enable bit
1 = Enabled
0 = Disabled
bit 2 CCP2IE: ECCP2 Interrupt Enable bit
1 = Enabled
0 = Disabled
bit 1 CCP1IE: ECCP1 Interrupt Enable bit
1 = Enabled
0 = Disabled
bit 0 RTCCIE: RTCC Interrupt Enable bit
1 = Enabled
0 = Disabled
REGISTER 11-13: PIE4: PERIPHERAL INTERRUPT ENABLE REGISTER 4
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0
CCP10IE(1) CCP9IE(1) CCP8IE CCP7IE CCP6IE CCP5IE CCP4IE CCP3IE
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7-0 CCP<10:3>IE: CCP<10:3> Interrupt Enable bits(1)
1 = Enabled
0 =Disabled
Note 1: Unimplemented on devices with a program memory of 32 Kbytes (PIC18FX5K22).
2011 Microchip Technology Inc. DS39960C-page 155
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REGISTER 11-14: PIE5: PERIPHERAL INTERRUPT ENABLE REGISTER 5
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0
TMR7GIE(1) TMR12IE(1) TMR10IE(1) TMR8IE TMR7IE(1) TMR6IE TMR5IE TMR4IE
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 TMR7GIE: TMR7 Gate Interrupt Enable bit(1)
1 = Enabled
0 =Disabled
bit 6 TMR12IE: TMR12 to PR12 Match Interrupt Enable bit(1)
1 = Enables the TMR12 to PR12 match interrupt
0 = Disables the TMR12 to PR12 match interrupt
bit 5 TMR10IE: TMR10 to PR10 Match Interrupt Enable bit(1)
1 = Enables the TMR10 to PR10 match interrupt
0 = Disables the TMR10 to PR10 match interrupt
bit 4 TMR8IE: TMR8 to PR8 Match Interrupt Enable bit
1 = Enables the TMR8 to PR8 match interrupt
0 = Disables the TMR8 to PR8 match interrupt
bit 3 TMR7IE: TMR7 Overflow Interrupt Enable bit(1)
1 = Enables the TMR7 overflow interrupt
0 = Disables the TMR7 overflow interrupt
bit 2 TMR6IE: TMR6 to PR6 Match Interrupt Enable bit
1 = Enables the TMR6 to PR6 match interrupt
0 = Disables the TMR6 to PR6 match interrupt
bit 1 TMR5IE: TMR5 Overflow Interrupt Enable bit
1 = Enables the TMR5 overflow interrupt
0 = Disables the TMR5 overflow interrupt
bit 0 TMR4IE: TMR4 to PR4 Match Interrupt Enable bit
1 = Enables the TMR4 to PR4 match interrupt
0 = Disables the TMR4 to PR4 match interrupt
Note 1: Unimplemented on devices with a program memory of 32 Kbytes (PIC18FX5K22).
PIC18F87K22 FAMILY
DS39960C-page 156 2011 Microchip Technology Inc.
REGISTER 11-15: PIE6: PERIPHERAL INTERRUPT ENABLE REGISTER 6
U-0 U-0 U-0 R/W-0 U-0 R/W-0 R/W-0 R/W-0
— — — EEIE — CMP3IE CMP2IE CMP1IE
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7-5 Unimplemented: Read as ‘0’
bit 4 EEIE: Data EEDATA/Flash Write Operation Enable bit
1 = Interrupt is enabled
0 = interrupt is disabled
bit 3 Unimplemented: Read as ‘0’
bit 2 CMP3IE: CMP3 Enable bit
1 = Interrupt is enabled
0 = interrupt is disabled
bit 1 CMP2E: CMP2 Enable bit
1 = Interrupt is enabled
0 = interrupt is disabled
bit 0 CMP1IE: CMP1 Enable bit
1 = Interrupt is enabled
0 = interrupt is disabled
2011 Microchip Technology Inc. DS39960C-page 157
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11.4 IPR R e g is t e rs
The IPR registers contain the individual priority bits for
the peripheral interrupts. Due to the number of
peripheral interrupt sources, there are six Peripheral
Interrupt Priority registers (IPR1 through IPR6). Using
the priority bits requires that the Interrupt Priority
Enable (IPEN) bit (RCON<7>) be set.
REGISTER 11-16: IPR1: PERIPHERAL INTERRUPT PRIORITY REGISTER 1
R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1
PSPIP ADIP RC1IP TX1IP SSP1IP TMR1GIP TMR2IP TMR1IP
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 PSPIP: Parallel Slave Port Read/Write Interrupt Priority bit
1 =High priority
0 = Low priority
bit 6 ADIP: A/D Converter Interrupt Priority bit
1 =High priority
0 = Low priority
bit 5 RC1IP: EUSART Receive Interrupt Priority bit
1 =High priority
0 = Low priority
bit 4 TX1IP: EUSART Transmit Interrupt Priority bit
1 =High priority
0 = Low priority
bit 3 SSP1IP: Master Synchronous Serial Port Interrupt Priority bit
1 =High priority
0 = Low priority
bit 2 TMR1GIP: Timer1 Gate Interrupt Priority bit
1 =High priority
0 = Low priority
bit 1 TMR2IP: TMR2 to PR2 Match Interrupt Priority bit
1 =High priority
0 = Low priority
bit 0 TMR1IP: TMR1 Overflow Interrupt Priority bit
1 =High priority
0 = Low priority
PIC18F87K22 FAMILY
DS39960C-page 158 2011 Microchip Technology Inc.
REGISTER 11-17: IPR2: PERIPHERAL INTERRUPT PRIORITY REGISTER 2
R/W-1 U-0 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1
OSCFIP — SSP2IP BCL2IP BCL1IP HLVDIP TMR3IP TMR3GIP
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 OSCFIP: Oscillator Fail Interrupt Priority bit
1 =High priority
0 = Low priority
bit 6 Unimplemented: Read as ‘0’
bit 5 SSP2IP: Master Synchronous Serial Port 2 Interrupt Priority bit
1 =High priority
0 = Low priority
bit 4 BCL2IP: Bus Collision Interrupt priority bit (MSSP)
1 =High priority
0 = Low priority
bit 3 BCL1IP: Bus Collision Interrupt Priority bit
1 =High priority
0 = Low priority
bit 2 HLVDIP: High/Low-Voltage Detect Interrupt Priority bit
1 =High priority
0 = Low priority
bit 1 TMR3IP: TMR3 Overflow Interrupt Priority bit
1 =High priority
0 = Low priority
bit 0 TMR3GIP: TMR3 Gate Interrupt Priority bit
1 =High priority
0 = Low priority
2011 Microchip Technology Inc. DS39960C-page 159
PIC18F87K22 FAMILY
REGISTER 11-18: IPR3: PERIPHERAL INTERRUPT PRIORITY REGISTER 3
R/W-1 U-0 R-1 R-1 R/W-1 R/W-1 R/W-1 R/W-1
TMR5GIP — RC2IP TX2IP CTMUIP CCP2IP CCP1IP RTCCIP
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 TMR5GIP: Timer5 Gate interrupt Priority bit
1 =High priority
0 = Low priority
bit 6 Unimplemented: Read as ‘0’
bit 5 RC2IP: EUSART Receive Priority Flag bit
1 =High priority
0 = Low priority
bit 4 TX2IP: EUSART Transmit Interrupt Priority bit
1 =High priority
0 = Low priority
bit 3 CTMUIP: CTMU Interrupt Priority bit
1 =High priority
0 = Low priority
bit 2 CCP2IP: ECCP2 Interrupt Priority bit
1 =High priority
0 = Low priority
bit 1 CCP1IP: ECCP1 Interrupt Priority bit
1 =High priority
0 = Low priority
bit 0 RTCCIP: RTCC Interrupt Priority bit
1 =High priority
0 = Low priority
REGISTER 11-19: IPR4: PERIPHERAL INTERRUPT PRIORITY REGISTER 4
R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1
CCP10IP(1) CCP9IP(1) CCP8IP CCP7IP CCP6IP CCP5IP CCP4IP CCP3IP
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7-0 CCP<10:3>IP: CCP<10:3> Interrupt Priority bit(1)
1 = High priority
0 = Low priority
Note 1: Unimplemented on devices with a program memory of 32 Kbytes (PIC18FX5K22).
PIC18F87K22 FAMILY
DS39960C-page 160 2011 Microchip Technology Inc.
REGISTER 11-20: IPR5: PERIPHERAL INTERRUPT PRIORITY REGISTER 5
R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1
TMR7GIP(1) TMR12IP(1) TMR10IP(1) TMR8IP TMR7IP(1) TMR6IP TMR5IP TMR4IP
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 TMR7GIP: TMR7 Gate Interrupt Priority bit(1)
1 = High priority
0 = Low priority
bit 6 TMR12IP: TMR12 to PR12 Match Interrupt Priority bit(1)
1 = High priority
0 = Low priority
bit 5 TMR10IP: TMR10 to PR10 Match Interrupt Priority bit(1)
1 = High priority
0 = Low priority
bit 4 TMR8IP: TMR8 to PR8 Match Interrupt Priority bit
1 = High priority
0 = Low priority
bit 3 TMR7IP: TMR7 Overflow Interrupt Priority bit(1)
1 = High priority
0 = Low priority
bit 2 TMR6IP: TMR6 to PR6 Match Interrupt Priority bit
1 = High priority
0 = Low priority
bit 1 TMR5IP: TMR5 Overflow Interrupt Priority bit
1 = High priority
0 = Low priority
bit 0 TMR4IP: TMR4 to PR4 Match Interrupt Priority bit
1 = High priority
0 = Low priority
Note 1: Unimplemented on devices with a program memory of 32 Kbytes (PIC18FX5K22).
2011 Microchip Technology Inc. DS39960C-page 161
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REGISTER 11-21: IPR6: PERIPHERAL INTERRUPT PRIORITY REGISTER 6
U-0 U-0 U-0 R/W-1 U-0 R/W-1 R/W-1 R/W-1
— — — EEIP — CMP3IP CMP2IP CMP1IP
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7-5 Unimplemented: Read as ‘0’
bit 4 EEIP: EE Interrupt Priority bit
1 =High priority
0 = Low priority
bit 3 Unimplemented: Read as ‘0’
bit 2 CMP3IP: CMP3 Interrupt Priority bit
1 =High priority
0 = Low priority
bit 1 CMP2IP: CMP2 Interrupt Priority bit
1 =High priority
0 = Low priority
bit 0 CMP1IP: CMP1 Interrupt Priority bit
1 =High priority
0 = Low priority
PIC18F87K22 FAMILY
DS39960C-page 162 2011 Microchip Technology Inc.
11.5 RCON Register
The RCON register contains bits used to determine the
cause of the last Reset or wake-up from Idle or Sleep
modes. RCON also contains the bit that enables
interrupt priorities (IPEN).
REGISTER 11-22: RCON: RESET CONTROL REGISTER
R/W-0 R/W-1 R/W-1 R/W-1 R-1 R-1 R/W-0 R/W-0
IPEN SBOREN CM RI TO PD POR BOR
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 IPEN: Interrupt Priority Enable bit
1 = Enable priority levels on interrupts
0 = Disable priority levels on interrupts (PIC16CXXX Compatibility mode)
bit 6 SBOREN: Software BOR Enable bit
For details of bit operation, see Register 5-1.
bit 5 CM: Configuration Mismatch Flag bit
1 = A Configuration Mismatch Reset has not occurred
0 = A Configuration Mismatch Reset has occurred (must be subsequently set in software)
bit 4 RI: RESET Instruction Flag bit
For details of bit operation, see Register 5-1.
bit 3 TO: Watchdog Timer Time-out Flag bit
For details of bit operation, see Register 5-1.
bit 2 PD: Power-Down Detection Flag bit
For details of bit operation, see Register 5-1.
bit 1 POR: Power-on Reset Status bit
For details of bit operation, see Register 5-1.
bit 0 BOR: Brown-out Reset Status bit
For details of bit operation, see Register 5-1.
2011 Microchip Technology Inc. DS39960C-page 163
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11.6 INT x Pi n In te r r u pts
External interrupts on the RB0/INT0, RB1/INT1,
RB2/INT2 and RB3/INT3 pins are edge-triggered. If the
corresponding INTEDGx bit in the INTCON2 register is
set (= 1), the interrupt is triggered by a rising edge. If
that bit is clear, the trigger is on the falling edge.
When a valid edge appears on the RBx/INTx pin, the
corresponding flag bit, INTxIF, is set. This interrupt can
be disabled by clearing the corresponding enable bit,
INTxIE. Before re-enabling the interrupt, the flag bit
(INTxIF) must be cleared in software in the Interrupt
Service Routine.
All external interrupts (INT0, INT1, INT2 and INT3) can
wake up the processor from the power-managed
modes, if bit, INTxIE, was set prior to going into the
power-managed modes. If the Global Interrupt Enable
bit (GIE) is set, the processor will branch to the interrupt
vector following wake-up.
The interrupt priority for INT1, INT2 and INT3 is
determined by the value contained in the Interrupt
Priority bits, INT1IP (INTCON3<6>), INT2IP
(INTCON3<7>) and INT3IP (INTCON2<1>).
There is no priority bit associated with INT0. It is always
a high-priority interrupt source.
11.7 TM R0 Interru pt
In 8-bit mode (the default), an overflow in the TMR0
register (FFh 00h) will set flag bit, TMR0IF. In 16-bit
mode, an overflow in the TMR0H:TMR0L register pair
(FFFFh 0000h) will set TMR0IF.
The interrupt can be enabled/disabled by setting/clearing
enable bit, TMR0IE (INTCON<5>). Interrupt priority for
Timer0 is determined by the value contained in the inter-
rupt priority bit, TMR0IP (INTCON2<2>). For further
details on the Timer0 module, see Section 13.0 “Timer0
Module”.
11.8 PORTB Interrupt-on-Change
An input change on PORTB<7:4> sets flag bit, RBIF
(INTCON<0>). The interrupt can be enabled/disabled
by setting/clearing enable bit, RBIE (INTCON<3>).
Interrupt priority for PORTB interrupt-on-change is
determined by the value contained in the interrupt
priority bit, RBIP (INTCON2<0>).
11.9 Context Saving During Interrupts
During interrupts, the return PC address is saved on
the stack. Additionally, the WREG, STATUS and BSR
registers are saved on the Fast Return Stack.
If a fast return from interrupt is not used (see
Section 6.3 “Data Memory Organization”), the user
may need to save the WREG, STATUS and BSR regis-
ters on entry to the Interrupt Service Routine (ISR).
Depending on the user’s application, other registers
also may need to be saved.
Example 11-1 saves and restores the WREG, STATUS
and BSR registers during an Interrupt Service Routine.
EXAMPLE 11-1: SAVING STATUS, WREG AND BSR REGISTERS IN RAM
MOVWF W_TEMP ; W_TEMP is in virtual bank
MOVFF STATUS, STATUS_TEMP ; STATUS_TEMP located anywhere
MOVFF BSR, BSR_TEMP ; BSR_TMEP located anywhere
;
; USER ISR CODE
;
MOVFF BSR_TEMP, BSR ; Restore BSR
MOVF W_TEMP, W ; Restore WREG
MOVFF STATUS_TEMP, STATUS ; Restore STATUS
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DS39960C-page 164 2011 Microchip Technology Inc.
TABLE 11-1: SUMMARY OF REGISTERS ASSOCIATED WITH INTERRUPTS
Name Bit 7 B it 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
INTCON GIE/GIEH PEIE/GIEL TMR0IE INT0IE RBIE TMR0IF INT0IF RBIF
INTCON2 RBPU INTEDG0 INTEDG1 INTEDG2 INTEDG3 TMR0IP INT3IP RBIP
INTCON3 INT2IP INT1IP INT3IE INT2IE INT1IE INT3IF INT2IF INT1IF
PIR1 PSPIP ADIF RC1IF TX1IF SSP1IF TMR1GIF TMR2IF TMR1IF
PIR2 OSCFIF — SSP2IF BCL2IF BCL1IF HLVDIF TMR3IF TMR3GIF
PIR3 TMR5GIF — RC2IF TX2IF CTMUIF CCP2IF CCP1IF RTCCIF
PIR4 CCP10IF(1) CCP9IF(1) CCP8IF CCP7IF CCP6IF CCP5IF CCP4IF CCP3IF
PIR5 TMR7GIF(1) TMR12IF(1) TMR10IF(1) TMR8IF TMR7IF(1) TMR6IF TMR5IF TMR4IF
PIR6 — — — EEIF — CMP3IF CMP2IF CMP1IF
PIE1 PSPIE ADIE RC1IE TX1IE SSP1IE TMR1GIE TMR2IE TMR1IE
PIE2 OSCFIE — SSP2IE BCL2IE BCL1IE HLVDIE TMR3IE TMR3GIE
PIE3 TMR5GIE — RC2IE TX2IE CTMUIE CCP2IE CCP1IE RTCCIE
PIE4 CCP10IE(1) CCP9IE(1) CCP8IE CCP7IE CCP6IE CCP5IE CCP4IE CCP3IE
PIE5 TMR7GIE(1) TMR12IE(1) TMR10IE(1) TMR8IE TMR7IE(1) TMR6IE TMR5IE TMR4IE
PIE6 — — — EEIE — CMP3IE CMP2IE CMP1IE
IPR1 PSPIP ADIP RC1IP TX1IP SSP1IP TMR1GIP TMR2IP TMR1IP
IPR2 OSCFIP — SSP2IP BCL2IP BCL1IP HLVDIP TMR3IP TMR3GIP
IPR3 TMR5GIP — RC2IP TX2IP CTMUIP CCP2IP CCP1IP RTCCIP
IPR4 CCP10IP(1) CCP9IP(1) CCP8IP CCP7IP CCP6IP CCP5IP CCP4IP CCP3IP
IPR5 TMR7GIP(1) TMR12IP(1) TMR10IP(1) TMR8IP TMR7IP(1) TMR6IP TMR5IP TMR4IP
IPR6 — — — EEIP — CMP3IP CMP2IP CMP1IP
RCON IPEN SBOREN CM RI TO PD POR BOR
Legend: Shaded cells are not used by the interrupts.
Note 1: Unimplemented on devices with a program memory of 32 Kbytes (PIC18FX5K22).
2011 Microchip Technology Inc. DS39960C-page 165
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12.0 I/O PORTS
Depending on the device selected and features
enabled, there are up to nine ports available. Some
pins of the I/O ports are multiplexed with an alternate
function from the peripheral features on the device. In
general, when a peripheral is enabled, that pin may not
be used as a general purpose I/O pin.
Each port has three memory mapped registers for its
operation:
• TRIS register (Data Direction register)
• PORT register (reads the levels on the pins of the
device)
• LAT register (Output Latch register)
Reading the PORT register reads the current status of
the pins, whereas writing to the PORT register writes to
the Output Latch (LAT) register.
Setting a TRIS bit (= 1) makes the corresponding
PORT pin an input (putting the corresponding output
driver in a High-Impedance mode). Clearing a TRIS bit
(= 0) makes the corresponding port pin an output (i.e.,
put the contents of the corresponding LAT bit on the
selected pin).
The Output Latch (LAT register) is useful for
read-modify-write operations on the value that the I/O
pins are driving. Read-modify-write operations on the
LAT register read and write the latched output value for
the PORT register.
A simplified model of a generic I/O port, without the
interfaces to other peripherals, is shown in Figure 12-1.
FIGURE 12-1: GENERIC I/O PORT
OPERATION
12.1 I/O Port Pin Capabilities
When developing an application, the capabilities of the
port pins must be considered. Outputs on some pins
have higher output drive strength than others. Similarly,
some pins can tolerate higher than VDD input levels.
All of the digital ports are 5.5V input tolerant. The ana-
log ports have the same tolerance – having clamping
diodes implemented internally.
12.1.1 PIN OUTPUT DRIVE
When used as digital I/O, the output pin drive strengths
vary, according to the pins’ grouping to meet the needs
for a variety of applications. In general, there are two
classes of output pins, in terms of drive capability:
• Outputs designed to drive higher current loads
such as LEDs:
- PORTA - PORTB
-PORTC
• Outputs with lower drive levels, but capable of
driving normal digital circuit loads with a high input
impedance. Able to drive LEDs, but only those
with smaller current requirements:
- PORTD - PORTE
- PORTF - PORTG
-PORTH
(†) -PORTJ
(†)
† These ports are not available on 64-pin
devices.
12.1.2 PULL-UP CONFIGURATION
Four of the I/O ports (PORTB, PORTD, PORTE and
PORTJ) implement configurable weak pull-ups on all
pins. These are internal pull-ups that allow floating
digital input signals to be pulled to a consistent level
without the use of external resistors.
The pull-ups are enabled with a single bit for each of the
ports: RBPU (INTCON2<7>) for PORTB, and RDPU,
REPU and RJPU (PADCFG1<7:5>) for the other ports.
Data
Bus
WR LAT
WR TRIS
RD PORT
Data Latch
TRIS Latch
RD TRIS
Input
Buffer
I/O Pin
QD
CKx
QD
CKx
EN
QD
EN
RD LAT
or PORT
PIC18F87K22 FAMILY
DS39960C-page 166 2011 Microchip Technology Inc.
REGISTER 12-1: PADCFG1: PAD CONFIGURATION REGISTER
R/W-0 R/W-0 R/W-0 U-0 U-0 R/W-0 R/W-0 U-0
RDPU REPU RJPU(2) —— RTSECSEL1(1) RTSECSEL0(1) —
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 RDPU: PORTD Pull-up Enable bit
1 = PORTD pull-up resistors are enabled by individual port latch values
0 = All PORTD pull-up resistors are disabled
bit 6 REPU: PORTE Pull-up Enable bit
1 = PORTE pull-up resistors are enabled by individual port latch values
0 = All PORTE pull-up resistors are disabled
bit 5 RJPU: PORTJ Pull-up Enable bit(2)
1 = PORTJ pull-up resistors are enabled by individual port latch values
0 = All PORTJ pull-up resistors are disabled
bit 4-3 Unimplemented: Read as ‘0’
bit 2-1 RTSECSEL<1:0>: RTCC Seconds Clock Output Select bits(1)
11 = Reserved; do not use
10 = RTCC source clock is selected for the RTCC pin (pin can be LF-INTOSC or SOSC, depending on
the RTCOSC (CONFIG3L<1>) bit setting)
01 = RTCC seconds clock is selected for the RTCC pin
00 = RTCC alarm pulse is selected for the RTCC pin
bit 0 Unimplemented: Read as ‘0’
Note 1: To enable the actual RTCC output, the RTCOE (RTCCFG<2>) bit must be set.
2: Unimplemented on 64-pin devices (PIC18F6XK22), read as ‘0’.
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12.1.3 OPEN-DRAIN OUTPUTS
The output pins for several peripherals are also
equipped with a configurable, open-drain output option.
This allows the peripherals to communicate with
external digital logic, operating at a higher voltage
level, without the use of level translators.
The open-drain option is implemented on port pins
specifically associated with the data and clock outputs
of the USARTs, the MSSP module (in SPI mode) and
the CCP modules. This option is selectively enabled by
setting the open-drain control bits in the registers
ODCON1, ODCON2 and ODCON3.
When the open-drain option is required, the output pin
must also be tied through an external pull-up resistor
provided by the user to a higher voltage level, up to 5V
(Figure 12-2). When a digital logic high signal is output,
it is pulled up to the higher voltage level.
FIGURE 12-2: USING THE OPEN-DRAIN
OUTPUT (USART SHOWN
AS EXAMPLE)
TXX
+5V
3.3V
(at logic ‘1’)
3.3V
VDD 5V
PIC18F87K22
REGISTER 12-2: ODCON1: PERIPHERAL OPEN-DRAIN CONTROL REGISTER 1
R/W-0 R/W-0 R/W-0 U-0 U-0 U-0 U-0 R/W-0
SSP1OD CCP2OD CCP1OD — — — — SSP2OD
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 SSP1OD: MSSP1 Open-Drain Output Enable bit
1 = Open-drain capability is enabled
0 = Open-drain capability is disabled
bit 6 CCP2OD: ECCP2 Open-Drain Output Enable bit
1 = Open-drain capability is enabled
0 = Open-drain capability is disabled
bit 5 CCP1OD: CCP10 Open-Drain Output Enable bit
1 = Open-drain capability is enabled
0 = Open-drain capability is disabled
bit 4-1 Unimplemented: Read as ‘0’
bit 0 SSP2OD: MSSP2 Open-Drain Output Enable bit
1 = Open-drain capability is enabled
0 = Open-drain capability is disabled
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DS39960C-page 168 2011 Microchip Technology Inc.
REGISTER 12-3: ODCON2: PERIPHERAL OPEN-DRAIN CONTROL REGISTER 2
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0
CCP10OD(1) CCP9OD(1) CCP8OD CCP7OD CCP6OD CCP5OD CCP4OD CCP3OD
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 CCP10OD: CCP10 Open-Drain Output Enable bit(1)
1 = Open-drain capability is enabled
0 = Open-drain capability is disabled
bit 6 CCP9OD: CCP9 Open-Drain Output Enable bit(1)
1 = Open-drain capability is enabled
0 = Open-drain capability is disabled
bit 5 CCP8OD: CCP8 Open-Drain Output Enable bit
1 = Open-drain capability is enabled
0 = Open-drain capability is disabled
bit 4 CCP7OD: CCP7 Open-Drain Output Enable bit
1 = Open-drain capability is enabled
0 = Open-drain capability is disabled
bit 3 CCP6OD: CCP6 Open-Drain Output Enable bit
1 = Open-drain capability is enabled
0 = Open-drain capability is disabled
bit 2 CCP5OD: CCP5 Open-Drain Output Enable bit
1 = Open-drain capability is enabled
0 = Open-drain capability is disabled
bit 1 CCP4OD: CCP4 Open-Drain Output Enable bit
1 = Open-drain capability is enabled
0 = Open-drain capability is disabled
bit 0 CCP3OD: ECCP3 Open-Drain Output Enable bit
1 = Open-drain capability is enabled
0 = Open-drain capability is disabled
Note 1: Not implemented on devices with 32-byte program memory (PIC18FX5K22).
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12.1.4 ANALOG AND DIGITAL PORTS
Many of the ports multiplex analog and digital function-
ality, providing a lot of flexibility for hardware designers.
PIC18F87K22 family devices can make any analog pin
analog or digital, depending on an application’s needs.
The ports’ analog/digital functionality is controlled by
the registers: ANCON0, ANCON1 and ANCON2.
Setting these registers makes the corresponding pins
analog and clearing the registers makes the ports digi-
tal. For details on these registers, see Section 23.0
“12-Bit Analog-to-Digital Converter (A/D) Module”
REGISTER 12-4: ODCON3: PERIPHERAL OPEN-DRAIN CONTROL REGISTER 3
R/W-0 R/W-0 U-0 U-0 U-0 U-0 U-0 R/W-0
U2OD U1OD — — — — — CTMUDS
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 U2OD: EUSART2 Open-Drain Output Enable bit
1 = Open-drain capability is enabled
0 = Open-drain capability is disabled
bit 6 U1OD: EUSART1 Open-Drain Output Enable bit
1 = Open-drain capability is enabled
0 = Open-drain capability is disabled
bit 5-1 Unimplemented: Read as ‘0’
bit 0 CTMUDS: CTMU Pulse Delay Enable bit
1 = Pulse delay input for CTMU is enabled on pin, RF1
0 = Pulse delay input for CTMU is disabled on pin, RF1
PIC18F87K22 FAMILY
DS39960C-page 170 2011 Microchip Technology Inc.
12.2 PORTA, TRISA and
LATA Registers
PORTA is an 8-bit wide, bidirectional port. The corre-
sponding Data Direction and Output Latch registers are
TRISA and LATA.
RA4/T0CKI is a Schmitt Trigger input. All other PORTA
pins have TTL input levels and full CMOS output
drivers.
RA5 and RA<3:0> are multiplexed with analog inputs
for the A/D Converter.
The operation of the analog inputs as A/D Converter
inputs is selected by clearing or setting the ANSEL
control bits in the ANCON1 register. The corresponding
TRISA bits control the direction of these pins, even
when they are being used as analog inputs. The user
must ensure the bits in the TRISA register are
maintained set when using them as analog inputs.
OSC2/CLKO/RA6 and OSC1/CLKI/RA7 normally
serve as the external circuit connections for the exter-
nal (primary) oscillator circuit (HS Oscillator modes), or
the external clock input and output (EC Oscillator
modes). In these cases, RA6 and RA7 are not available
as digital I/O and their corresponding TRIS and LAT
bits are read as ‘0’. When the device is configured to
use HF-INTOSC, MF-INTOSC or LF-INTOSC as the
default oscillator mode, RA6 and RA7 are automatically
configured as digital I/O; the oscillator and clock
in/clock out functions are disabled.
RA5 has additional functionality for Timer1 and Timer3.
It can be configured as the Timer1 clock input or the
Timer3 external clock gate input.
EXAMPLE 12-1: INITIA LI ZING PORTA
Note: RA5 and RA<3:0> are configured as
analog inputs on any Reset and are read
as ‘0’. RA4 is configured as a digital input.
CLRF PORTA ; Initialize POR TA by
; clear ing ou tput la tche s
CLRF LATA ; Alternate m etho d t o
; clear ou tpu t da ta latc hes
BANKSEL ANCON1 ; Select b ank wit h A NCON 1 r egis ter
MOVLW 00h ; Configure A /D
MOVWF ANCON1 ; for digital inp uts
BANKSEL TRISA ; S elec t b ank wit h T RISA re gist er
MOVLW 0BFh ; Value used to i nit iali ze
; data dir ect ion
MOVWF TRISA ; Set RA<7 , 5 :0> as inpu ts,
; RA<6> as ou tput
2011 Microchip Technology Inc. DS39960C-page 171
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TABLE 12-1: PORTA FUNCTIONS
TABLE 12-2: SUMMARY OF REGISTERS ASSOCIATED WITH PORTA
Pin Name Functio n TRIS
Setting I/O I/O
Type Description
RA0/AN0/ULPWU RA0 0O DIG LATA<0> data output; not affected by analog input.
1I TTL PORTA<0> data input; disabled when analog input enabled.
AN0 1I ANA A/D Input Channel 0. Default input configuration on POR; does not
affect digital output.
ULPWU 1I ANA Ultra low-power wake-up input.
RA1/AN1 RA1 0O DIG LATA<1> data output; not affected by analog input.
1I TTL PORTA<1> data input; disabled when analog input enabled.
AN1 1I ANA A/D Input Channel 1. Default input configuration on POR; does not
affect digital output.
RA2/AN2/VREF-RA20O DIG LATA<2> data output; not affected by analog input.
1I TTL PORTA<2> data input; disabled when analog functions are enabled.
AN2 1I ANA A/D Input Channel 2. Default input configuration on POR.
VREF-1I ANA A/D and comparator low reference voltage input.
RA3/AN3/VREF+RA3 0O DIG LATA<3> data output; not affected by analog input.
1I TTL PORTA<3> data input; disabled when analog input is enabled.
AN3 1I ANA A/D Input Channel 3. Default input configuration on POR.
VREF+1I ANA A/D and comparator high reference voltage input.
RA4/T0CKI RA4 0O DIG LATA<4> data output.
1I ST PORTA<4> data input. Default configuration on POR.
T0CKI xI ST Timer0 clock input.
RA5/AN4/T1CKI/
T3G/HLVDIN
RA5 0O DIG LATA<5> data output; not affected by analog input.
1I TTL PORTA<5> data input; disabled when analog input enabled.
AN4 1I ANA A/D Input Channel 4. Default configuration on POR.
T1CKI xI ST Timer1 Clock Input.
T3G xI ST Timer3 External clock gate input.
HLVDIN 1I ANA High/Low-Voltage Detect external trip point input.
OSC2/CLKO/RA6 OSC2 xO ANA Main oscillator feedback output connection (HS, XT and LP modes).
CLKO xO DIG System cycle clock output (FOSC/4) (EC and INTOSC modes).
RA6 0O DIG LATA<6> data output; disabled when FOSC2 Configuration bit is set.
1I TTL PORTA<6> data input; disabled when FOSC2 Configuration bit is set.
OSC1/CLKI/RA7 OSC1 xI ANA Main oscillator input connection (HS, XT and LP modes).
CLKI xI ANA Main external clock source input (EC modes).
RA7 0O DIG LATA<7> data output; disabled when FOSC2 Configuration bit is set.
1I TTL PORTA<7> data input; disabled when FOSC2 Configuration bit is set.
Legend: O = Output, I = Input, ANA = Analog Signal, DIG = Digital Output, ST = Schmitt Trigger Buffer Input,
TTL = TTL Buffer Input, x = Don’t care (TRIS bit does not affect port direction or is overridden for this option).
Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
PORTA RA7(1) RA6(1) RA5 RA4 RA3 RA2 RA1 RA0
LATA LATA7(1) LATA6(1) LATA5 LATA4 LATA3 LATA2 LATA1 LATA0
TRISA TRISA7(1) TRISA6(1) TRISA5 TRISA4 TRISA3 TRISA2 TRISA1 TRISA0
ANCON0 ANSEL7 ANSEL6 ANSEL5 ANSEL4 ANSEL3 ANSEL2 ANSEL1 ANSEL0
Legend: — = unimplemented, read as ‘0’. Shaded cells are not used by PORTA.
Note 1: These bits are enabled depending on the oscillator mode selected. When not enabled as PORTA pins,
they are disabled and read as ‘x’.
PIC18F87K22 FAMILY
DS39960C-page 172 2011 Microchip Technology Inc.
12.3 PORTB, TRISB and
LATB Registers
PORTB is an eight-bit wide, bidirectional port. The
corresponding Data Direction and Output Latch registers
are TRISB and LATB. All pins on PORTB are digital only.
EXAMPLE 12-2: INITIALIZING PORTB
Each of the PORTB pins has a weak internal pull-up. A
single control bit can turn on all the pull-ups. This is
performed by clearing bit, RBPU (INTCON2<7>). The
weak pull-up is automatically turned off when the port
pin is configured as an output. The pull-ups are
disabled on a Power-on Reset.
Four of the PORTB pins (RB<7:4>) have an
interrupt-on-change feature. Only pins configured as
inputs can cause this interrupt to occur; any RB<7:4>
pin configured as an output being excluded from the
interrupt-on-change comparison.
Comparisons with the input pins (of RB<7:4>) are
made with the old value latched on the last read of
PORTB. The “mismatch” outputs of RB<7:4> are ORed
together to generate the RB Port Change Interrupt with
Flag bit, RBIF (INTCON<0>).
This interrupt can wake the device from
power-managed modes. To clear the interrupt in the
Interrupt Service Routine:
a) Any read or write of PORTB (except with the
MOVFF (ANY), PORTB instruction). This will
end the mismatch condition.
b) Wait one instruction cycle (such as executing a
NOP instruction).
c) Clear flag bit, RBIF.
A mismatch condition will continue to set flag bit, RBIF.
Reading PORTB will end the mismatch condition and
allow flag bit, RBIF, to be cleared after one T
CY delay.
The interrupt-on-change feature is recommended for
wake-up on key depression operation and operations
where PORTB is only used for the interrupt-on-change
feature. Polling of PORTB is not recommended while
using the interrupt-on-change feature.
The RB<3:2> pins are multiplexed as CTMU edge
inputs. RB5 has an additional function for Timer3 and
Timer1. It can be configured for Timer3 clock input or
Timer1 external clock gate input.
CLRF PORTB ; Initialize PORTB by
; clearing output
; data latches
CLRF LATB ; Alternate method
; to clear output
; data latches
MOVLW 0CFh ; Value used to
; initialize data
; direction
MOVWF TRISB ; Set RB<3:0> as inputs
; RB<5:4> as outputs
; RB<7:6> as inputs
TABLE 12-3: PORTB FUNCTIONS
Pin Name Function TRIS
Setting I/O I/O
Type Description
RB0/INT0/FLT0 RB0 0O DIG LATB<0> data output.
1I TTL PORTB<0> data input; weak pull-up when RBPU bit is cleared.
INT0 1I ST External Interrupt 0 input.
FLT0 xI ST Enhanced PWM Fault input for ECCPx.
RB1/INT1 RB1 0O DIG LATB<1> data output.
1I TTL PORTB<1> data input; weak pull-up when RBPU bit is cleared.
INT1 1I ST External Interrupt 1 input.
RB2/INT2/CTED1 RB2 0O DIG LATB<2> data output.
1I TTL PORTB<2> data input; weak pull-up when RBPU bit is cleared.
INT2 1I ST External Interrupt 2 input.
CTED1 xI ST CTMU Edge 1 input.
Legend: O = Output, I = Input, ANA = Analog Signal, DIG = Digital Output, ST = Schmitt Trigger Buffer Input,
TTL = TTL Buffer Input, x = Don’t care (TRIS bit does not affect port direction or is overridden for this option).
Note 1: Alternate assignment for ECCP2 when the CCP2MX Configuration bit is cleared and in Extended Microcontroller mode.
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TABLE 12-4: SUMMARY OF REGISTERS ASSOCIATED WITH PORTB
RB3/INT3/CTED2/
ECCP2/P2A
RB3 0O DIG LATB<3> data output.
1I TTL PORTB<3> data input; weak pull-up when RBPU bit is cleared.
INT3 1I ST External Interrupt 3 input.
CTED2 xI ST CTMU Edge 2 input.
ECCP2(1) 0O DIG ECCP2 compare output and ECCP2 PWM output.
Takes priority over port data.
1I ST ECCP2 capture input.
P2A 0O DIG ECCP2 Enhanced PWM output, Channel A.
May be configured for tri-state during Enhanced PWM shutdown
events. Takes priority over port data.
RB4/KBI0 RB4 0O DIG LATB<4> data output.
1I TTL PORTB<4> data input; weak pull-up when RBPU bit is cleared.
KBI0 1I TTL Interrupt-on-pin change.
RB5/KBI1/T3CKI/
T1G
RB5 0O DIG LATB<5> data output.
1I TTL PORTB<5> data input; weak pull-up when RBPU bit is cleared.
KBI1 1I TTL Interrupt-on-pin change.
T3CKI xI ST Timer3 clock input.
T1G xI ST Timer1 external clock gate input.
RB6/KBI2/PGC RB6 0O DIG LATB<6> data output.
1I TTL PORTB<6> data input; weak pull-up when RBPU bit is cleared.
KBI2 1I TTL Interrupt-on-pin change.
PGC xI ST Serial execution (ICSP™) clock input for ICSP and ICD operation.
RB7/KBI3/PGD RB7 0O DIG LATB<7> data output.
1I TTL PORTB<7> data input; weak pull-up when RBPU bit is cleared.
KBI3 1I TTL Interrupt-on-pin change.
PGD xO DIG Serial execution data output for ICSP and ICD operation.
xI ST Serial execution data input for ICSP and ICD operation.
Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
PORTB RB7 RB6 RB5 RB4 RB3 RB2 RB1 RB0
LATB LATB7 LATB6 LATB5 LATB4 LATB3 LATB2 LATB1 LATB0
TRISB TRISB7 TRISB6 TRISB5 TRISB4 TRISB3 TRISB2 TRISB1 TRISB0
INTCON GIE/GIEH PEIE/GIEL TMR0IE INT0IE RBIE TMR0IF INT0IF RBIF
INTCON2 RBPU INTEDG0 INTEDG1 INTEDG2 INTEDG3 TMR0IP INT3IP RBIP
INTCON3 INT2IP INT1IP INT3IE INT2IE INT1IE INT3IF INT2IF INT1IF
ODCON1 SSP1OD CCP2OD CCP1OD ————SSP2OD
Legend: Shaded cells are not used by PORTB.
TABLE 12-3: PORTB FUNCTIONS (CONTINUED)
Pin Name Function TRIS
Setting I/O I/O
Type Description
Legend: O = Output, I = Input, ANA = Analog Signal, DIG = Digital Output, ST = Schmitt Trigger Buffer Input,
TTL = TTL Buffer Input, x = Don’t care (TRIS bit does not affect port direction or is overridden for this option).
Note 1: Alternate assignment for ECCP2 when the CCP2MX Configuration bit is cleared and in Extended Microcontroller mode.
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12.4 PORTC, TRISC and
LATC Registers
PORTC is an eight-bit wide, bidirectional port. The
corresponding Data Direction and Output Latch registers
are TRISC and LATC. Only PORTC pins, RC2 through
RC7, are digital only pins.
PORTC is multiplexed with ECCP, MSSP and EUSART
peripheral functions (Ta b l e 1 2 - 5 ). The pins have
Schmitt Trigger input buffers. The pins for ECCP, SPI
and EUSART are also configurable for open-drain out-
put whenever these functions are active. Open-drain
configuration is selected by setting the SPIOD,
CCPxOD and U1OD control bits in the registers,
ODCON1 and ODCON3.
RC1 is normally configured as the default peripheral
pin for the ECCP2 module. Assignment of ECCP2 is
controlled by Configuration bit, CCP2MX (default state,
CCP2MX = 1).
When enabling peripheral functions, use care in defin-
ing TRIS bits for each PORTC pin. Some peripherals
can override the TRIS bit to make a pin an output or
input. Consult the corresponding peripheral section for
the correct TRIS bit settings.
The contents of the TRISC register are affected by
peripheral overrides. Reading TRISC always returns
the current contents, even though a peripheral device
may be overriding one or more of the pins.
EXAMPLE 12- 3: INITIALIZING PORTC
Note: These pins are configured as digital inputs
on any device Reset.
CLRF PORTC ; Initialize PORTC by
; clearing output
; data latches
CLRF LATC ; Alternate method
; to clear output
; data latches
MOVLW 0CFh ; Value used to
; initialize data
; direction
MOVWF TRISC ; Set RC<3:0> as inputs
; RC<5:4> as outputs
; RC<7:6> as inputs
TABLE 12-5: PORTC FUNCTIONS
Pin Name Function TRIS
Setting I/O I/O
Type Description
RC0/SOSCO/
SCLKI/
RC0 0O DIG LATC<0> data output.
1I ST PORTC<0> data input.
SOSCO 1I ST SOSC oscillator output.
SCLKI 1I ST Digital clock input; enabled when SOSC oscillator disabled.
RC1/SOSCI/
ECCP2/P2A
RC1 0O DIG LATC<1> data output.
1I ST PORTC<1> data input.
SOSCI xI ANA SOSC oscillator input.
ECCP2(1) 0O DIG ECCP2 compare output and ECCP2 PWM output.
Takes priority over port data.
1I ST ECCP2 Capture input.
P2A 0O DIG ECCP2 Enhanced PWM output, Channel A.
May be configured for tri-state during Enhanced PWM shutdown events. Takes
priority over port data.
RC2/ECCP1/
P1A
RC2 0O DIG LATC<2> data output.
1I ST PORTC<2> data input.
ECCP1 0O DIG ECCP1 compare output and ECCP1 PWM output. Takes priority over port data.
1I ST ECCP1 capture input.
P1A 0O DIG ECCP1 enhanced PWM output, Channel A.
May be configured for tri-state during Enhanced PWM shutdown events. Takes
priority over port data.
Legend: O = Output, I = Input, ANA = Analog Signal, DIG = Digital Output, ST = Schmitt Trigger Buffer Input, TTL = TTL Buffer Input,
I2C = I2C™/SMBus Buffer Input, x = Don’t care (TRIS bit does not affect port direction or is overridden for this option).
Note 1: Default assignment for ECCP2 when the CCP2MX Configuration bit is set.
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TABLE 12-6: SUMMARY OF REGISTERS ASSOCIATED WITH PORTC
RC3/SCK1/
SCL1
RC3 0O DIG LATC<3> data output.
1I ST PORTC<3> data input.
SCK1 0O DIG SPI clock output (MSSP module); takes priority over port data.
1I ST SPI clock input (MSSP module).
SCL1 0ODIGI
2C clock output (MSSP module); takes priority over port data.
1II
2CI
2C clock input (MSSP module); input type depends on module setting.
RC4/SDI1/
SDA1
RC4 0O DIG LATC<4> data output.
1I ST PORTC<4> data input.
SDI1 I ST SPI data input (MSSP module).
SDA1 1ODIGI
2C data output (MSSP module); takes priority over port data.
1II
2CI
2C data input (MSSP module); input type depends on module setting.
RC5/SDO1 RC5 0O DIG LATC<5> data output.
1I ST PORTC<5> data input.
SDO1 0O DIG SPI data output (MSSP module).
RC6/TX1/CK1 RC6 0O DIG LATC<6> data output.
1I ST PORTC<6> data input.
TX1 1O DIG Synchronous serial data output (EUSART module); takes priority over port data.
CK1 1O DIG Synchronous serial data input (EUSART module); user must configure as an input.
1I ST Synchronous serial clock input (EUSART module).
RC7/RX1/DT1 RC7 0O DIG LATC<7> data output.
1I ST PORTC<7> data input.
RX1 1I ST Asynchronous serial receive data input (EUSART module).
DT1 1O DIG Synchronous serial data output (EUSART module); takes priority over port data.
1I ST Synchronous serial data input (EUSART module); user must configure as an input.
Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
PORTC RC7 RC6 RC5 RC4 RC3 RC2 RC1 RC0
LATC LATC7 LATBC6 LATC5 LATCB4 LATC3 LATC2 LATC1 LATC0
TRISC TRISC7 TRISC6 TRISC5 TRISC4 TRISC3 TRISC2 TRISC1 TRISC0
ODCON1 SSP1OD CCP2OD CCP1OD — — — — SSP2OD
ODCON3 U2OD U1OD — — — — — CTMUDS
Legend: Shaded cells are not used by PORTC.
TABLE 12-5: PORTC FUNCTIONS (CONTINUED)
Pin Name Function TRIS
Setting I/O I/O
Type Description
Legend: O = Output, I = Input, ANA = Analog Signal, DIG = Digital Output, ST = Schmitt Trigger Buffer Input, TTL = TTL Buffer Input,
I2C = I2C™/SMBus Buffer Input, x = Don’t care (TRIS bit does not affect port direction or is overridden for this option).
Note 1: Default assignment for ECCP2 when the CCP2MX Configuration bit is set.
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DS39960C-page 176 2011 Microchip Technology Inc.
12.5 PORTD, TRISD and
LATD Registers
PORTD is an 8-bit wide, bidirectional port. The
corresponding Data Direction and Output Latch registers
are TRISD and LATD.
All pins on PORTD are implemented with Schmitt
Trigger input buffers. Each pin is individually
configurable as an input or output.
Each of the PORTD pins has a weak internal pull-up. A
single control bit can turn off all the pull-ups. This is
performed by setting bit, RDPU (PADCFG1<7>). The
weak pull-up is automatically turned off when the port
pin is configured as an output. The pull-ups are
disabled on all device Resets.
On 80-pin devices, PORTD is multiplexed with the
system bus as part of the external memory interface.
I/O port and other functions are only available when the
interface is disabled by setting the EBDIS bit
(MEMCON<7>). When the interface is enabled,
PORTD is the low-order byte of the multiplexed
address/data bus (AD<7:0>). The TRISD bits are also
overridden.
PORTD can also be configured as an 8-bit wide micro-
processor port (Parallel Slave Port) by setting control
bit, PSPMODE (TRISE<4>). In this mode, the input
buffers are TTL. For additional information, see
Section 12.11 “Parallel Slave Port”.
The PORTD also has the I2C and SPI functionality on
RD4, RD5 and RD6. The pins for SPI are also configu-
rable for open-drain output. Open-drain configuration is
selected by setting bit, SSP2OD (ODCON1<0>).
RD0 has a CTMU functionality. RD1 has the functional-
ity for the Timer5 clock input and Timer7 external clock
gate input.
EXAMPLE 12-4: INITIALIZING PORTD
Note: These pins are configured as digital inputs
on any device Reset.
CLRF PORTD ; Initialize PORTD by
; clearing output
; data latches
CLRF LATD ; Alternate method
; to clear output
; data latches
MOVLW 0CFh ; Value used to
; initialize data
; direction
MOVWF TRISD ; Set RD<3:0> as inputs
; RD<5:4> as outputs
; RD<7:6> as inputs
TABLE 12-7: PORTD FUNCTIONS
Pin Name Function TRIS
Setting I/O I/O
Type Description
RD0/PSP0/
AD0/CTPLS
RD0 0O DIG LATD<0> data output.
1I ST PORTD<0> data input.
PSP0(1) xI/O TTL Parallel Slave Port data.
AD0(2) xI/O TTL External Memory Address/Data 0.
CTPLS xO DIG CTMU pulse generator output.
RD1/PSP1/
AD1/T5CKI/
T7G
RD1 0O DIG LATD<1> data output.
1I ST PORTD<1> data input.
PSP1(1) xI/O TTL Parallel Slave Port data.
AD1(2) xI/O TTL External Memory Address/Data 1.
T5CKI xI ST Timer5 clock input.
T7G xI ST Timer7 external clock gate input.
RD2/PSP2/AD2 RD2 0O DIG LATD<2> data output.
1I ST PORTD<2> data input.
PSP2(1) xI/O TTL Parallel Slave Port data.
AD2(2) xI/O TTL External Memory Address/Data 2.
Legend: O = Output, I = Input, ANA = Analog Signal, DIG = Digital Output, ST = Schmitt Trigger Buffer Input,
I2C = I2C™/SMBus Buffer Input, x = Don’t care (TRIS bit does not affect port direction or is overridden for this option).
Note 1: PSP is available only in Microcontroller mode.
2: This feature is available only on PIC18F8XK22 devices.
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TABLE 12-8: SUMMARY OF REGISTERS ASSOCIATED WITH PORTD
RD3/PSP3/AD3 RD3 0O DIG LATD<3> data output.
1I ST PORTD<3> data input.
PSP3(1) xI/O TTL Parallel Slave Port data.
AD3(2) xI/O TTL External Memory Address/Data 3.
RD4/PSP4/
AD4/SDO2
RD4 0O DIG LATD<4> data output.
1I ST PORTD<4> data input.
PSP4(1) xI/O TTL Parallel Slave Port data.
AD4(2) xI/O TTL External Memory Address/Data 4.
SDO2 0P DOG SPI data output (MSSP module).
RD5/PSP5/
AD5/SDI2/
SDA2
RD5 0O DIG LATD<5> data output.
1I ST PORTD<5> data input.
PSP5(1) xI/O TTL Parallel Slave Port data.
AD5(2) xI/O TTL External Memory Address/Data 5.
SDI2 1I ST SPI data input (MSSP module).
SDA2 0OI
2CI
2C data input (MSSP module). Input type depends on module setting.
RD6/PSP6/
AD6/SCK2/
SCL2
RD6 0O DIG LATD<6> data output.
1I ST PORTD<6> data input.
PSP6(1) xI/O TTL Parallel Slave Port data.
AD6(2) xI/O TTL External Memory Address/Data 6.
SCK2 0O DIG SPI clock output (MSSP module). Takes priority over port data.
1I ST SPI clock input (MSSP module).
SCL2 0ODIGI
2C clock output (MSSP module). Takes priority over port data.
1II
2CI
2C clock input (MSSP module). Input type depends on module
setting.
RD7/PSP7/
AD7/SS2
RD7 0O DIG LATD<7> data output.
1I ST PORTD<7> data input.
PSP7(1) xI/O TTL Parallel Slave Port data.
AD7(2) xI/O TTL External Memory Address/Data 7.
SS2 1I TTL Slave select input for MSSP module.
Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
PORTD RD7 RD6 RD5 RD4 RD3 RD2 RD1 RD0
LATD LATD7 LATD6 LATD5 LATD4 LATD3 LATD2 LATD1 LATD0
TRISD TRISD7 TRISD6 TRISD5 TRISD4 TRISD3 TRISD2 TRISD1 TRISD0
PADCFG1 RDPU REPU RJPU(1) — — RTSECSEL1 RESECSEL0 —
ODCON1 SSP1OD CCP2OD CCP1OD — — — — SSP2OD
Legend: Shaded cells are not used by PORTD.
Note 1: Unimplemented on PIC18F6XK22 devices, read as ‘0’.
TABLE 12-7: PORTD FUNCTIONS (CONTINUED)
Pin Name Function TRIS
Setting I/O I/O
Type Description
Legend: O = Output, I = Input, ANA = Analog Signal, DIG = Digital Output, ST = Schmitt Trigger Buffer Input,
I2C = I2C™/SMBus Buffer Input, x = Don’t care (TRIS bit does not affect port direction or is overridden for this option).
Note 1: PSP is available only in Microcontroller mode.
2: This feature is available only on PIC18F8XK22 devices.
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12.6 PORTE, TRISE and
LATE Registers
PORTE is a eight-bit wide, bidirectional port. The
corresponding Data Direction and Output Latch registers
are TRISE and LATE.
All pins on PORTE are implemented with Schmitt
Trigger input buffers. Each pin is individually
configurable as an input or output. The RE7 pin is also
configurable for open-drain output when ECCP2 is
active on this pin. Open-drain configuration is selected
by setting the CCP2OD control bit (ODCON1<6>)
Each of the PORTE pins has a weak internal pull-up. A
single control bit can turn off all the pull-ups. This is
performed by setting bit, REPU (PADCFG1<6>). The
weak pull-up is automatically turned off when the port
pin is configured as an output. The pull-ups are
disabled on any device Reset.
PORTE is also multiplexed with Enhanced PWM Out-
puts B and C, for ECCP1 and ECCP3, and Outputs B,
C and D, for ECCP2. For all devices, their default
assignments are on PORTE<6:0>.
On 80-pin devices, the multiplexing for the outputs of
ECCP1 and ECCP3 is controlled by the ECCPMX Con-
figuration bit. Clearing this bit reassigns the P1B/P1C
and P3B/P3C outputs to PORTH.
For devices operating in Microcontroller mode, pin, RE7,
can be configured as the alternate peripheral pin for the
ECCP2 module and Enhanced PWM Output 2A. This is
done by clearing the CCP2MX Configuration bit. PORTE
is also multiplexed with the Parallel Slave Port address
lines. RE1 and RE0 are multiplexed with the control
signals, WR and RD.
RE3 can also be configured as the Reference Clock
Output (REFO) from the system clock. For further
details, see Section 3.7 “Reference Clock Output”.
EXAMPLE 12-5: INITIALIZING PORTE
Note: These pins are configured as digital inputs
on any device Reset.
CLRF PORTE ; Initialize PORTE by
; clearing output
; data latches
CLRF LATE ; Alternate method
; to clear output
; data latches
MOVLW 03h ; Value used to
; initialize data
; direction
MOVWF TRISE ; Set RE<1:0> as inputs
; RE<7:2> as outputs
TABLE 12-9: PORTE FUNCTIONS
Pin Name Function TRIS
Setting I/O I/O
Type Description
RE0/P2D/RD/
AD8
RE0 0O DIG LATE<0> data output.
1I ST PORTE<0> data input.
P2D 0O — ECCP2 PWM Output D.
May be configured for tri-state during Enhanced PWM shutdown events.
RD xO DIG Parallel Slave Port read strobe pin.
xI TTL Parallel Slave Port read pin.
AD8(2) xO DIG External memory interface, Data Bit 8 output.
xI TTL External memory interface, Data Bit 8 input.
RE1/P2C/WR/
AD9
RE1 0O DIG LATE<1> data output.
1I ST PORTE<1> data input.
P2C 0 O — ECCP2 PWM Output C.
May be configured for tri-state during Enhanced PWM shutdown events.
WR xO DIG Parallel Slave Port write strobe pin.
xI TTL Parallel Slave Port write pin.
AD9(2) xO DIG External memory interface, Data Bit 9 output.
xI TTL External memory interface, Data Bit 9 input.
Legend: O = Output, I = Input, ANA = Analog Signal, DIG = Digital Output, ST = Schmitt Trigger Buffer Input,
x = Don’t care (TRIS bit does not affect port direction or is overridden for this option).
Note 1: Alternate assignment for ECCP2 when the CCP2MX Configuration bit is cleared and in Microcontroller mode.
2: This feature is only available on PIC18F8XKXX devices.
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RE2/P2B/
CCP10/CS/
AD10
RE2 0O DIG LATE<2> data output.
1I ST PORTE<2> data input.
P2B 0O — ECCP2 PWM Output B.
May be configured for tri-state during Enhanced PWM shutdown events.
CCP10 1I/O ST Capture 10 input/Compare 10 output/PWM10 output.
CS xI TTL Parallel Slave Port chip select.
AD10(2) xO DIG External memory interface, Address/Data Bit 10 output.
xI TTL External memory interface, Data Bit 10 input.
RE3/P3C/
CCP9/REFO/
AD11
RE3 0O DIG LATE<3> data output.
1I ST PORTE<3> data input.
P3C 0O — ECCP3 PWM Output C.
May be configured for tri-state during Enhanced PWM shutdown events.
CCP9 0O DIG CCP9 Compare/PWM output. Takes priority over port data.
1I ST CCP9 capture input.
REFO xO DIG Reference output clock.
AD11(2) xO DIG External memory interface, Address/Data Bit 11 output.
xI TTL External memory interface, Data Bit 11 input.
RE4/P3B/
CCP8/AD12
RE4 0O DIG LATE<4> data output.
1I ST PORTE<4> data input.
P3B 0O — ECCP3 PWM Output B.
May be configured for tri-state during Enhanced PWM shutdown events.
CCP8 0O DIG CCP8 compare/PWM output. Takes priority over port data.
1I ST CCP8 capture input.
AD12(2) xO DIG External memory interface, Address/Data Bit 12 output.
xI TTL External memory interface, Data Bit 12 input.
RE5/P1C/
CCP7/AD13
RE5 0O DIG LATE<5> data output.
1I ST PORTE<5> data input.
P1C 0O — ECCP1 PWM Output C.
May be configured for tri-state during Enhanced PWM shutdown events.
CCP7 0O DIG CCP7 compare/PWM output. Takes priority over port data.
1I ST CCP7 capture input.
AD13(2) xO DIG External memory interface, Address/Data Bit 13 output.
xI TTL External memory interface, Data bit 13 input.
RE6/P1B/
CCP6/AD14
RE6 0O DIG LATE<6> data output.
1I ST PORTE<6> data input.
P1B 0O — ECCP1 PWM Output B.
May be configured for tri-state during Enhanced PWM shutdown events.
CCP6 0O DIG CCP6 compare/PWM output. Takes priority over port data.
1I ST CCP9 capture input.
AD14(2) xO DIG External memory interface, Address/Data Bit 14 output.
xI TTL External memory interface, Data Bit 14 input.
TABLE 12-9: PORTE FUNCTIONS (CONTINUED)
Pin Name Function TRIS
Setting I/O I/O
Type Description
Legend: O = Output, I = Input, ANA = Analog Signal, DIG = Digital Output, ST = Schmitt Trigger Buffer Input,
x = Don’t care (TRIS bit does not affect port direction or is overridden for this option).
Note 1: Alternate assignment for ECCP2 when the CCP2MX Configuration bit is cleared and in Microcontroller mode.
2: This feature is only available on PIC18F8XKXX devices.
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TABLE 12-10: SUMMARY OF REGISTERS ASSOCIATED WITH PORTE
RE7/ECCP2/
P2A/AD15
RE7 0O DIG LATE<7> data output.
1I ST PORTE<7> data input.
ECCP2(1) 0O DIG ECCP2 compare/PWM output; takes priority over port data.
1I ST ECCP2 Capture input.
P2A 0O — ECCP2 PWM Output A.
May be configured for tri-state during Enhanced PWM shutdown event.
AD15(2) xO DIG External memory interface, Address/Data Bit 15 output.
xI TTL External memory interface, Data Bit 15 input.
Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
PORTE RE7 RE6 RE5 RE4 RE3 RE2 RE1 RE0
LATE LATE7 LATE6 LATE5 LATE4 LATE3 LATE2 LATE1 LATE0
TRISE TRISE7 TRISE6 TRISE5 TRISE4 TRISE3 TRISE2 TRISE1 TRISE0
PADCFG1 RDPU REPU RJPU(2) — — RTSECSEL1 RTSECSEL0 —
ODCON1 SSP1OD CCP2OD CCP1OD — — — — SSP2OD
ODCON2 CCP10OD(1) CCP9OD(1) CCP8OD CCP7OD CCP6OD CCP5OD CCP4OD CCP3OD
Legend: Shaded cells are not used by PORTE.
Note 1: Unimplemented on PIC18FX5K22 devices, read as ‘0’.
2: Unimplemented on 64-pin devices (PIC18F6XK22), read as ‘0’.
TABLE 12-9: PORTE FUNCTIONS (CONTINUED)
Pin Name Function TRIS
Setting I/O I/O
Type Description
Legend: O = Output, I = Input, ANA = Analog Signal, DIG = Digital Output, ST = Schmitt Trigger Buffer Input,
x = Don’t care (TRIS bit does not affect port direction or is overridden for this option).
Note 1: Alternate assignment for ECCP2 when the CCP2MX Configuration bit is cleared and in Microcontroller mode.
2: This feature is only available on PIC18F8XKXX devices.
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12.7 PORTF, LATF and TRISF Registers
PORTF is a 7-bit wide, bidirectional port. The
corresponding Data Direction and Output Latch registers
are TRISF and LATF. All pins on PORTF are
implemented with Schmitt Trigger input buffers. Each pin
is individually configurable as an input or output.
Pins, RF1 through RF6, may be used as comparator
inputs or outputs by setting the appropriate bits in the
CMCON register. To use RF<7:1> as digital inputs, it is
also necessary to turn off the comparators.
EXAMPLE 12-6: INITIALI ZING PORTF
Note 1: On device Resets, pins, RF<7:1>, are
configured as analog inputs and are read
as ‘0’.
2: To configure PORTF as a digital I/O, turn
off the comparators and clear ANCON1
and ANCON2 to digital.
CLRF PORTF ; Initialize PORTF by
; clearing output
; data latches
CLRF LATF ; Alternate method
; to clear output
; data latches
BANKSEL ANCON1 ; Select bank with ANCON1 register
MOVLW 1Fh ; Make AN6, AN7 and AN5 digital
MOVWF ANCON1 ;
MOVLW 0Fh ; Make AN8, AN9, AN10 and AN11
digital
MOVWF ANCON ; Set PORTF as digital I/O
BANKSEL TRISF ; Select bank with TRISF register
MOVLW 0CEh ; Value used to
; initialize data
; direction
MOVWF TRISF ; Set RF3:RF1 as inputs
; RF5:RF4 as outputs
; RF7:RF6 as inputs
TABLE 12-11: PORTF FUNCTIONS
Pin Name Function TRIS
Setting I/O I/O
Type Description
RF1/AN6/C2OUT/
CTDIN
RF1 0O DIG LATF<1> data output; not affected by analog input.
1I ST PORTF<1> data input; disabled when analog input is enabled.
AN6 1I ANA A/D Input Channel 6. Default configuration on POR.
C2OUT 0O DIG Comparator 2 output; takes priority over port data.
CTDIN 1I ST CTMU pulse delay input.
RF2/AN7/C1OUT RF2 0O DIG LATF<2> data output; not affected by analog input.
1I ST PORTF<2> data input; disabled when analog input is enabled.
AN7 1I ANA A/D Input Channel 7. Default configuration on POR.
C1OUT 0O DIG Comparator 1 output; takes priority over port data.
RF3/AN8/C2INB/
CTMUI
RF3 0O DIG LATF<3> data output; not affected by analog input.
1I ST PORTF<3> data input; disabled when analog input is enabled.
AN8 1I ANA A/D Input Channel 8 and Comparator C2+ input. Default input
configuration on POR; not affected by analog output.
C2INB 1I ANA Comparator 2 Input B.
CTMUI xO — CTMU pulse generator charger for the C2INB comparator input.
RF4/AN9/C2INA RF4 0O DIG LATF<4> data output; not affected by analog input.
1I ST PORTF<4> data input; disabled when analog input is enabled.
AN9 1I ANA A/D Input Channel 9 and Comparator C2- input. Default input
configuration on POR; does not affect digital output.
C2INA 1I ANA Comparator 2 Input A.
RF5/AN10/CVREF/
C1INB
RF5 0O DIG LATF<5> data output; not affected by analog input. Disabled when
CVREF output is enabled.
1I ST PORTF<5> data input; disabled when analog input is enabled.
Disabled when CVREF output is enabled.
AN10 1I ANA A/D Input Channel 10 and Comparator C1+ input. Default input
configuration on POR.
CVREF xO ANA Comparator voltage reference output. Enabling this feature disables
digital I/O.
C1INB 1I ANA Comparator 1 Input B.
Legend: O = Output, I = Input, ANA = Analog Signal, DIG = Digital Output, ST = Schmitt Trigger Buffer Input,
TTL = TTL Buffer Input, x = Don’t care (TRIS bit does not affect port direction or is overridden for this option).
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DS39960C-page 182 2011 Microchip Technology Inc.
TABLE 12-12: SUMMARY OF REGISTERS ASSOCIATED WITH PORTF
RF6/AN11/C1INA RF6 0O DIG LATF<6> data output; not affected by analog input.
1I ST PORTF<6> data input; disabled when analog input is enabled.
AN11 1I ANA A/D Input Channel 11 and Comparator C1- input. Default input
configuration on POR; does not affect digital output.
C1INA 1I ANA Comparator 1 Input A.
RF7/AN5/SS1 RF7 0O DIG LATF<7> data output; not affected by analog input.
1I ST PORTF<7> data input; disabled when analog input is enabled.
AN5 1I ANA A/D Input Channel 5. Default configuration on POR.
SS1 1I TTL Slave select input for MSSP module.
Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
PORTF RF7 RF6 RF5 RF4 RF3 RF2 RF1 —
LATF LATF7 LATF6 LATF5 LATF4 LATF3 LATF2 LATF1 —
TRISF TRISF7 TRISF6 TRISF5 TRISF4 TRISF3 TRISF2 TRISF1 —
ANCON0 ANSEL7 ANSEL6 ANSEL5 ANSEL4 ANSEL3 ANSEL2 ANSEL1 ANSEL0
ANCON1 ANSEL15 ANSEL14 ANSEL13 ANSEL12 ANSEL11 ANSEL10 ANSEL9 ANSEL8
Legend: — = unimplemented, read as ‘0’. Shaded cells are not used by PORTF.
TABLE 12-11: PORTF FUNCTIONS (CONTINUED)
Pin Name Function TRIS
Setting I/O I/O
Type Description
Legend: O = Output, I = Input, ANA = Analog Signal, DIG = Digital Output, ST = Schmitt Trigger Buffer Input,
TTL = TTL Buffer Input, x = Don’t care (TRIS bit does not affect port direction or is overridden for this option).
2011 Microchip Technology Inc. DS39960C-page 183
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12.8 PORTG, TRISG and
LATG Registers
PORTG is a 5-bit wide, bidirectional port. The
corresponding Data Direction and Output Latch registers
are TRISG and LATG.
PORTG is multiplexed with AUSART and CCP, ECCP,
Analog, Comparator, RTCC and Timer input functions
(Table 12-13). When operating as I/O, all PORTG pins
have Schmitt Trigger input buffers. The open-drain
functionality for the CCPx and UART can be configured
using ODCONx.
When enabling peripheral functions, care should be
taken in defining TRIS bits for each PORTG pin. Some
peripherals override the TRIS bit to make a pin an
output, while other peripherals override the TRIS bit to
make a pin an input. The user should refer to the
corresponding peripheral section for the correct TRIS bit
settings. The pin override value is not loaded into the
TRIS register. This allows read-modify-write of the TRIS
register without concern due to peripheral overrides.
EXAMPLE 12-7: INITIALIZING PORTG
CLRF PORTG ; Initialize PORTG by
; clearing output
; data latches
BCF CM1CON, CON ; disable
; comparator 1
CLRF LATG ; Alternate method
; to clear output
; data latches
BANKSEL ANCON2 ; Select bank with ACON2 register
MOVLW 0F0h ; make AN16 to AN19
; digital
MOVWF ANCON2
BANKSEL TRISG ; Select bank with TRISG register
MOVLW 04h ; Value used to
; initialize data
; direction
MOVWF TRISG ; Set RG1:RG0 as
; outputs
; RG2 as input
; RG4:RG3 as inputs
TABLE 12-13: PORTG FUNCTIONS
Pin Name Function TRIS
Setting I/O I/O
Type Description
RG0/ECCP3/
P3A
RG0 0O DIG LATG<0> data output.
1I ST PORTG<0> data input.
ECCP3 0O DIG ECCP3 compare output and ECCP3 PWM output. Takes priority over
port data.
1I ST ECCP3 capture input.
P3A 0O — ECCP3 PWM Output A.
May be configured for tri-state during Enhanced PWM shutdown
events.
RG1/TX2/CK2/
AN19/C3OUT
RG1 0O DIG LATG<1> data output.
1I ST PORTG<1> data input.
TX2 1O DIG Synchronous serial data output (EUSART module); takes priority over
port data.
CK2 1O DIG Synchronous serial data input (EUSART module); user must configure
as an input.
1I ST Synchronous serial clock input (EUSART module).
AN19 1I ANA A/D Input Channel 19.
Default input configuration on POR. Does not affect digital output.
C3OUT xO DIG Comparator 3 output.
Legend: O = Output, I = Input, ANA = Analog Signal, DIG = Digital Output, ST = Schmitt Trigger Buffer Input,
x = Don’t care (TRIS bit does not affect port direction or is overridden for this option).
PIC18F87K22 FAMILY
DS39960C-page 184 2011 Microchip Technology Inc.
TABLE 12-14: SUMMARY OF REGISTERS ASSOCIATED WITH PORTG
RG2/RX2/DT2/
AN18/C3INA
RG2 0O DIG LATG<2> data output.
1I ST PORTG<2> data input.
RX2 1I ST Asynchronous serial receive data input (EUSART module).
DT2 1O DIG Synchronous serial data output (EUSART module); takes priority over
port data.
1I ST Synchronous serial data input (EUSART module); user must configure
as an input.
AN18 1I ANA A/D Input Channel 18.
Default input configuration on POR. Does not affect digital output.
C3INA xI ANA Comparator 3 Input A.
RG3/CCP4/AN17/
P3D/C3INB
RG3 0O DIG LATG<3> data output.
1I ST PORTG<3> data input.
CCP4 0O DIG CCP4 compare/PWM output. Takes priority over port data.
1I ST CCP4 capture input.
AN17 1I ANA A/D Input Channel 17.
Default input configuration on POR. Does not affect digital output.
P3D 0O — ECCP3 PWM Output D.
May be configured for tri-state during enhanced PWM.
C3INB xI ANA Comparator 3 Input B.
RG4/RTCC/
T7CKI/T5G/
CCP5/AN16/
P1D/C3INC
RG4 0O DIG LATG<4> data output.
1I ST PORTG<4> data input.
RTCC xO DIG RTCC output.
T7CKI xI ST Timer7 clock input.
T5G xI ST Timer5 external clock gate input.
CCP5 0O DIG CCP5 compare/PWM output. Takes priority over port data.
1I ST CCP5 capture input.
AN16 1I ANA A/D Input Channel 17.
Default input configuration on POR. Does not affect digital output.
P1D 0O — ECCP1 PWM Output D.
May be configured for tri-state during Enhanced PWM.
C3INC xI ANA Comparator 3 Input C.
Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
PORTG ——RG5
(2) RG4 RG3 RG2 RG1 RG0
TRISG — — — TRISG4 TRISG3 TRISG2 TRISG1 TRISG0
ANCON2 ANSEL23 ANSEL22 ANSEL21 ANSEL20 ANSEL19 ANSEL18 ANSEL17 ANSEL16
ODCON1 SSP1OD CCP2OD CCP1OD — — — — SSP2OD
ODCON2 CCP10OD(1) CCP9OD(1) CCP8OD CCP7OD CCP6OD CCP5OD CCP4OD CCP3OD
ODCON3 U2OD U1OD — — — — — CTMUDS
Legend: — = unimplemented, read as ‘0’. Shaded cells are not used by PORTG.
Note 1: Unimplemented on PIC18FX5K22 devices, read as ‘0’.
2: Bit is available when Master Clear is disabled (MCLRE = 0). When MCLRE is set, the bit is unimplemented.
TABLE 12-13: PORTG FUNCTIONS (CONTINUED)
Pin Name Function TRIS
Setting I/O I/O
Type Description
Legend: O = Output, I = Input, ANA = Analog Signal, DIG = Digital Output, ST = Schmitt Trigger Buffer Input,
x = Don’t care (TRIS bit does not affect port direction or is overridden for this option).
2011 Microchip Technology Inc. DS39960C-page 185
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12.9 PORTH, LATH and
TRISH Registers
PORTH is an 8-bit wide, bidirectional I/O port. The
corresponding Data Direction and Output Latch registers
are TRISH and LATH.
All pins on PORTH are implemented with Schmitt
Trigger input buffers. Each pin is individually
configurable as an input or output.
EXAMPLE 12-8: INITIA LIZING PORTH
Note: PORTH is available only on the 80-pin
devices.
CLRF PORTH ; Initialize PORTH by
; clearing output
; data latches
CLRF LATH ; Alternate method
; to clear output
; data latches
BANKSEL ANCON2 ; Select bank wi th ANCON 2 registe r
MOVLW 0Fh ; Configure PORTH as
MOVWF ANCON2 ; digital I/O
MOVLW 0Fh ; Configure PORTH as
MOVWF ANCON1 ; digital I/O
BANKSEL TRISH ; Select bank with TRISH register
MOVLW 0CFh ; Value used to
; initialize data
; direction
MOVWF TRISH ; Set RH3:RH0 as inputs
; RH5:RH4 as outputs
; RH7:RH6 as inputs
TABLE 12-15: PORTH FUNCTIONS
Pin Name Function TRIS
Setting I/O I/O
Type Description
RH0/AN23/A16 RH0 0O DIG LATH<0> data output.
1I ST PORTH<0> data input.
AN23 1I ANA A/D Input Channel 23.
Default input configuration on POR. Does not affect digital input.
A16 xO DIG External memory interface, address line 16. Takes priority over port
data.
RH1/AN22/A17 RH1 0O DIG LATH<1> data output.
1I ST PORTH<1> data input.
AN22 1I ANA A/D Input Channel 22.
Default input configuration on POR. Does not affect digital input.
A17 xO DIG External memory interface, address line 17. Takes priority over port
data.
RH2/AN21/A18 RH2 0O DIG LATH<2> data output.
1I ST PORTH<2> data input.
AN21 1I ANA A/D Input Channel 21.
Default input configuration on POR. Does not affect digital input.
A18 xO DIG External memory interface, address line 18. Takes priority over port
data.
RH3/AN20/A19 RH3 0O DIG LATH<3> data output.
1I ST PORTH<3> data input.
AN20 1I ANA A/D Input Channel 20.
Default input configuration on POR. Does not affect digital input.
A19 xO DIG External memory interface, address line 19. Takes priority over port
data.
Legend: O = Output, I = Input, ANA = Analog Signal, DIG = Digital Output, ST = Schmitt Trigger Buffer Input,
x = Don’t care (TRIS bit does not affect port direction or is overridden for this option).
PIC18F87K22 FAMILY
DS39960C-page 186 2011 Microchip Technology Inc.
RH4/CCP9/
P3C/AN12/
C2INC
RH4 0O DIG LATH<4> data output.
1I ST PORTH<4> data input.
CCP9 0O DIG CCP9 compare/PWM output. Takes priority over port data.
1I ST CCP9 capture input.
P3C 0O — ECCP3 PWM Output C.
May be configured for tri-state during Enhanced PWM.
AN12 1I ANA A/D Input Channel 12.
Default input configuration on POR. Does not affect digital input.
C2INC xI ANA Comparator 2 Input C.
RH5/CCP8/
P3B/AN13/
C2IND
RH5 0O DIG LATH<5> data output.
1I ST PORTH<5> data input.
CCP8 0O DIG CCP8 compare/PWM output. Takes priority over port data.
1I ST CCP8 capture input.
P3B 0O — ECCP3 PWM Output B.
May be configured for tri-state during Enhanced PWM.
AN13 1I ANA A/D Input Channel 13.
Default input configuration on POR. Does not affect digital input.
C2IND xI ANA Comparator 2 Input D.
RH6/CCP7/
P1C/AN14/
C1INC
RH6 0O DIG LATH<6> data output.
1I ST PORTH<6> data input.
CCP7 0O DIG CCP7 compare/PWM output. Takes priority over port data.
1I ST CCP7 capture input.
P1C 0O — ECCP1 PWM Output C.
May be configured for tri-state during Enhanced PWM.
AN14 1I ANA A/D Input Channel 14.
Default input configuration on POR. Does not affect digital input.
C1INC xI ANA Comparator 1 Input C.
RH7/CCP6/
P1B/AN15
RH7 0O DIG LATH<7> data output.
1I ST PORTH<7> data input.
CCP6 0O DIG CCP6 compare/PWM output. Takes priority over port data.
1I ST CCP6 capture input.
P1B 0O — ECCP1 PWM Output B.
May be configured for tri-state during Enhanced PWM.
AN15 1I ANA A/D Input Channel 15.
Default input configuration on POR. Does not affect digital input.
TABLE 12-15: PORTH FUNCTIONS (CONTINUED)
Pin Name Function TRIS
Setting I/O I/O
Type Description
Legend: O = Output, I = Input, ANA = Analog Signal, DIG = Digital Output, ST = Schmitt Trigger Buffer Input,
x = Don’t care (TRIS bit does not affect port direction or is overridden for this option).
2011 Microchip Technology Inc. DS39960C-page 187
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TABLE 12-16: SUMMARY OF REGISTERS ASSOCIATED WITH PORTH
12.10 PORTJ, TRISJ and
LATJ Registers
PORTJ is an 8-bit wide, bidirectional port. The
corresponding Data Direction and Output Latch registers
are TRISJ and LATJ.
All pins on PORTJ are implemented with Schmitt
Trigger input buffers. Each pin is individually
configurable as an input or output.
When the external memory interface is enabled, all of
the PORTJ pins function as control outputs for the inter-
face. This occurs automatically when the interface is
enabled by clearing the EBDIS control bit
(MEMCON<7>). The TRISJ bits are also overridden.
Each of the PORTJ pins has a weak internal pull-up.
The pull-ups are provided to keep the inputs at a known
state for the external memory interface while powering
up. A single control bit can turn off all the pull-ups. This
is performed by clearing bit, RJPU (PADCFG1<5>).
The weak pull-up is automatically turned off when the
port pin is configured as an output. The pull-ups are
disabled on any device Reset.
EXAMPLE 12-9: INITIALIZING PORTJ
Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
PORTH(1) RH7 RH6 RH5 RH4 RH3 RH2 RH1 RH0
LATH(1) LATH7 LATH6 LATH5 LATH4 LATH3 LATH2 LATH1 LATH0
TRISH(1) TRISH7 TRISH6 TRISH5 TRISH4 TRISH3 TRISH2 TRISH1 TRISH0
ANCON1 ANSEL15 ANSEL14 ANSEL13 ANSEL12 ANSEL11 ANSEL10 ANSEL9 ANSEL8
ANCON2 ANSEL23 ANSEL22 ANSEL21 ANSEL20 ANSEL19 ANSEL18 ANSEL17 ANSEL16
ODCON2 CCP10OD(2) CCP9OD(2) CCP8OD CCP7OD CCP6OD CCP5OD CCP4OD CCP3OD
Note 1: Unimplemented on 64-pin devices (PIC18F6XK22), read as ‘0’.
2: Unimplemented on PIC18FX5K22 devices, read as ‘0’.
Note: PORTJ is available only on 80-pin devices.
Note: These pins are configured as digital inputs
on any device Reset.
CLRF PORTJ ; Initialize PORTJ by
; clearing output latches
CLRF LATJ ; Alternate method
; to clear output latches
MOVLW 0CFh ; Value used to
; initialize data
; direction
MOVWF TRISJ ; Set RJ3:RJ0 as inputs
; RJ5:RJ4 as output
; RJ7:RJ6 as inputs
PIC18F87K22 FAMILY
DS39960C-page 188 2011 Microchip Technology Inc.
TABLE 12-17: PORTJ FUNCTIONS
TABLE 12-18: SUMMARY OF REGISTERS ASSOCIATED WITH PORTJ
Pin Name Function TRIS
Setting I/O I/O
Type Description
RJ0/ALE RJ0 0O DIG LATJ<0> data output.
1I ST PORTJ<0> data input.
ALE xO DIG External memory interface address latch enable control output. Takes
priority over digital I/O.
RJ1/OE RJ1 0O DIG LATJ<1> data output.
1I ST PORTJ<1> data input.
OE xO DIG External memory interface output enable control output. Takes priority
over digital I/O.
RJ2/WRL RJ2 0O DIG LATJ<2> data output.
1I ST PORTJ<2> data input.
WRL xO DIG External Memory Bus write low byte control. Takes priority over
digital I/O.
RJ3/WRH RJ3 0O DIG LATJ<3> data output.
1I ST PORTJ<3> data input.
WRH xO DIG External memory interface write high-byte control. Takes priority over
digital I/O.
RJ4/BA0 RJ4 0O DIG LATJ<4> data output.
1I ST PORTJ<4> data input.
BA0 xO DIG External memory interface byte address 0 control output. Takes
priority over digital I/O.
RJ5/CE RJ5 0O DIG LATJ<5> data output.
1I ST PORTJ<5> data input.
CE xO DIG External memory interface chip enable control output. Takes priority
over digital I/O.
RJ6/LB RJ6 0O DIG LATJ<6> data output.
1I ST PORTJ<6> data input.
LB xO DIG External memory interface lower byte enable control output. Takes
priority over digital I/O.
RJ7/UB RJ7 0O DIG LATJ<7> data output.
1I ST PORTJ<7> data input.
UB xO DIG External memory interface upper byte enable control output. Takes
priority over digital I/O.
Legend: O = Output, I = Input, ANA = Analog Signal, DIG = Digital Output, ST = Schmitt Trigger Buffer Input,
x = Don’t care (TRIS bit does not affect port direction or is overridden for this option).
Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
PORTJ(1) RJ7 RJ6 RJ5 RJ4 RJ3 RJ2 RJ1 RJ0
LATJ(1) LATJ7 LATJ6 LATJ5 LATJ4 LATJ3 LATJ2 LATJ1 LATJ0
TRISJ(1) TRISJ7 TRISJ6 TRISJ5 TRISJ4 TRISJ3 TRISJ2 TRISJ1 TRISJ0
PADCFG1 RDPU REPU RJPU(1) — — RTSECSEL1 RTSECSEL0 —
Legend: Shaded cells are not used by PORTJ.
Note 1: Unimplemented on 64-pin devices (PIC18F6XK22), read as ‘0’.
2011 Microchip Technology Inc. DS39960C-page 189
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12.11 Parallel Slave Port
PORTD can function as an 8-bit-wide Parallel Slave
Port (PSP), or microprocessor port, when control bit,
PSPMODE (PSPCON<4>), is set. The port is asyn-
chronously readable and writable by the external world
through the RD control input pin (RE0/P2D/RD/AD8)
and WR control input pin (RE1/P2C/WR/AD9).
The PSP can directly interface to an 8-bit micro-
processor data bus. The external microprocessor can
read or write the PORTD latch as an eight-bit latch.
Setting bit, PSPMODE, enables port pin,
RE0/P2D/RD/AD8, to be the RD input,
RE1/P2C/WR/AD9 to be the WR input and
RE2/P2B/CCP10/CS/AD10 to be the CS (Chip Select)
input. For this functionality, the corresponding data
direction bits of the TRISE register (TRISE<2:0>) must
be configured as inputs (= 111).
A write to the PSP occurs when both the CS and WR
lines are first detected low and ends when either are
detected high. The PSPIF and IBF flag bits (PIR1<7>
and PSPCON<7>, respectively) are set when the write
ends.
A read from the PSP occurs when both the CS and RD
lines are first detected low. The data in PORTD is read
out and the OBF bit (PSPCON<6>) is set. If the user
writes new data to PORTD to set OBF, the data is
immediately read out, but the OBF bit is not set.
When either the CS or RD line is detected high, the
PORTD pins return to the input state and the PSPIF bit
is set. User applications should wait for PSPIF to be set
before servicing the PSP. When this happens, the IBF
and OBF bits can be polled and the appropriate action
taken.
The timing for the control signals in Write and Read
modes is shown in Figure 12-4 and Figure 12-5,
respectively.
FIGURE 12-3: PORTD AND PORTE
BLOCK DIAGRAM
(PARALLEL SLAVE PORT)
Note: The Parallel Slave Port is available only in
Microcontroller mode.
Data Bus
WR LATD
RDx
QD
CK
EN
QD
EN
RD PORTD
Pin
One Bit of PORTD
Set Interrupt Flag
PSPIF (PIR1<7>)
Read
Chip Select
Write
RD
CS
WR
Note: The I/O pin has protection diodes to VDD and VSS.
TTL
TTL
TTL
TTL
or
PORTD
RD LATD
Data Latch
TRIS Latch
PIC18F87K22 FAMILY
DS39960C-page 190 2011 Microchip Technology Inc.
FIGURE 12-4: PARALLEL SLAVE PORT WRITE WAVEFORMS
REGISTER 12-5: PSPCON: PARALLEL SLAVE PORT CONTROL REGISTER
R-0 R-0 R/W-0 R/W-0 U-0 U-0 U-0 U-0
IBF OBF IBOV PSPMODE — — — —
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 IBF: Input Buffer Full Status bit
1 = A word has been received and is waiting to be read by the CPU
0 = No word has been received
bit 6 OBF: Output Buffer Full Status bit
1 = The output buffer still holds a previously written word
0 = The output buffer has been read
bit 5 IBOV: Input Buffer Overflow Detect bit
1 = A write occurred when a previously input word had not been read (must be cleared in software)
0 = No overflow occurred
bit 4 PSPMODE: Parallel Slave Port Mode Select bit
1 = Parallel Slave Port mode
0 = General Purpose I/O mode
bit 3-0 Unimplemented: Read as ‘0’
Q1 Q2 Q3 Q4
CS
Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4
WR
RD
IBF
OBF
PSPIF
PORTD<7:0>
2011 Microchip Technology Inc. DS39960C-page 191
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FIGURE 12-5: PARALLEL SLAVE PORT READ WAVEFORMS
TABLE 12-19: REGISTERS ASSOCIATED WITH PARALLEL SLAVE PORT
Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
PORTD RD7 RD6 RD5 RD4 RD3 RD2 RD1 RD0
LATD LATD7 LATD6 LATD5 LATD4 LATD3 LATD2 LATD1 LATD0
TRISD TRISD7 TRISD6 TRISD5 TRISD4 TRISD3 TRISD2 TRISD1 TRISD0
PORTE RE7 RE6 RE5 RE4 RE3 RE2 RE1 RE0
LATE LATE7 LATE6 LATE5 LATE4 LATE3 LATE2 LATE1 LATE0
TRISE TRISE7 TRISE6 TRISE5 TRISE4 TRISE3 TRISE2 TRISE1 TRISE0
PSPCON IBF OBF IBOV PSPMODE — — — —
INTCON GIE/GIEH PEIE/GIEL TMR0IE INT0IE RBIE TMR0IF INT0IF RBIF
PIR1 PSPIF ADIF RC1IF TX1IF SSP1IF TMR1GIF TMR2IF TMR1IF
PIE1 PSPIE ADIE RC1IE TX1IE SSP1IE TMR1GIE TMR2IE TMR1IE
IPR1 PSPIP ADIP RC1IP TX1IP SSP1IP TMR1GIP TMR2IP TMR1IP
PMD1 PSPMD CTMUMD RTCCMD TMR4MD TMR3MD TMR2MD TMR1MD EMBDM
Legend: — = unimplemented, read as ‘0’. Shaded cells are not used by the Parallel Slave Port.
Q1 Q2 Q3 Q4
CS
Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4
WR
IBF
PSPIF
RD
OBF
PORTD<7:0>
PIC18F87K22 FAMILY
DS39960C-page 192 2011 Microchip Technology Inc.
NOTES:
2011 Microchip Technology Inc. DS39960C-page 193
PIC18F87K22 FAMILY
13.0 TIMER0 MODULE
The Timer0 module incorporates the following features:
• Software-selectable operation as a timer or
counter in both 8-bit or 16-bit modes
• Readable and writable registers
• Dedicated 8-bit, software programmable
prescaler
• Selectable clock source (internal or external)
• Edge select for external clock
• Interrupt-on-overflow
The T0CON register (Register 13-1) controls all
aspects of the module’s operation, including the
prescale selection. It is both readable and writable.
Figure 13-1 provides a simplified block diagram of the
Timer0 module in 8-bit mode. Figure 13-2 provides a
simplified block diagram of the Timer0 module in 16-bit
mode.
REGISTER 13-1: T0CON: TIMER0 CONTROL REGISTER
R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1
TMR0ON T08BIT T0CS T0SE PSA T0PS2 T0PS1 T0PS0
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 TMR0ON: Timer0 On/Off Control bit
1 = Enables Timer0
0 = Stops Timer0
bit 6 T08BIT: Timer0 8-Bit/16-Bit Control bit
1 = Timer0 is configured as an 8-bit timer/counter
0 = Timer0 is configured as a 16-bit timer/counter
bit 5 T0CS: Timer0 Clock Source Select bit
1 = Transition on T0CKI pin input edge
0 = Internal clock (FOSC/4)
bit 4 T0SE: Timer0 Source Edge Select bit
1 = Increment on high-to-low transition on T0CKI pin
0 = Increment on low-to-high transition on T0CKI pin
bit 3 PSA: Timer0 Prescaler Assignment bit
1 = Timer0 prescaler is not assigned. Timer0 clock input bypasses prescaler
0 = Timer0 prescaler is assigned. Timer0 clock input comes from prescaler output
bit 2-0 T0PS<2:0>: Timer0 Prescaler Select bits
111 = 1:256 Prescale value
110 = 1:128 Prescale value
101 = 1:64 Prescale value
100 = 1:32 Prescale value
011 = 1:16 Prescale value
010 = 1:8 Prescale value
001 = 1:4 Prescale value
000 = 1:2 Prescale value
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13.1 Timer0 Operation
Timer0 can operate as either a timer or a counter. The
mode is selected with the T0CS bit (T0CON<5>). In
Timer mode (T0CS = 0), the module increments on
every clock by default unless a different prescaler value
is selected (see Section 13.3 “Prescaler”). If the
TMR0 register is written to, the increment is inhibited
for the following two instruction cycles. The user can
work around this by writing an adjusted value to the
TMR0 register.
The Counter mode is selected by setting the T0CS bit
(= 1). In this mode, Timer0 increments either on every
rising edge or falling edge of the T0CKI pin. The
incrementing edge is determined by the Timer0 Source
Edge Select bit, T0SE (T0CON<4>); clearing this bit
selects the rising edge. Restrictions on the external
clock input are discussed below.
An external clock source can be used to drive Timer0;
however, it must meet certain requirements to ensure
that the external clock can be synchronized with the
internal phase clock (T
OSC). There is a delay between
synchronization and the onset of incrementing the
timer/counter.
13.2 Timer0 Re ads and Writes in 16-Bit
Mode
TMR0H is not the actual high byte of Timer0 in 16-bit
mode. It is actually a buffered version of the real high
byte of Timer0, which is not directly readable nor
writable. (See Figure 13-2.) TMR0H is updated with the
contents of the high byte of Timer0 during a read of
TMR0L. This provides the ability to read all 16 bits of
Timer0 without having to verify that the read of the high
and low byte were valid, due to a rollover between
successive reads of the high and low byte.
Similarly, a write to the high byte of Timer0 must also
take place through the TMR0H Buffer register. The high
byte is updated with the contents of TMR0H when a
write occurs to TMR0L. This allows all 16 bits of Timer0
to be updated at once.
FIGURE 13-1: TIMER0 BLOCK DIAGRAM (8-BIT MODE)
FIGURE 13-2: TIMER0 BLOCK DIAGRAM (16-BIT MODE)
Note: Upon Reset, Timer0 is enabled in 8-bit mode with clock input from T0CKI max. prescale.
T0CKI Pin
T0SE
0
1
1
0
T0CS
FOSC/4
Programmable
Prescaler
Sync with
Internal
Clocks
TMR0L
(2 TCY Delay)
Internal Data Bus
PSA
T0PS<2:0>
Set
TMR0IF
on Overflow
38
8
Note: Upon Reset, Timer0 is enabled in 8-bit mode with clock input from T0CKI max. prescale.
T0CKI Pin
T0SE
0
1
1
0
T0CS
FOSC/4
Sync with
Internal
Clocks
TMR0L
(2 TCY Delay)
Internal Data Bus
8
PSA
T0PS<2:0>
Set
TMR0IF
on Overflow
3
TMR0
TMR0H
High Byte
88
8
Read TMR0L
Write TMR0L
8
Programmable
Prescaler
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13.3 Prescaler
An 8-bit counter is available as a prescaler for the Timer0
module. The prescaler is not directly readable or writable.
Its value is set by the PSA and T0PS<2:0> bits
(T0CON<3:0>), which determine the prescaler
assignment and prescale ratio.
Clearing the PSA bit assigns the prescaler to the
Timer0 module. When it is assigned, prescale values
from 1:2 through 1:256 in power-of-two increments are
selectable.
When assigned to the Timer0 module, all instructions
writing to the TMR0 register (for example, CLRF TMR0,
MOVWF TMR0, BSF TMR0) clear the prescaler count.
13.3.1 SWITCHING PRESCALER
ASSIGNMENT
The prescaler assignment is fully under software
control and can be changed “on-the-fly” during program
execution.
13.4 Timer0 Interrupt
The TMR0 interrupt is generated when the TMR0
register overflows from FFh to 00h in 8-bit mode, or
from FFFFh to 0000h in 16-bit mode. This overflow sets
the TMR0IF flag bit. The interrupt can be masked by
clearing the TMR0IE bit (INTCON<5>). Before re-
enabling the interrupt, the TMR0IF bit must be cleared
in software by the Interrupt Service Routine (ISR).
Since Timer0 is shutdown in Sleep mode, the TMR0
interrupt cannot awaken the processor from Sleep.
TABLE 13-1: REGISTERS ASSOCIATED WITH TIMER0
Note: Writing to TMR0 when the prescaler is
assigned to Timer0 will clear the prescaler
count but will not change the prescaler
assignment.
Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
TMR0L Timer0 Register Low Byte
TMR0H Timer0 Register High Byte
INTCON GIE/GIEH PEIE/GIEL TMR0IE INT0IE RBIE TMR0IF INT0IF RBIF
T0CON TMR0ON T08BIT T0CS T0SE PSA T0PS2 T0PS1 T0PS0
Legend: — = unimplemented, read as ‘0’. Shaded cells are not used by Timer0.
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NOTES:
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14.0 TIMER1 MODULE
The Timer1 timer/counter module incorporates these
features:
• Software-selectable operation as a 16-bit timer or
counter
• Readable and writable 8-bit registers (TMR1H
and TMR1L)
• Selectable clock source (internal or external) with
device clock or SOSC oscillator internal options
• Interrupt-on-overflow
• Reset on ECCP Special Event Trigger
• Timer with gated control
Figure 14-1 displays a simplified block diagram of the
Timer1 module.
The Timer1 oscillator can also be used as a low-power
clock source for the microcontroller in power-managed
operation. The Timer1 can also work on the SOSC
oscillator.
Timer1 is controlled through the T1CON Control
register (Register 14-1). It also contains the Secondary
Oscillator Enable bit (SOSCEN). Timer1 can be
enabled or disabled by setting or clearing control bit,
TMR1ON (T1CON<0>).
The FOSC clock source should not be used with the
ECCP capture/compare features. If the timer will be
used with the capture or compare features, always
select one of the other timer clocking options.
REGISTER 14-1: T1CON: TIMER1 CONTROL REGISTER
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0
TMR1CS1 TMR1CS0 T1CKPS1 T1CKPS0 SOSCEN T1SYNC RD16 TMR1ON
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7-6 TMR1CS<1:0>: Timer1 Clock Source Select bits
10 = Timer1 clock source is either from a pin or oscillator, depending on the SOSCEN bit:
SOSCEN = 0:
External clock from the T1CKI pin (on the rising edge).
SOSCEN = 1:
Depending on the SOSCSEL Configuration bit the clock source is either a crystal oscillator on the
SOSCI/SOSCO pins or an internal clock from the SCLKI pin.
01 = Timer1 clock source is the system clock (FOSC)(1)
00 = Timer1 clock source is the instruction clock (FOSC/4)
bit 5-4 T1CKPS<1:0>: Timer1 Input Clock Prescale Select bits
11 = 1:8 Prescale value
10 = 1:4 Prescale value
01 = 1:2 Prescale value
00 = 1:1 Prescale value
bit 3 SOSCEN: SOSC Oscillator Enable bit
1 = SOSC is enabled and available for Timer1
0 = SOSC is disabled for Timer1
The oscillator inverter and feedback resistor are turned off to eliminate power drain.
bit 2 T1SYNC: Timer1 External Clock Input Synchronization Select bit
TMR1CS<1:0> = 10:
1 = Do not synchronize external clock input
0 = Synchronize external clock input
TMR1CS<1:0> = 0x:
This bit is ignored. Timer1 uses the internal clock when TMR1CS<1:0> = 1x.
bit 1 RD16: 16-Bit Read/Write Mode Enable bit
1 = Enables register read/write of Timer1 in one 16-bit operation
0 = Enables register read/write of Timer1 in two 8-bit operations
bit 0 TMR1ON: Timer1 On bit
1 = Enables Timer1
0 =Stops Timer1
Note 1: The FOSC clock source should not be selected if the timer will be used with the ECCP capture/compare features.
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14.1 Timer1 Gate Control Register
The Timer1 Gate Control register (T1GCON),
displayed in Register 14-2, is used to control the
Timer1 gate.
REGISTER 14-2: T1GCON: TIMER1 GATE CONTROL REGISTER(1)
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R-x R/W-0 R/W-0
TMR1GE T1GPOL T1GTM T1GSPM T1GGO/T1DONE T1GVAL T1GSS1 T1GSS0
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 TMR1GE: Timer1 Gate Enable bit
If TMR1ON = 0:
This bit is ignored.
If TMR1ON = 1:
1 = Timer1 counting is controlled by the Timer1 gate function
0 = Timer1 counts regardless of Timer1 gate function
bit 6 T1GPOL: Timer1 Gate Polarity bit
1 = Timer1 gate is active-high (Timer1 counts when gate is high)
0 = Timer1 gate is active-low (Timer1 counts when gate is low)
bit 5 T1GTM: Timer1 Gate Toggle Mode bit
1 = Timer1 Gate Toggle mode is enabled
0 = Timer1 Gate Toggle mode is disabled and toggle flip-flop is cleared
Timer1 gate flip-flop toggles on every rising edge.
bit 4 T1GSPM: Timer1 Gate Single Pulse Mode bit
1 = Timer1 Gate Single Pulse mode is enabled and is controlling Timer1 gate
0 = Timer1 Gate Single Pulse mode is disabled
bit 3 T1GGO/T1DONE: Timer1 Gate Single Pulse Acquisition Status bit
1 = Timer1 gate single pulse acquisition is ready, waiting for an edge
0 = Timer1 gate single pulse acquisition has completed or has not been started
This bit is automatically cleared when T1GSPM is cleared.
bit 2 T1GVAL: Timer1 Gate Current State bit
Indicates the current state of the Timer1 gate that could be provided to TMR1H:TMR1L; unaffected by
Timer1 Gate Enable (TMR1GE) bit.
bit 1-0 T1GSS<1:0>: Timer1 Gate Source Select bits
11 = Comparator 2 output
10 = Comparator 1 output
01 = TMR2 to match PR2 output
00 = Timer1 gate pin
Note 1: Programming the T1GCON prior to T1CON is recommended.
2011 Microchip Technology Inc. DS39960C-page 199
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14.2 Timer1 Operation
The Timer1 module is an 8 or 16-bit incrementing
counter that is accessed through the TMR1H:TMR1L
register pair.
When used with an internal clock source, the module is
a timer and increments on every instruction cycle.
When used with an external clock source, the module
can be used as either a timer or counter. It increments
on every selected edge of the external source.
Timer1 is enabled by configuring the TMR1ON and
TMR1GE bits in the T1CON and T1GCON registers,
respectively.
When SOSC is selected as Crystal mode (by
SOSCSEL), the RC1/SOSCI/ECCP2/P2A and RC0/
SOSCO/SCLKI pins become inputs. This means the
values of TRISC<1:0> are ignored and the pins are
read as ‘0’.
14.3 Clock Source Selection
The TMR1CS<1:0> and SOSCEN bits of the T1CON
register are used to select the clock source for Timer1.
Register 14-1 displays the clock source selections.
14.3.1 INTERNAL CLOCK SOURCE
When the internal clock source is selected, the
TMR1H:TMR1L register pair will increment on multiples
of FOSC as determined by the Timer1 prescaler.
14.3.2 EXTERNAL CLOCK SOURCE
When the external clock source is selected, the Timer1
module may work as a timer or a counter.
When enabled to count, Timer1 is incremented on the
rising edge of the external clock input, T1CKI. Either of
these external clock sources can be synchronized to the
microcontroller system clock or they can run
asynchronously.
When used as a timer with a clock oscillator, an
external, 32.768 kHz crystal can be used in conjunction
with the dedicated internal oscillator circuit.
TABLE 14-1: TIMER1 CLOCK SOURCE SELECTION
Note: In Counter mode, a falling edge must be
registered by the counter prior to the first
incrementing rising edge after any one or
more of the following conditions:
• Timer1 enabled after POR Reset
• Write to TMR1H or TMR1L
• Timer1 is disabled
• Timer1 is disabled (TMR1ON = 0)
When T1CKI is high, Timer1 is enabled
(TMR1ON = 1) when T1CKI is low.
TMR1CS1 TMR1CS0 SOSCEN Clock Source
01xClock Source (FOSC)
00xInstruction Clock (FOSC/4)
100External Clock on T1CKI Pin
101Oscillator Circuit on SOSCI/SOSCO Pins
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DS39960C-page 200 2011 Microchip Technology Inc.
FIGURE 14-1: TIMER1 BLOCK DIAGRAM
TMR1H TMR1L
T1SYNC
T1CKPS<1:0>
Prescaler
1, 2, 4, 8
0
1
Synchronized
Clock Input
2
Set Flag bit,
TMR1IF, on
Overflow TMR1(2)
TMR1ON
Note 1: ST Buffer is high-speed type when using T1CKI.
2: Timer1 register increments on rising edge.
3: Synchronize does not operate while in Sleep.
4: The output of SOSC is determined by the SOSCSEL<1:0> Configuration bits.
T1G
SOSC
FOSC/4
Internal
Clock
SOSCO/SCLKI
SOSCI
1
0
T1CKI
TMR1CS<1:0>
(1)
Synchronize(3)
det
Sleep Input
TMR1GE
0
1
00
01
10
11
From TMR2
From Comparator 1
T1GPOL
D
Q
CK
Q
0
1
T1GVAL
T1GTM
Single Pulse
Acq. Control
T1GSPM
T1GGO/T1DONE
T1GSS<1:0>
EN
OUT(4)
10
00
01
FOSC
Internal
Clock
From Comparator 2
Match PR2
R
D
EN
Q
Q1
RD
T1GCON
Data Bus
det
Interrupt
TMR1GIF
Set
T1CLK
FOSC/2
Internal
Clock
D
EN
Q
T1G_IN
TMR1ON
Output
Output
T1CON.SOSCEN
T3CON.SOSCEN
SOSCGO
SCS<1:0> = 01
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14.4 Timer1 16-Bit Read/Write Mode
Timer1 can be configured for 16-bit reads and writes.
When the RD16 control bit (T1CON<1>) is set, the
address for TMR1H is mapped to a buffer register for
the high byte of Timer1. A read from TMR1L loads the
contents of the high byte of Timer1 into the Timer1 High
Byte Buffer register. This provides the user with the
ability to accurately read all 16 bits of Timer1 without
having to determine whether a read of the high byte,
followed by a read of the low byte, has become invalid
due to a rollover between reads.
A write to the high byte of Timer1 must also take place
through the TMR1H Buffer register. The Timer1 high
byte is updated with the contents of TMR1H when a
write occurs to TMR1L. This allows a user to write all
16 bits at once to both the high and low bytes of Timer1.
The high byte of Timer1 is not directly readable or
writable in this mode. All reads and writes must take
place through the Timer1 High Byte Buffer register.
Writes to TMR1H do not clear the Timer1 prescaler.
The prescaler is only cleared on writes to TMR1L.
14.5 SOSC Oscillator
An on-chip crystal oscillator circuit is incorporated
between pins, SOSCI (input) and SOSCO (amplifier
output). It is enabled by any peripheral that requests it.
There are eight ways the SOSC can be enabled: if the
SOSC is selected as the source by any of the odd
timers, which is done by each respective SOSCEN bit
(TxCON<3>), if the SOSC is selected as the RTCC
source by the RTCOSC Configuration bit
(CONFIG3L<1>), if the SOSC is selected as the CPU
clock source by the SCS bits (OSCCON<1:0>) or if the
SOSCGO bit is set (OSCCON2<3>). The SOSCGO bit
is used to warm up the SOSC so that it is ready before
any peripheral requests it. The oscillator is a low-power
circuit, rated for 32 kHz crystals. It will continue to run
during all power-managed modes. The circuit for a typi-
cal low-power oscillator is depicted in Figure 14-2.
Table 14-2 provides the capacitor selection for the
SOSC oscillator.
The user must provide a software time delay to ensure
proper start-up of the SOSC oscillator.
FIGURE 14-2:
EXTERNAL COMPONENT S
FOR THE SOS C
LOW-POW ER
OSCILLATOR
T ABLE 14-2: CAPACITOR SELECTION FOR
THE TIMER
OSCILLATOR(2,3,4,5)
The SOSC crystal oscillator drive level is determined
based on the SOSCSEL (CONFIG1L<4:3>) Con-
figuration bits. The Higher Drive Level mode,
SOSCSEL<1:0> = 11, is intended to drive a wide variety
of 32.768 kHz crystals with a variety of Capacitance
Load (CL) ratings.
Oscillator
Type Freq. C1 C2
LP 32 kHz 12 pF(1) 12 pF(1)
Note 1: Microchip suggests these values as a
starting point in validating the oscillator
circuit.
2: Higher capacitance increases the stabil-
ity of the oscillator, but also increases the
start-up time.
3: Since each resonator/crystal has its own
characteristics, the user should consult
the resonator/crystal manufacturer for
appropriate values of external
components.
4: Capacitor values are for design guid-
ance only. Values listed would be typical
of a CL = 10 pF rated crystal, when
SOSCSEL = 11.
5: Incorrect capacitance value may result in
a frequency not meeting the crystal
manufacturer’s tolerance specification.
Note: See the Notes with Table 14-2 for additional
information about capacitor selection.
C1
C2
XTAL
SOSCI
SOSCO
32.768 kHz
12 pF
12 pF
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The Lower Drive Level mode is highly optimized for
extremely low-power consumption. It is not intended to
drive all types of 32.768 kHz crystals. In the Low Drive
Level mode, the crystal oscillator circuit may not work
correctly if excessively large discrete capacitors are
placed on the SOSCO and SOSCI pins. This mode is
designed to work only with discrete capacitances of
approximately 3 pF-10 pF on each pin.
Crystal manufacturers usually specify a CL (Load
Capacitance) rating for their crystals. This value is
related to, but not necessarily the same as, the values
that should be used for C1 and C2 in Figure 14-2.
For more details on selecting the optimum C1 and C2
for a given crystal, see the crystal manufacturer’s appli-
cations information. The optimum value depends in
part on the amount of parasitic capacitance in the
circuit, which is often unknown. For that reason, it is
highly recommended that thorough testing and valida-
tion of the oscillator be performed after values have
been selected.
14.5.1 USING SOSC AS A
CLOCK SOURCE
The SOSC oscillator is also available as a clock source
in power-managed modes. By setting the clock select
bits, SCS<1:0> (OSCCON<1:0>), to ‘01’, the device
switches to SEC_RUN mode and both the CPU and
peripherals are clocked from the SOSC oscillator. If the
IDLEN bit (OSCCON<7>) is cleared and a SLEEP
instruction is executed, the device enters SEC_IDLE
mode. Additional details are available in Section 4.0
“Power-M ana ged Modes”.
Whenever the SOSC oscillator is providing the clock
source, the SOSC System Clock Status flag,
SOSCRUN (OSCCON2<6>), is set. This can be used
to determine the controller’s current clocking mode. It
can also indicate the clock source currently being used
by the Fail-Safe Clock Monitor.
If the Clock Monitor is enabled and the SOSC oscillator
fails while providing the clock, polling the SOCSRUN
bit will indicate whether the clock is being provided by
the SOSC oscillator or another source.
14.5.2 SOSC OSCILLATOR LAYOUT
CONSIDERATIONS
The SOSC oscillator circuit draws very little power
during operation. Due to the low-power nature of the
oscillator, it may also be sensitive to rapidly changing
signals in close proximity. This is especially true when
the oscillator is configured for extremely low-power
mode, SOSCSEL<1:0> (CONFIG1L<4:3>) = 01.
The oscillator circuit, displayed in Figure 14-2, should
be located as close as possible to the microcontroller.
There should be no circuits passing within the oscillator
circuit boundaries other than VSS or VDD.
If a high-speed circuit must be located near the
oscillator, it may help to have a grounded guard ring
around the oscillator circuit. The guard, as displayed in
Figure 14-3, could be used on a single-sided PCB or in
addition to a ground plane. (Examples of a high-speed
circuit include the ECCP1 pin, in Output Compare or
PWM mode, or the primary oscillator, using the
OSC2 pin.)
FIGURE 14-3: OSCILLATOR CIRCUIT
WITH GROUNDED
GUARD RING
In the Low Drive Level mode, SOSCSEL<1:0> = 01, it is
critical that RC2 I/O pin signals be kept away from the
oscillator circuit. Configuring RC2 as a digital output, and
toggling it, can potentially disturb the oscillator circuit,
even with a relatively good PCB layout. If possible, either
leave RC2 unused or use it as an input pin with a slew
rate limited signal source. If RC2 must be used as a
digital output, it may be necessary to use the Higher
Drive Level Oscillator mode (SOSCSEL<1:0> = 11) with
many PCB layouts.
Even in the Higher Drive Level mode, careful layout
procedures should still be followed when designing the
oscillator circuit.
In addition to dV/dt induced noise considerations, it is
important to ensure that the circuit board is clean. Even
a very small amount of conductive soldering flux
residue can cause PCB leakage currents that can
overwhelm the oscillator circuit.
14.6 Timer1 Interrupt
The TMR1 register pair (TMR1H:TMR1L) increments
from 0000h to FFFFh and rolls over to 0000h. The
Timer1 interrupt, if enabled, is generated on overflow
which is latched in interrupt flag bit, TMR1IF
(PIR1<0>). This interrupt can be enabled or disabled
by setting or clearing the Timer1 Interrupt Enable bit,
TMR1IE (PIE1<0>).
VDD
OSC1
VSS
OSC2
RC0
RC1
RC2
Note: Not drawn to scale.
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14.7 Resetting Ti mer1 Using the ECCP
S pecial Event Trigger
If ECCP modules are configured to use Timer1 and to
generate a Special Event Trigger in Compare mode
(CCPxM<3:0> = 1011), this signal will reset Timer1. The
trigger from ECCP2 will also start an A/D conversion, if
the A/D module is enabled. (For more information, see
Section 20.3.4 “Special Event Trigger”.)
To take advantage of this feature, the module must be
configured as either a timer or a synchronous counter.
When used this way, the CCPRxH:CCPRxL register
pair effectively becomes a period register for Timer1.
If Timer1 is running in Asynchronous Counter mode,
this Reset operation may not work.
In the event that a write to Timer1 coincides with a
Special Event Trigger, the write operation will take
precedence.
14.8 Timer1 Gate
Timer1 can be configured to count freely or the count can
be enabled and disabled using the Timer1 gate circuitry.
This is also referred to as Timer1 gate count enable.
Timer1 gate can also be driven by multiple selectable
sources.
14.8.1 TIMER1 GATE COUNT ENABLE
The Timer1 Gate Enable mode is enabled by setting
the TMR1GE bit of the T1GCON register. The polarity
of the Timer1 Gate Enable mode is configured using
the T1GPOL bit (T1GCON<6>).
When Timer1 Gate Enable mode is enabled, Timer1
will increment on the rising edge of the Timer1 clock
source. When Timer1 Gate Enable mode is disabled,
no incrementing will occur and Timer1 will hold the
current count. See Figure 14-4 for timing details.
TABLE 14-3: TIMER1 GATE ENABLE
SELECTIONS
Note: The Special Event Trigger from the
ECCPx module will only clear the TMR1
register’s content, but not set the TMR1IF
interrupt flag bit (PIR1<0>).
T1CLK(†) T1GPOL
(T1GCON<6>) T1G Pin Timer1
Operation
00Counts
01Holds Count
10Holds Count
11Counts
† The clock on which TMR1 is running. For more
information, see Figure 14-1.
Note: The CCP and ECCP modules use Timers,
1 through 8, for some modes. The assign-
ment of a particular timer to a CCP/ECCP
module is determined by the Timer to CCP
enable bits in the CCPTMRSx registers.
For more details, see Register 20-2,
Register 19-2 and Register 19-3.
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FIGURE 14-4: TIMER1 GATE COUNT ENABLE MODE
14.8.2 TIMER1 GATE SOURCE
SELECTION
The Timer1 gate source can be selected from one of
four sources. Source selection is controlled by the
T1GSSx (T1GCON<1:0>) bits (see Table 14-4).
TABLE 14-4: TIMER1 GATE SOURCES
The polarity for each available source is also selectable,
controlled by the T1GPOL bit (T1GCON<6>).
14.8.2.1 T1G Pin Gate Operation
The T1G pin is one source for Timer1 gate control. It
can be used to supply an external source to the Timer1
gate circuitry.
14.8.2.2 Timer2 Match Gate Operation
The TMR2 register will increment until it matches the
value in the PR2 register. On the very next increment
cycle, TMR2 will be reset to 00h. When this Reset
occurs, a low-to-high pulse will automatically be gener-
ated and internally supplied to the Timer1 gate circuitry.
The pulse will remain high for one instruction cycle and
will return back to a low state until the next match.
The T1GPOL bit determines when the Timer1 counter
increments based on this pulse. When T1GPOL = 1,
Timer1 increments for a single instruction cycle follow-
ing a TMR2 match with PR2. When T1GPOL = 0,
Timer1 increments continuously, except for the cycle
following the match, when the gate signal goes from
low-to-high.
14.8.2.3 Comparator 1 Output Gate
Operation
The output of Comparator 1 can be internally supplied
to the Timer1 gate circuitry. After setting up
Comparator 1 with the CM1CON register, Timer1 will
increment depending on the transitions of the
CMP1OUT (CMSTAT<5>) bit.
14.8.2.4 Comparator 2 Output Gate
Operation
The output of Comparator 2 can be internally supplied
to the Timer1 gate circuitry. After setting up
Comparator 2 with the CM2CON register, Timer1 will
increment depending on the transitions of the
CMP2OUT (CMSTAT<6>) bit.
TMR1GE
T1GPOL
T1G_IN
T1CKI
T1GVAL
Timer1 N N + 1 N + 2 N + 3 N + 4
T1GSS<1:0> Timer1 Gate Source
00 Timer1 Gate Pin
01 TMR2 to Match PR2
(TMR2 increments to match PR2)
10 Comparator 1 Output
(comparator logic high output)
11 Comparator 2 Output
(comparator logic high output)
2011 Microchip Technology Inc. DS39960C-page 205
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14.8.3 TIMER1 GATE TOGGLE MODE
When Timer1 Gate Toggle mode is enabled, it is
possible to measure the full cycle length of a Timer1
gate signal, as opposed to the duration of a single level
pulse.
The Timer1 gate source is routed through a flip-flop that
changes state on every incrementing edge of the
signal. (For timing details, see Figure 14-5.)
The T1GVAL bit (T1GCON<2>) indicates when the
Toggled mode is active and the timer is counting.
The Timer1 Gate Toggle mode is enabled by setting the
T1GTM bit (T1GCON<5>). When T1GTM is cleared,
the flip-flop is cleared and held clear. This is necessary
in order to control which edge is measured.
FIGURE 14-5: TIMER1 GATE TOGGLE MODE
TMR1GE
T1GPOL
T1GTM
T1G_IN
T1CKI
T1GVAL
Timer1 N N + 1 N + 2 N + 3 N + 4 N + 5 N + 6 N + 7 N + 8
PIC18F87K22 FAMILY
DS39960C-page 206 2011 Microchip Technology Inc.
14.8.4 TIMER1 GATE SINGLE PULSE
MODE
When Timer1 Gate Single Pulse mode is enabled, it is
possible to capture a single pulse gate event. Timer1
Gate Single Pulse mode is enabled by setting the
T1GSPM bit (T1GCON<4>) and the T1GGO/T1DONE
bit (T1GCON<3>). The Timer1 will be fully enabled on
the next incrementing edge.
On the next trailing edge of the pulse, the T1GGO/
T1DONE bit will automatically be cleared. No other
gate events will be allowed to increment Timer1 until
the T1GGO/T1DONE bit is once again set in software.
Clearing the T1GSPM bit of the T1GCON register will
also clear the T1GGO/T1DONE bit. (For timing details,
see Figure 14-6.)
Simultaneously enabling the Toggle and Single Pulse
modes will permit both sections to work together. This
allows the cycle times on the Timer1 gate source to be
measured. (For timing details, see Figure 14-7.)
14.8.5 TIMER1 GATE VALUE STATUS
When the Timer1 gate value status is utilized, it is
possible to read the most current level of the gate
control value. The value is stored in the T1GVAL bit
(T1GCON<2>). This bit is valid even when the Timer1
gate is not enabled (TMR1GE bit is cleared).
FIGURE 14-6: TIMER1 GATE SINGLE PULSE MODE
TMR1GE
T1GPOL
T1G_IN
T1CKI
T1GVAL
Timer1 N N + 1 N + 2
T1GSPM
T1GGO/
T1DONE
Set by Software
Cleared by Hardware on
Falling Edge of T1GVAL
Set by Hardware on
Falling Edge of T1GVAL
Cleared by Software
Cleared by
Software
RTCCIF
Counting Enabled on
Rising Edge of T1G
2011 Microchip Technology Inc. DS39960C-page 207
PIC18F87K22 FAMILY
FIGURE 14-7: TIMER1 GATE SINGLE PULSE AND TOGGLE COMBINED MODE
TABLE 14-5: REGISTERS ASSOCIATED WITH TIMER1 AS A TIMER/COUNTER
Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
INTCON GIE/GIEH PEIE/GIEL TMR0IE INT0IE RBIE TMR0IF INT0IF RBIF
PIR1 PSPIF ADIF RC1IF TX1IF SSP1IF TMR1GIF TMR2IF TMR1IF
PIE1 PSPIE ADIE RC1IE TX1IE SSP1IE TMR1GIE TMR2IE TMR1IE
IPR1 PSPIP ADIP RC1IP TX1IP SSP1IP TMR1GIP TMR2IP TMR1IP
TMR1L Timer1 Register Low Byte
TMR1H Timer1 Register High Byte
T1CON TMR1CS1 TMR1CS0 T1CKPS1 T1CKPS0 SOSCEN T1SYNC RD16 TMR1ON
T1GCON TMR1GE T1GPOL T1GTM T1GSPM T1GGO/
T1DONE
T1GVAL T1GSS1 T1GSS0
OSCCON2 — SOSCRUN ——SOSCGO— MFIOFS MFIOSEL
PMD1 PSPMD CTMUMD RTCCMD TMR4MD TMR3MD TMR2MD TMR1MD EMBDM
Legend: Shaded cells are not used by the Timer1 module.
Note 1: Unimplemented on 32-Kbyte devices (PIC18FX5K22).
TMR1GE
T1GPOL
T1G_IN
T1CKI
T1GVAL
Timer1 NN + 1 N + 2
T1GSPM
T1GGO/
T1DONE
Set by Software
Cleared by Hardware on
Falling Edge of T1GVAL
Set by Hardware on
Falling Edge of T1GVAL
Cleared by Software
Cleared by
Software
RTCCIF
T1GTM
Counting Enabled on
Rising Edge of T1G
N + 4
N + 3
PIC18F87K22 FAMILY
DS39960C-page 208 2011 Microchip Technology Inc.
NOTES:
2011 Microchip Technology Inc. DS39960C-page 209
PIC18F87K22 FAMILY
15.0 TIMER2 MODULE
The Timer2 module incorporates the following features:
• Eight-bit Timer and Period registers (TMR2 and
PR2, respectively)
• Both registers readable and writable
• Software programmable prescaler
(1:1, 1:4 and 1:16)
• Software programmable postscaler
(1:1 through 1:16)
• Interrupt on TMR2 to PR2 match
• Optional use as the shift clock for the
MSSP modules
The module is controlled through the T2CON register
(Register 15-1) that enables or disables the timer, and
configures the prescaler and postscaler. Timer2 can be
shut off by clearing control bit, TMR2ON (T2CON<2>),
to minimize power consumption.
A simplified block diagram of the module is shown in
Figure 15-1.
15.1 Timer2 Operation
In normal operation, TMR2 is incremented from 00h on
each clock (FOSC/4). A four-bit counter/prescaler on the
clock input gives the prescale options of direct input,
divide-by-4 or divide-by-16. These are selected by the
prescaler control bits, T2CKPS<1:0> (T2CON<1:0>).
The value of TMR2 is compared to that of the Period reg-
ister, PR2, on each clock cycle. When the two values
match, the comparator generates a match signal as the
timer output. This signal also resets the value of TMR2
to 00h on the next cycle and drives the output counter/
postscaler. (See Section 15.2 “Timer2 Interrupt”.)
The TMR2 and PR2 registers are both directly readable
and writable. The TMR2 register is cleared on any
device Reset, while the PR2 register initializes at FFh.
Both the prescaler and postscaler counters are cleared
on the following events:
• A write to the TMR2 register
• A write to the T2CON register
• Any device Reset – Power-on Reset (POR),
MCLR Reset, Watchdog Timer Reset (WDTR) or
Brown-out Reset (BOR)
TMR2 is not cleared when T2CON is written.
Note: The CCP and ECCP modules use Timers,
1 through 8, for some modes. The assign-
ment of a particular timer to a CCP/ECCP
module is determined by the Timer to CCP
enable bits in the CCPTMRSx registers.
For more details, see Register 20-2,
Register 19-2 and Register 19-3.
REGISTER 15-1: T2CON: TIMER2 CONTROL REGISTER
U-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0
— T2OUTPS3 T2OUTPS2 T2OUTPS1 T2OUTPS0 TMR2ON T2CKPS1 T2CKPS0
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 Unimplemented: Read as ‘0’
bit 6-3 T2OUTPS<3:0>: Timer2 Output Postscale Select bits
0000 = 1:1 Postscale
0001 = 1:2 Postscale
•
•
•
1111 = 1:16 Postscale
bit 2 TMR2ON: Timer2 On bit
1 = Timer2 is on
0 = Timer2 is off
bit 1-0 T2CKPS<1:0>: Timer2 Clock Prescale Select bits
00 = Prescaler is 1
01 = Prescaler is 4
1x = Prescaler is 16
PIC18F87K22 FAMILY
DS39960C-page 210 2011 Microchip Technology Inc.
15.2 Timer2 Interrupt
Timer2 can also generate an optional device interrupt.
The Timer2 output signal (TMR2 to PR2 match) provides
the input for the 4-bit output counter/postscaler. This
counter generates the TMR2 match interrupt flag, which
is latched in TMR2IF (PIR1<1>). The interrupt is enabled
by setting the TMR2 Match Interrupt Enable bit, TMR2IE
(PIE1<1>).
A range of 16 postscaler options (from 1:1 through 1:16
inclusive) can be selected with the postscaler control
bits, T2OUTPS<3:0> (T2CON<6:3>).
15.3 Timer2 Output
The unscaled output of TMR2 is available primarily to
the ECCP modules, where it is used as a time base for
operations in PWM mode.
Timer2 can optionally be used as the shift clock source
for the MSSP modules operating in SPI mode.
Additional information is provided in Section 21.0
“Master Synchronous Serial Port (MSSP) Module”.
FIGURE 15-1: TIMER2 BLOCK DIAGRAM
TABLE 15-1: REGISTERS ASSOCIATED WITH TIMER2 AS A TIMER/COUNTER
Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
INTCON GIE/GIEH PEIE/GIEL TMR0IE INT0IE RBIE TMR0IF INT0IF RBIF
PIR1 PSPIF ADIF RC1IF TX1IF SSP1IF TMR1GIF TMR2IF TMR1IF
PIE1 PSPIE ADIE RC1IE TX1IE SSP1IE TMR1GIE TMR2IE TMR1IE
IPR1 PSPIP ADIP RC1IP TX1IP SSP1IP TMR1GIP TMR2IP TMR1IP
TMR2 Timer2 Register
T2CON — T2OUTPS3 T2OUTPS2 T2OUTPS1 T2OUTPS0 TMR2ON T2CKPS1 T2CKPS0
PR2 Timer2 Period Register
PMD1 PSPMD CTMUMD RTCCMD TMR4MD TMR3MD TMR2MD TMR1MD EMBDM
Legend: — = unimplemented, read as ‘0’. Shaded cells are not used by the Timer2 module.
Comparator
TMR2 Output
TMR2
Postscaler
Prescaler PR2
2
FOSC/4
1:1 to 1:16
1:1, 1:4, 1:16
4
T2OUTPS<3:0>
T2CKPS<1:0>
Set TMR2IF
Internal Data Bus
8
Reset
TMR2/PR2
8
8
(to PWM or MSSPx)
Match
2011 Microchip Technology Inc. DS39960C-page 211
PIC18F87K22 FAMILY
16.0 TIMER3/5/7 MODULES
The Timer3/5/7 timer/counter modules incorporate
these features:
• Software-selectable operation as a 16-bit timer or
counter
• Readable and writable eight-bit registers (TMRxH
and TMRxL)
• Selectable clock source (internal or external) with
device clock or SOSC oscillator internal options
• Interrupt-on-overflow
• Module Reset on ECCP Special Event Trigger
Timer7 is unimplemented for devices with program
memory of 32 Kbytes (PIC18FX5K22).
A simplified block diagram of the Timer3/5/7 module is
shown in Figure 16-1.
The Timer3/5/7 module is controlled through the
TxCON register (Register 16-1). It also selects the
clock source options for the ECCP modules. (For more
information, see Section 20.1.1 “ECCP Module and
Timer Resources”.)
The FOSC clock source should not be used with the
ECCP capture/compare features. If the timer will be
used with the capture or compare features, always
select one of the other timer clocking options.
Note: Throughout this section, generic references
are used for register and bit names that are the
same – except for an ‘x’ variable that indicates
the item’s association with the Timer3, Timer5
or Timer7 module. For example, the control
register is named TxCON and refers to
T3CON, T5CON and T7CON.
PIC18F87K22 FAMILY
DS39960C-page 212 2011 Microchip Technology Inc.
REGISTER 16-1: TxCON: TIMERx CONTROL REGISTER
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0
TMRxCS1 TMRxCS0 TxCKPS1 TxCKPS0 SOSCEN TxSYNC RD16 TMRxON
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7-6 TMRxCS<1:0>: Timerx Clock Source Select bits
10 = Timer1 clock source depends on the SOSCEN bit:
SOSCEN = 0:
External clock from the T1CKI pin (on the rising edge).
SOSCEN = 1:
Depending on the SOSCSEL fuses, either a crystal oscillator on the SOSCI/SOSCO pins or an external
clock from the SCLKI pin.
01 = Timerx clock source is the system clock (FOSC)(1)
00 = Timerx clock source is the instruction clock (FOSC/4)
bit 5-4 TxCKPS<1:0>: Timerx Input Clock Prescale Select bits
11 = 1:8 Prescale value
10 = 1:4 Prescale value
01 = 1:2 Prescale value
00 = 1:1 Prescale value
bit 3 SOSCEN: SOSC Oscillator Enable bit
1 = SOSC/SCLKI are enabled for Timerx (based on the SOSCSEL fuses)
0 = SOSC/SCLKI are disabled for Timerx and TxCKI is enabled
bit 2 TxSYNC: Timerx External Clock Input Synchronization Control bit
(Not usable if the device clock comes from Timer1/Timer3.)
When TMRxCS<1:0> = 10:
1 = Do not synchronize external clock input
0 = Synchronize external clock input
When TMRxCS<1:0> = 0x:
This bit is ignored; Timer3 uses the internal clock.
bit 1 RD16: 16-Bit Read/Write Mode Enable bit
1 = Enables register read/write of Timerx in one 16-bit operation
0 = Enables register read/write of Timerx in two eight-bit operations
bit 0 TMRxON: Timerx On bit
1 = Enables Timerx
0 = Stops Timerx
Note 1: The FOSC clock source should not be selected if the timer will be used with the ECCP capture/compare
features.
2011 Microchip Technology Inc. DS39960C-page 213
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16.1 Timer3/5/7 Gate Control Register
The Timer3/5/7 Gate Control register (TxGCON),
provided in Register 14-2, is used to control the Timerx
gate.
REGISTER 16-2: TxGCON: TIMERx GATE CONTROL REGISTER(1)
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R-x R/W-0 R/W-0
TMRxGE TxGPOL TxGTM TxGSPM TxGGO/TxDONE TxGVAL TxGSS1 TxGSS0
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 TMRxGE: Timerx Gate Enable bit
If TMRxON = 0:
This bit is ignored.
If TMRxON = 1:
1 = Timerx counting is controlled by the Timerx gate function
0 = Timerx counts regardless of Timerx gate function
bit 6 TxGPOL: Timerx Gate Polarity bit
1 = Timerx gate is active-high (Timerx counts when gate is high)
0 = Timerx gate is active-low (Timerx counts when gate is low)
bit 5 TxGTM: Timerx Gate Toggle Mode bit
1 = Timerx Gate Toggle mode is enabled.
0 = Timerx Gate Toggle mode is disabled and toggle flip-flop is cleared
Timerx gate flip-flop toggles on every rising edge.
bit 4 TxGSPM: Timerx Gate Single Pulse Mode bit
1 = Timerx Gate Single Pulse mode is enabled and is controlling Timerx gate
0 = Timerx Gate Single Pulse mode is disabled
bit 3 TxGGO/TxDONE: Timerx Gate Single Pulse Acquisition Status bit
1 = Timerx gate single pulse acquisition is ready, waiting for an edge
0 = Timerx gate single pulse acquisition has completed or has not been started
This bit is automatically cleared when TxGSPM is cleared.
bit 2 TxGVAL: Timerx Gate Current State bit
Indicates the current state of the Timerx gate that could be provided to TMRxH:TMRxL. Unaffected by the
Timerx Gate Enable (TMRxGE) bit.
bit 1-0 TxGSS<1:0>: Timerx Gate Source Select bits
11 = Comparator 2 output
10 = Comparator 1 output
01 = TMR(x+1) to match PR(x+1) output(2)
00 = Timer1 gate pin
The Watchdog Timer oscillator is turned on if TMRxGE = 1, regardless of the state of TMRxON.
Note 1: Programming the TxGCON prior to TxCON is recommended.
2: Timer(x+1) will be Timer4/6/8 for Timerx (Timer3/5/7), respectively.
PIC18F87K22 FAMILY
DS39960C-page 214 2011 Microchip Technology Inc.
REGISTER 16-3: OSCCON2: OSCILLATOR CONTROL REGISTER 2
U-0 R-0 U-0 U-0 R/W-0 U-0 R-x R/W-0
— SOSCRUN ——SOSCGO— MFIOFS MFIOSEL
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 Unimplemented: Read as ‘0’
bit 6 SOSCRUN: SOSC Run Status bit
1 = System clock comes from a secondary SOSC
0 = System clock comes from an oscillator other than SOSC
bit 5-4 Unimplemented: Read as ‘0’
bit 3 SOSCGO: Oscillator Start Control bit
1 = Oscillator is running, even if no other sources are requesting it
0 = Oscillator is shut off, if no other sources are requesting it (When the SOSC is selected to run from
a digital clock input, rather than an external crystal, this bit has no effect.)
bit 2 Unimplemented: Read as ‘0’
bit 1 MFIOFS: MF-INTOSC Frequency Stable bit
1 = MF-INTOSC is stable
0 = MF-INTOSC is not stable
bit 0 MFIOSEL: MF-INTOSC Select bit
1 = MF-INTOSC is used in place of HF-INTOSC frequencies of 500 kHz, 250 kHz and 31.25 kHz
0 = MF-INTOSC is not used
2011 Microchip Technology Inc. DS39960C-page 215
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16.2 Timer3/5/7 Operation
Timer3, Timer5 and Timer7 can operate in these
modes:
•Timer
• Synchronous Counter
• Asynchronous Counter
• Timer with Gated Control
The operating mode is determined by the clock select
bits, TMRxCSx (TxCON<7:6>). When the TMRxCSx bits
are cleared (= 00), Timer3/5/7 increments on every inter-
nal instruction cycle (FOSC/4). When TMRxCSx = 01, the
Timer3/5/7 clock source is the system clock (FOSC), and
when it is ‘10’, Timer3/5/7 works as a counter from the
external clock from the TxCKI pin (on the rising edge after
the first falling edge) or the SOSC oscillator.
FIGURE 16-1: TIME R3/5 /7 BLOCK DIAGRAM
TMR3H TMR3L
T3SYNC
T3CKPS<1:0>
Prescaler
1, 2, 4, 8
0
1
Synchronized
Clock Input
2
Set flag bit
TMR3IF on
Overflow TMR3(2)
TMR3ON
Note 1: ST Buffer is high-speed type when using T3CKI.
2: Timer3 registers increment on rising edge.
3: Synchronization does not operate while in Sleep.
4: The output of SOSC is determined by the SOSCSEL<1:0> Configuration bits.
T3G
SOSC
FOSC/4
Internal
Clock
SOSCO/SCLKI
SOSCI
1
0
T3CKI
TMR3CS<1:0>
(1)
Synchronize(3)
det
Sleep Input
TMR3GE
0
1
00
01
10
11
From TMR4
From Comparator 1
T3GPOL
D
Q
CK
Q
0
1
T3GVAL
T3GTM
Single Pulse
Acq. Control
T3GSPM
T3GGO/T3DONE
T3GSS<1:0>
EN
OUT(4)
10
00
01
FOSC
Internal
Clock
From Comparator 2
Output
Match PR4
R
D
EN
Q
Q1
RD
T3GCON
Data Bus
det
Interrupt
TMR3GIF
Set
T3CLK
FOSC/2
Internal
Clock
D
EN
Q
T3G_IN
TMR3ON
Output
T1CON.SOSCEN
T3CON.SOSCEN
SOSCGO
SCS<1:0> = 01
PIC18F87K22 FAMILY
DS39960C-page 216 2011 Microchip Technology Inc.
16.3 Timer3/5/7 16-Bit Read/Write Mode
Timer3/5/7 can be configured for 16-bit reads and
writes (see Figure 16.3). When the RD16 control bit
(TxCON<1>) is set, the address for TMRxH is mapped
to a buffer register for the high byte of Timer3/5/7. A
read from TMRxL will load the contents of the high byte
of Timer3/5/7 into the Timerx High Byte Buffer register.
This provides users with the ability to accurately read
all 16 bits of Timer3/5/7 without having to determine
whether a read of the high byte, followed by a read of
the low byte, has become invalid due to a rollover
between reads.
A write to the high byte of Timer3/5/7 must also take
place through the TMRxH Buffer register. The Timer3/
5/7 high byte is updated with the contents of TMRxH
when a write occurs to TMRxL. This allows users to
write all 16 bits to both the high and low bytes of
Timer3/5/7 at once.
The high byte of Timer3/5/7 is not directly readable or
writable in this mode. All reads and writes must take
place through the Timerx High Byte Buffer register.
Writes to TMRxH do not clear the Timer3/5/7 prescaler.
The prescaler is only cleared on writes to TMRxL.
16.4 Using the SOSC Oscillator as the
Timer3/5/7 Clock Source
The SOSC internal oscillator may be used as the clock
source for Timer3/5/7. The SOSC oscillator is enabled
by any peripheral that requests it. There are eight ways
the SOSC can be enabled: if the SOSC is selected as
the source by any of the odd timers, which is done by
each respective SOSCEN bit (TxCON<3>), if the
SOSC is selected as the RTCC source by the RTCOSC
Configuration bit (CONFIG3L<1>), if the SOSC is
selected as the CPU clock source by the SCS bits
(OSCCON<1:0>) or if the SOSCGO bit is set
(OSCCON2<3>). The SOSCGO bit is used to warm up
the SOSC so that it is ready before any peripheral
requests it. To use it as the Timer3/5/7 clock source, the
TMRxCS bit must also be set. As previously noted, this
also configures Timer3/5/7 to increment on every rising
edge of the oscillator source.
The SOSC oscillator is described in Section 14.5
“SOSC Oscil l at or ”.
2011 Microchip Technology Inc. DS39960C-page 217
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16.5 Timer3/5/7 Gates
Timer3/5/7 can be configured to count freely or the count
can be enabled and disabled using the Timer3/5/7 gate
circuitry. This is also referred to as the Timer3/5/7 gate
count enable.
The Timer3/5/7 gate can also be driven by multiple
selectable sources.
16.5.1 TIMER3/5/7 GATE COUNT ENABLE
The Timerx Gate Enable mode is enabled by setting
the TMRxGE bit (TxGCON<7>). The polarity of the
Timerx Gate Enable mode is configured using the
TxGPOL bit (TxGCON<6>).
When Timerx Gate Enable mode is enabled, Timer3/5/7
will increment on the rising edge of the Timer3/5/7 clock
source. When Timerx Gate Enable mode is disabled, no
incrementing will occur and Timer3/5/7 will hold the
current count. See Figure 16-2 for timing details.
TABLE 16-1: TIMER3/5/7 GATE ENABLE
SELECTIONS
FIGURE 16-2: TIMER3/5/7 GATE COUNT ENABLE MODE
TxCLK(†) TxGPOL
(TxGCON<6>) TxG Pin Timerx
Operation
00Counts
01Holds Count
10Holds Count
11Counts
† The clock on which TMR3/5/7 is running. For
more information, see TxCLK in Figure 16-1.
TMRxGE
TxGPOL
TxG_IN
TxCKI
TxGVAL
Timer3/5/7 N N + 1 N + 2 N + 3 N + 4
PIC18F87K22 FAMILY
DS39960C-page 218 2011 Microchip Technology Inc.
16.5.2 TIMER3/5/7 GATE SOURCE
SELECTION
The Timer3/5/7 gate source can be selected from one
of four different sources. Source selection is controlled
by the TxGSS<1:0> bits (TxGCON<1:0>). The polarity
for each available source is also selectable and is
controlled by the TxGPOL bit (TxGCON <6>).
TABLE 16-2: TIMER3/5/7 GATE SOURCES
16.5.2.1 TxG Pin Gate Operation
The TxG pin is one source for Timer3/5/7 gate control. It
can be used to supply an external source to the Timerx
gate circuitry.
16.5.2.2 Timer4/6/8 Match Gate Operation
The TMR(x+1) register will increment until it matches the
value in the PR(x+1) register. On the very next increment
cycle, TMR2 will be reset to 00h. When this Reset
occurs, a low-to-high pulse will automatically be gener-
ated and internally supplied to the Timerx gate circuitry.
The pulse will remain high for one instruction cycle and
will return back to a low state until the next match.
Depending on TxGPOL, Timerx increments differently
when TMR(x+1) matches PR(x+1). When
TxGPOL = 1, Timerx increments for a single instruction
cycle following a TMR(x+1) match with PR(x+1). When
TxGPOL = 0, Timerx increments continuously, except
for the cycle following the match, when the gate signal
goes from low-to-high.
16.5.2.3 Comparator 1 Output Gate
Operation
The output of Comparator1 can be internally supplied
to the Timerx gate circuitry. After setting up
Comparator 1 with the CM1CON register, Timerx will
increment depending on the transitions of the
CMP1OUT (CMSTAT<5>) bit.
16.5.2.4 Comparator 2 Output Gate
Operation
The output of Comparator 2 can be internally supplied
to the Timerx gate circuitry. After setting up
Comparator 2 with the CM2CON register, Timerx will
increment depending on the transitions of the
CMP2OUT (CMSTAT<6>) bit.
16.5.3 TIMER3/5/7 GATE TOGGLE MODE
When Timer3/5/7 Gate Toggle mode is enabled, it is
possible to measure the full cycle length of a Timer3/5/7
gate signal, as opposed to the duration of a single level
pulse.
The Timerx gate source is routed through a flip-flop that
changes state on every incrementing edge of the
signal. (For timing details, see Figure 16-3.)
The TxGVAL bit will indicate when the Toggled mode is
active and the timer is counting.
Timer3/5/7 Gate Toggle mode is enabled by setting the
TxGTM bit (TxGCON<5>). When the TxGTM bit is
cleared, the flip-flop is cleared and held clear. This is
necessary in order to control which edge is measured.
FIGURE 16-3: TIMER3/5/7 GATE TOGGLE MODE
TxGSS<1:0> T ime rx Gate Source
00 Timerx Gate Pin
01 TMR(x+1) to Match PR(x+1)
(TMR(x+1) increments to match
PR(x+1))
10 Comparator 1 Output
(comparator logic high output)
11 Comparator 2 Output
(comparator logic high output)
TMRxGE
TxGPOL
TxGTM
TxG_IN
TxCKI
TxGVAL
Timer3/5/7 N N + 1 N + 2 N + 3 N + 4 N + 5 N + 6 N + 7 N + 8
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16.5.4 TIMER3/5/7 GATE SINGLE PULSE
MODE
When Timer3/5/7 Gate Single Pulse mode is enabled,
it is possible to capture a single pulse gate event.
Timer3/5/7 Gate Single Pulse mode is first enabled by
setting the TxGSPM bit (TxGCON<4>). Next, the
TxGGO/TxDONE bit (TxGCON<3>) must be set.
The Timer3/5/7 will be fully enabled on the next incre-
menting edge. On the next trailing edge of the pulse,
the TxGGO/TxDONE bit will automatically be cleared.
No other gate events will be allowed to increment
Timer3/5/7 until the TxGGO/TxDONE bit is once again
set in software.
Clearing the TxGSPM bit also will clear the TxGGO/
TxDONE bit. (For timing details, see Figure 16-4.)
Simultaneously enabling the Toggle mode and the
Single Pulse mode will permit both sections to work
together. This allows the cycle times on the Timer3/5/7
gate source to be measured. (For timing details, see
Figure 16-5.)
FIGURE 16-4: TIMER3/5/7 GATE SINGLE PULSE MODE
TMRxGE
TxGPOL
TxG_IN
TxCKI
TxGVAL
Timer3/5/7 N N + 1 N + 2
TxGSPM
TxGGO/
TxDONE
Set by Software
Cleared by Hardware on
Falling Edge of TxGVAL
Set by Hardware on
Falling Edge of TxGVAL
Cleared by Software
Cleared by
Software
TMRxGIF
Counting Enabled on
Rising Edge of TxG
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DS39960C-page 220 2011 Microchip Technology Inc.
FIGURE 16-5: TIMER3/5/7 GATE SINGLE PULSE AND TOGGLE COMBINED MODE
16.5.5 TIMER3/5/7 GATE VALUE STATUS
When Timer3/5/7 gate value status is utilized, it is
possible to read the most current level of the gate con-
trol value. The value is stored in the TxGVAL bit
(TxGCON<2>). The TxGVAL bit is valid even when the
Timer3/5/7 gate is not enabled (TMRxGE bit is
cleared).
16.5.6 TIMER3/5/7 GATE EVENT
INTERRUPT
When the Timer3/5/7 gate event interrupt is enabled, it
is possible to generate an interrupt upon the comple-
tion of a gate event. When the falling edge of TxGVAL
occurs, the TMRxGIF flag bit in the PIRx register will be
set. If the TMRxGIE bit in the PIEx register is set, then
an interrupt will be recognized.
The TMRxGIF flag bit operates even when the
Timer3/5/7 gate is not enabled (TMRxGE bit is
cleared).
TMRxGE
TxGPOL
TxG_IN
TxCKI
TxGVAL
Timer3/5/7 N N + 1 N + 2
TxGSPM
TxGGO/
TxDONE
Set by Software
Cleared by Hardware on
Falling Edge of TxGVAL
Set by Hardware on
Falling Edge of TxGVAL
Cleared by Software
Cleared by
Software
TMRxGIF
TxGTM
Counting Enabled on
Rising Edge of TxG
N + 4N + 3
2011 Microchip Technology Inc. DS39960C-page 221
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16.6 Timer3/5/7 Interrupt
The TMRx register pair (TMRxH:TMRxL) increments
from 0000h to FFFFh and overflows to 0000h. The
Timerx interrupt, if enabled, is generated on overflow
and is latched in the interrupt flag bit, TMRxIF.
Table 16-3 gives each module’s flag bit.
This interrupt can be enabled or disabled by setting or
clearing the TMRxIE bit, respectively. Table 16-4 gives
each module’s enable bit.
16.7 Resetting Timer3/5/7 Using the
ECCP Special Event Trigger
If the ECCP modules are configured to use Timerx and
to generate a Special Event Trigger in Compare mode
(CCPxM<3:0> = 1011), this signal will reset Timerx. The
trigger from ECCP2 will also start an A/D conversion if
the A/D module is enabled (For more information, see
Section 20.3.4 “Special Event Trigger”.)
The module must be configured as either a timer or
synchronous counter to take advantage of this feature.
When used this way, the CCPRxH:CCPRxL register
pair effectively becomes a Period register for Timerx.
If Timerx is running in Asynchronous Counter mode,
the Reset operation may not work.
In the event that a write to Timerx coincides with a
Special Event Trigger from an ECCP module, the write
will take precedence.
TABLE 16-3: TIMER3/5/7 INTERRUPT
FLAG BITS
Time r Module Fla g Bit
3 PIR2<1>
5 PIR5<1>
7 PIR5<3>
TABLE 16-4: TIMER3/5/7 INTERRUPT
ENABLE BITS
Time r Module Fla g Bit
3 PIE2<1>
5 PIE5<1>
7 PIE5<3>
Note: The Special Event Triggers from the
ECCPx module will only clear the TMR3
register’s content, but not set the TMR3IF
interrupt flag bit (PIR1<0>).
Note: The CCP and ECCP modules use Timers,
1 through 8, for some modes. The assign-
ment of a particular timer to a CCP/ECCP
module is determined by the Timer to CCP
enable bits in the CCPTMRSx registers.
For more details, see Register 19-2,
Register 19-3 and Register 20-2
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DS39960C-page 222 2011 Microchip Technology Inc.
TABLE 16-5: REGISTERS ASSOCIATED WITH TIMER3/5/7 AS A TIMER/COUNTER
Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
INTCON GIE/GIEH PEIE/GIEL TMR0IE INT0IE RBIE TMR0IF INT0IF RBIF
PIR5 TMR7GIF(1) TMR12IF(1) TMR10IF(1) TMR8IF TMR7IF(1) TMR6IF TMR5IF TMR4IF
IPR5 TMR7GIP(1) TMR12IP(1) TMR10IP(1) TMR8IP TMR7IP(1) TMR6IP TMR5IP TMR4IP
PIE5 TMR7GIE(1) TMR12IE(1) TMR10IE(1) TMR8IE TMR7IE(1) TMR6IE TMR5IE TMR4IE
PIE3 TMR5GIE —RC2IE TX2IE CTMUIE CCP2IE CCP1IE RTCCIE
IPR3 TMR5GIP —RC2IP TX2IP CTMUIP CCP2IP CCP1IP RTCCIP
PIR3 TMR5GIF —RC2IF TX2IF CTMUIF CCP2IF CCP1IF RTCCIF
PIE2 OSCFIE —SSP2IE BCL2IE BCL1IE HLVDIE TMR3IE TMR3GIE
PIR2 OSCFIF —SSP2IF BCL2IF BCL1IF HLVDIF TMR3IF TMR3GIF
IPR2 OSCFIP —SSP2IP BCL2IP BCL1IP HLVDIP TMR3IP TMR3GIP
TMR3H Timer3 Register High Byte
TMR3L Timer3 Register Low Byte
T3GCON TMR3GE T3GPOL T3GTM T3GSPM T3GGO/
T3DONE
T3GVAL T3GSS1 T3GSS0
T3CON TMR3CS1 TMR3CS0 T3CKPS1 T3CKPS0 SOSCEN T3SYNC RD16 TMR3ON
TMR5H Timer5 Register High Byte
TMR5L Timer5 Register Low Byte
T5GCON TMR5GE T5GPOL T5GTM T5GSPM T5GGO/
T5DONE
T5GVAL T5GSS1 T5GSS0
T5CON TMR5CS1 TMR5CS0 T5CKPS1 T5CKPS0 SOSCEN T5SYNC RD16 TMR5ON
TMR7H(1) Timer7 Register High Byte
TMR7L(1) Timer7 Register Low Byte
T7GCON(1) TMR7GE T7GPOL T7GTM T7GSPM T7GGO/
T7DONE
T7GVAL T7GSS1 T7GSS0
T7CON(1) TMR7CS1 TMR7CS0 T7CKPS1 T7CKPS0 SOSCEN T7SYNC RD16 TMR7ON
OSCCON2 — SOSCRUN ——SOSCGO— MFIOFS MFIOSEL
PMD1 PSPMD CTMUMD RTCCMD TMR4MD TMR3MD TMR2MD TMR1MD EMBMD
PMD2 TMR10MD(1) TMR8MD TMR7MD(1) TMR6MD TMR5MD CMP3MD CMP2MD CMP2MD
Legend: — = unimplemented, read as ‘0’. Shaded cells are not used by the Timer3/5/7 module.
Note 1: Unimplemented on devices with a program memory of 32 Kbytes (PIC18FX5K22).
2011 Microchip Technology Inc. DS39960C-page 223
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17.0 TIMER4/6/8/10/12 MODULES
The Timer4/6/8/10/12 timer modules have the following
features:
• Eight-bit Timer register (TMRx)
• Eight-bit Period register (PRx)
• Readable and writable (all registers)
• Software programmable prescaler (1:1, 1:4, 1:16)
• Software programmable postscaler (1:1 to 1:16)
• Interrupt on TMRx match of PRx
Timer10 and Timer12 are unimplemented for devices
with program memory of 32 Kbytes (PIC18FX5K22).
The Timer4/6/8/10/12 modules have a control register
shown in Register 17-1. Timer4/6/8/10/12 can be shut
off by clearing control bit, TMRxON (TxCON<2>), to
minimize power consumption. The prescaler and post-
scaler selection of Timer4/6/8/10/12 also are controlled
by this register. Figure 17-1 is a simplified block
diagram of the Timer4/6/8/10/12 modules.
17.1 Timer4/6/8/10/12 Operation
Timer4/6/8/10/12 can be used as the PWM time base
for the PWM mode of the ECCP modules. The TMRx
registers are readable and writable, and are cleared on
any device Reset. The input clock (FOSC/4) has a
prescale option of 1:1, 1:4 or 1:16, selected by control
bits, TxCKPS<1:0> (TxCON<1:0>). The match output
of TMRx goes through a four-bit postscaler (that gives
a 1:1 to 1:16 inclusive scaling) to generate a TMRx
interrupt, latched in the flag bit, TMRxIF. Tabl e 1 7-1
gives each module’s flag bit.
The interrupt can be enabled or disabled by setting or
clearing the Timerx Interrupt Enable bit (TMRxIE),
shown in Tab l e 17- 2.
The prescaler and postscaler counters are cleared
when any of the following occurs:
• A write to the TMRx register
• A write to the TxCON register
• Any device Reset – Power-on Reset (POR),
MCLR Reset, Watchdog Timer Reset (WDTR) or
Brown-out Reset (BOR)
A TMRx is not cleared when a TxCON is written.
Note: Throughout this section, generic references
are used for register and bit names that are the
same, except for an ‘x’ variable that indicates
the item’s association with the Timer4, Timer6,
Timer8, Timer10 or Timer12 module. For
example, the control register is named TxCON
and refers to T4CON, T6CON, T8CON,
T10CON and T12CON.
TABLE 17-1: TIMER4/6/8/10/12 FLAG BITS
Timer
Module Flag Bit
PIR5<x> Timer
Module Flag Bit
PIR5<x>
40105
62126
84
TABLE 17-2: TIMER4/6/8/10/12 INTERRUPT
ENABLE BITS
Timer
Module Flag Bit
PIE5<x> Timer
Module Flag Bit
PIE5<x>
40105
62126
84
Note: The CCP and ECCP modules use Timers,
1 through 8, for some modes. The assign-
ment of a particular timer to a CCP/ECCP
module is determined by the Timer to CCP
enable bits in the CCPTMRSx registers.
For more details, see Register 19-2,
Register 19-3 and Register 20-2.
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DS39960C-page 224 2011 Microchip Technology Inc.
17.2 Timer4/6/8/10/12 Inter rupt
The Timer4/6/8/10/12 modules have eight-bit period
registers, PRx, that are both readable and writable.
Timer4/6/8/10/12 increment from 00h until they match
PR4/6/8/10/12 and then reset to 00h on the next
increment cycle. The PRx registers are initialized to
FFh upon Reset.
17.3 Output of TMRx
The outputs of TMRx (before the postscaler) are used
only as a PWM time base for the ECCP modules. They
are not used as baud rate clocks for the MSSP
modules as is the Timer2 output.
FIGURE 17-1: TIMER4 BLOCK DIAGRAM
REGISTER 17-1: TxCON: TIMERx CONTROL REGISTER
U-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0
— TxOUTPS3 TxOUTPS2 TxOUTPS1 TxOUTPS0 TMRxON TxCKPS1 TxCKPS0
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 Unimplemented: Read as ‘0’
bit 6-3 TxOUTPS<3:0>: Timerx Output Postscale Select bits
0000 = 1:1 Postscale
0001 = 1:2 Postscale
•
•
•
1111 = 1:16 Postscale
bit 2 TMRxON: Timerx On bit
1 = Timerx is on
0 = Timerx is off
bit 1-0 TxCKPS<1:0>: Timerx Clock Prescale Select bits
00 = Prescaler is 1
01 = Prescaler is 4
1x = Prescaler is 16
Comparator
TMRx Output
TMRx
Postscaler
Prescaler PRx
2
FOSC/4
1:1 to 1:16
1:1, 1:4, 1:16
4
TxOUTPS<3:0>
TxCKPS<1:0>
Set TMRxIF
Internal Data Bus
8
Reset
TMRx/PRx
8
8
(to PWM)
Match
2011 Microchip Technology Inc. DS39960C-page 225
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TABLE 17-3: REGISTERS ASSOCIATED WITH TIMER4/6/8/10/12 AS A TIMER/COUNTER
Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
INTCON GIE/GIEH PEIE/GIEL TMR0IE INT0IE RBIE TMR0IF INT0IF RBIF
IPR5 TMR7GIP(1) TMR12IP(1) TMR10IP(1) TMR8IP TMR7IP(1) TMR6IP TMR5IP TMR4IP
PIR5 TMR7GIF(1) TMR12IF(1) TMR10IF(1) TMR8IF TMR7IF(1) TMR6IF TMR5IF TMR4IF
PIE5 TMR7GIE(1) TMR12IE(1) TMR10IE(1) TMR8IE TMR7IE(1) TMR6IE TMR5IE TMR4IE
TMR4 Timer4 Register
T4CON — T4OUTPS3 T4OUTPS2 T4OUTPS1 T4OUTPS0 TMR4ON T4CKPS1 T4CKPS0
PR4 Timer4 Period Register
TMR6 Timer6 Register
T6CON — T6OUTPS3 T6OUTPS2 T6OUTPS1 T6OUTPS0 TMR6ON T6CKPS1 T6CKPS0
PR6 Timer6 Period Register
TMR8 Timer8 Register
T8CON — T8OUTPS3 T8OUTPS2 T8OUTPS1 T8OUTPS0 TMR8ON T8CKPS1 T8CKPS0
PR8 Timer8 Period Register
TMR10(1) Timer10 Register
T10CON(1) — T10OUTPS3 T10OUTPS2 T10OUTPS1 T10OUTPS0 TMR10ON T10CKPS1 T10CKPS0
PR10(1) Timer10 Period Register
TMR12(1) Timer12 Register
T12CON(1) — T12OUTPS3 T12OUTPS2 T12OUTPS1 T12OUTPS0 TMR12ON T12CKPS1 T12CKPS0
PR12(1) Timer12 Period Register
PMD1 PSPMD CTMUMD RTCCMD TMR4MD TMR3MD TMR2MD TMR1MD EMBMD
PMD2 TMR10MD(1) TMR8MD TMR7MD(1) TMR6MD TMR5MD CMP3MD CMP2MD CMP2MD
PMD3 CCP10MD(1) CCP9MD(1) CCP8MD CCP7MD CCP6MD CCP5MD CCP4MD TMR12MD(1)
Legend: — = unimplemented, read as ‘0’. Shaded cells are not used by the Timer4/6/8/10/12 module.
Note 1: Unimplemented on devices with a program memory of 32 Kbytes (PIC18FX5K22).
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NOTES:
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18.0 REAL-TIME CLOCK AND
CALENDAR (RTCC)
The key features of the Real-Time Clock and Calendar
(RTCC) module are:
• Time: hours, minutes and seconds
• Twenty-four hour format (military time)
• Calendar: weekday, date, month and year
• Alarm configurable
• Year range: 2000 to 2099
• Leap year correction
• BCD format for compact firmware
• Optimized for low-power operation
• User calibration with auto-adjust
• Calibration range: 2.64 seconds error per month
• Requirements: external 32.768 kHz clock crystal
• Alarm pulse or seconds clock output on RTCC pin
The RTCC module is intended for applications where
accurate time must be maintained for extended period
with minimum to no intervention from the CPU. The
module is optimized for low-power usage in order to
provide extended battery life while keeping track of
time.
The module is a 100-year clock and calendar with auto-
matic leap year detection. The range of the clock is
from 00:00:00 (midnight) on January 1, 2000 to
23:59:59 on December 31, 2099.
Hours are measured in 24-hour (military time) format.
The clock provides a granularity of one second with
half-second visibility to the user.
FIGURE 18-1: RTCC BLOCK DIAGRAM
RTCC Prescalers
RTCC Timer
Comparator
Compare Registers
Repeat Counter
YEAR
MTHDY
WKDYHR
MINSEC
ALMTHDY
ALWDHR
ALMINSEC
with Masks
RTCC Interrupt Logic
RTCCFG
ALRMRPT
Alarm
Event
0.5s
RTCC Clock Domain
Alarm Pulse
RTCC Interrupt
CPU Clock Domain
RTCVALx
ALRMVALx
RTCC Pin
RTCOE
32.768 kHz Input
from SOSC Oscillator
Internal RC
(LF-INTOSC)
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DS39960C-page 228 2011 Microchip Technology Inc.
18.1 RTCC MODULE REGISTERS
The RTCC module registers are divided into the
following categories:
RTCC Control Registers
• RTCCFG
• RTCCAL
• PADCFG1
•ALRMCFG
•ALRMRPT
RTCC Value Registers
•RTCVALH
•RTCVALL
Both registers access the following registers:
- YEAR
-MONTH
-DAY
- WEEKDAY
-HOUR
- MINUTE
- SECOND
Alarm Value Registers
•ALRMVALH
• ALRMVALL
Both registers access the following registers:
- ALRMMNTH
-ALRMDAY
-ALRMWD
-ALRMHR
- ALRMMIN
- ALRMSEC
Note: The RTCVALH and RTCVALL registers
can be accessed through RTCRPT<1:0>
(RTCCFG<1:0>). ALRMVALH and
ALRMVALL can be accessed through
ALRMPTR<1:0> (ALRMCFG<1:0>).
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18.1.1 RTCC CONTROL REGISTERS
REGISTER 18-1: RTCCFG: RTCC CONFIGURATION REGISTER(1)
R/W-0 U-0 R/W-0 R-0 R-0 R/W-0 R/W-0 R/W-0
RTCEN(2) —RTCWREN
(4) RTCSYNC HALFSEC(3) RTCOE RTCPTR1 RTCPTR0
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 RTCEN: RTCC Enable bit(2)
1 = RTCC module is enabled
0 = RTCC module is disabled
bit 6 Unimplemented: Read as ‘0’
bit 5 RTCWREN: RTCC Value Registers Write Enable bit(4)
1 = RTCVALH and RTCVALL registers can be written to by the user
0 = RTCVALH and RTCVALL registers are locked out from being written to by the user
bit 4 RTCSYNC: RTCC Value Registers Read Synchronization bit
1 = RTCVALH, RTCVALL and ALRMRPT registers can change while reading if a rollover ripple
results in an invalid data read. If the register is read twice and results in the same data, the data
can be assumed to be valid.
0 = RTCVALH, RTCVALL and ALCFGRPT registers can be read without concern over a rollover
ripple
bit 3 HALFSEC: Half-Second Status bit(3)
1 = Second half period of a second
0 = First half period of a second
bit 2 RTCOE: RTCC Output Enable bit
1 = RTCC clock output enabled
0 = RTCC clock output disabled
bit 1-0 RTCPTR<1:0>: RTCC Value Register Window Pointer bits
Points to the corresponding RTCC Value registers when reading the RTCVALH and RTCVALL
registers. The RTCPTR<1:0> value decrements on every read or write of RTCVALH<15:8> until it
reaches ‘00’.
RTCVALH:
00 = Minutes
01 = Weekday
10 = Month
11 = Reserved
RTCVALL:
00 = Seconds
01 = Hours
10 = Day
11 = Year
Note 1: The RTCCFG register is only affected by a POR.
2: A write to the RTCEN bit is only allowed when RTCWREN = 1.
3: This bit is read-only; it is cleared to ‘0’ on a write to the lower half of the MINSEC register.
4: RTCWREN can only be written with the unlock sequence (see Example 18-1).
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REGISTER 18-2: RTCCAL: RTCC CALIBRATION REGISTER
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0
CAL7 CAL6 CAL5 CAL4 CAL3 CAL2 CAL1 CAL0
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7-0 CAL<7:0>: RTC Drift Calibration bits
01111111 = Maximum positive adjustment. Adds 508 RTC clock pulses every minute.
.
.
.
00000001 = Minimum positive adjustment. Adds four RTC clock pulses every minute.
00000000 = No adjustment
11111111 = Minimum negative adjustment. Subtracts four RTC clock pulses every minute.
.
.
.
10000000 = Maximum negative adjustment. Subtracts 512 RTC clock pulses every minute.
REGISTER 18-3: PADCFG1: PAD CONFIGURATION REGISTER
R/W-0 R/W-0 R/W-0 U-0 U-0 R/W-0 R/W-0 U-0
RDPU REPU RJPU(2) — — RTSECSEL1(1) RTSECSEL0(1) —
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 RDPU: PORTD Pull-up Enable bit
1 = PORTD pull-up resistors are enabled by individual port latch values
0 = All PORTD pull-up resistors are disabled
bit 6 REPU: PORTE Pull-up Enable bit
1 = PORTE pull-up resistors are enabled by individual port latch values
0 = All PORTE pull-up resistors are disabled
bit 5 RJPU: PORTJ Pull-up Enable bit(2)
1 = PORTJ pull-up resistors are enabled by individual port latch values
0 = All PORTJ pull-up resistors are disabled
bit 2-1 RTSECSEL<1:0>: RTCC Seconds Clock Output Select bit(1)
11 = Reserved; do not use
10 = RTCC source clock is selected for the RTCC pin (pin can be LF-INTOSC or SOSC, depending on
the RTCOSC (CONFIG3L<1>) bit setting)
01 = RTCC seconds clock is selected for the RTCC pin
00 = RTCC alarm pulse is selected for the RTCC pin
bit 0 Unimplemented: Read as ‘0’
Note 1: To enable the actual RTCC output, the RTCOE (RTCCFG<2>) bit must be set.
2: Unimplemented on 64-pin devices (PIC18F6XK22), read as ‘0’.
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REGISTER 18-4: ALRMCFG: ALARM CONFIGURATION REGISTER
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0
ALRMEN CHIME AMASK3 AMASK2 AMASK1 AMASK0 ALRMPTR1 ALRMPTR0
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 ALRMEN: Alarm Enable bit
1 = Alarm is enabled (cleared automatically after an alarm event whenever ARPT<7:0> = 00
and CHIME = 0)
0 = Alarm is disabled
bit 6 CHIME: Chime Enable bit
1 = Chime is enabled; ALRMPTR<1:0> bits are allowed to roll over from 00h to FFh
0 = Chime is disabled; ALRMPTR<1:0> bits stop once they reach 00h
bit 5-2 AMASK<3:0>: Alarm Mask Configuration bits
0000 = Every half second
0001 = Every second
0010 = Every 10 seconds
0011 = Every minute
0100 = Every 10 minutes
0101 = Every hour
0110 = Once a day
0111 = Once a week
1000 = Once a month
1001 = Once a year (except when configured for February 29th, once every four years)
101x = Reserved – Do not use
11xx = Reserved – Do not use
bit 1-0 ALRMPTR<1:0>: Alarm Value Register Window Pointer bits
Points to the corresponding Alarm Value registers when reading the ALRMVALH and ALRMVALL
registers. The ALRMPTR<1:0> value decrements on every read or write of ALRMVALH until it reaches
‘00’.
ALRMVALH:
00 = ALRMMIN
01 =ALRMWD
10 =ALRMMNTH
11 = Unimplemented
ALRMVALL:
00 = ALRMSEC
01 =ALRMHR
10 =ALRMDAY
11 = Unimplemented
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18.1.2 RTCVALH AND RTCVALL
REGISTER MAPPINGS
REGISTER 18-5: ALRMRPT: ALARM REPEAT REGISTER
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0
ARPT7 ARPT6 ARPT5 ARPT4 ARPT3 ARPT2 ARPT1 ARPT0
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7-0 ARPT<7:0>: Alarm Repeat Counter Value bits
11111111 = Alarm will repeat 255 more times
.
.
.
00000000 = Alarm will not repeat
The counter decrements on any alarm event. The counter is prevented from rolling over from 00h to
FFh unless CHIME = 1.
REGISTER 18-6: RESERVED REGISTER
U-0 U-0 U-0 U-0 U-0 U-0 U-0 U-0
— — — — — — — —
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7-0 Unimplemented: Read as ‘0’
REGISTER 18-7: YEAR: YEAR VALUE REGISTER(1)
R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x
YRTEN3 YRTEN2 YRTEN1 YRTEN0 YRONE3 YRONE2 YRONE1 YRONE0
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7-4 YRTEN<3:0>: Binary Coded Decimal Value of Year’s Tens Digit bits
Contains a value from 0 to 9.
bit 3-0 YRONE<3:0>: Binary Coded Decimal Value of Year’s Ones Digit bits
Contains a value from 0 to 9.
Note 1: A write to the YEAR register is only allowed when RTCWREN = 1.
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REGISTER 18-8: MONTH: MONTH VALUE REGISTER(1)
U-0 U-0 U-0 R/W-x R/W-x R/W-x R/W-x R/W-x
— — — MTHTEN0 MTHONE3 MTHONE2 MTHONE1 MTHONE0
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7-5 Unimplemented: Read as ‘0’
bit 4 MTHTEN0: Binary Coded Decimal Value of Month’s Tens Digit bit
Contains a value of 0 or 1.
bit 3-0 MTHONE<3:0>: Binary Coded Decimal Value of Month’s Ones Digit bits
Contains a value from 0 to 9.
Note 1: A write to this register is only allowed when RTCWREN = 1.
REGISTER 18-9: DAY: DAY VA LUE REGISTER (1)
U-0 U-0 R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x
—— DAYTEN1 DAYTEN0 DAYONE3 DAYONE2 DAYONE1 DAYONE0
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7-6 Unimplemented: Read as ‘0’
bit 5-4 DAYTEN<1:0>: Binary Coded Decimal value of Day’s Tens Digit bits
Contains a value from 0 to 3.
bit 3-0 DAYONE<3:0>: Binary Coded Decimal Value of Day’s Ones Digit bits
Contains a value from 0 to 9.
Note 1: A write to this register is only allowed when RTCWREN = 1.
REGISTER 18-10: WEEKDAY: WEEKDAY VALUE REGISTER(1)
U-0 U-0 U-0 U-0 U-0 R/W-x R/W-x R/W-x
— — — — — WDAY2 WDAY1 WDAY0
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7-3 Unimplemented: Read as ‘0’
bit 2-0 WDAY<2:0>: Binary Coded Decimal Value of Weekday Digit bits
Contains a value from 0 to 6.
Note 1: A write to this register is only allowed when RTCWREN = 1.
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REGISTER 18-11: HOUR: HOUR VALUE REGISTER(1)
U-0 U-0 R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x
—— HRTEN1 HRTEN0 HRONE3 HRONE2 HRONE1 HRONE0
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7-6 Unimplemented: Read as ‘0’
bit 5-4 HRTEN<1:0>: Binary Coded Decimal Value of Hour’s Tens Digit bits
Contains a value from 0 to 2.
bit 3-0 HRONE<3:0>: Binary Coded Decimal Value of Hour’s Ones Digit bits
Contains a value from 0 to 9.
Note 1: A write to this register is only allowed when RTCWREN = 1.
REGISTER 18-12: MINUTE: MINUTE VALUE REGISTER
U-0 R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x
— MINTEN2 MINTEN1 MINTEN0 MINONE3 MINONE2 MINONE1 MINONE0
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 Unimplemented: Read as ‘0’
bit 6-4 MINTEN<2:0>: Binary Coded Decimal Value of Minute’s Tens Digit bits
Contains a value from 0 to 5.
bit 3-0 MINONE<3:0>: Binary Coded Decimal Value of Minute’s Ones Digit bits
Contains a value from 0 to 9.
REGISTER 18-13: SECOND: SECOND VALUE REGISTER
U-0 R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x
— SECTEN2 SECTEN1 SECTEN0 SECONE3 SECONE2 SECONE1 SECONE0
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 Unimplemented: Read as ‘0’
bit 6-4 SECTEN<2:0>: Binary Coded Decimal Value of Second’s Tens Digit bits
Contains a value from 0 to 5.
bit 3-0 SECONE<3:0>: Binary Coded Decimal Value of Second’s Ones Digit bits
Contains a value from 0 to 9.
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18.1.3 ALRMVALH AND ALRMVALL
REGISTER MAPPINGS
REGISTER 18-14: ALRMMNTH: ALARM MONTH VALUE REGISTER(1)
U-0 U-0 U-0 R/W-x R/W-x R/W-x R/W-x R/W-x
— — — MTHTEN0 MTHONE3 MTHONE2 MTHONE1 MTHONE0
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7-5 Unimplemented: Read as ‘0’
bit 4 MTHTEN0: Binary Coded Decimal Value of Month’s Tens Digit bits
Contains a value of 0 or 1.
bit 3-0 MTHONE<3:0>: Binary Coded Decimal Value of Month’s Ones Digit bits
Contains a value from 0 to 9.
Note 1: A write to this register is only allowed when RTCWREN = 1.
REGISTER 18-15: ALRMDAY: ALARM DAY VALUE REGISTER(1)
U-0 U-0 R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x
—— DAYTEN1 DAYTEN0 DAYONE3 DAYONE2 DAYONE1 DAYONE0
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7-6 Unimplemented: Read as ‘0’
bit 5-4 DAYTEN<1:0>: Binary Coded Decimal Value of Day’s Tens Digit bits
Contains a value from 0 to 3.
bit 3-0 DAYONE<3:0>: Binary Coded Decimal Value of Day’s Ones Digit bits
Contains a value from 0 to 9.
Note 1: A write to this register is only allowed when RTCWREN = 1.
REGISTER 18-16: ALRMWD: ALARM WEEKDAY VALUE REGISTER(1)
U-0 U-0 U-0 U-0 U-0 R/W-x R/W-x R/W-x
— — — — — WDAY2 WDAY1 WDAY0
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7-3 Unimplemented: Read as ‘0’
bit 2-0 WDAY<2:0>: Binary Coded Decimal Value of Weekday Digit bits
Contains a value from 0 to 6.
Note 1: A write to this register is only allowed when RTCWREN = 1.
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REGISTER 18-17: ALRMHR: ALARM HOURS VALUE REGISTER(1)
U-0 U-0 R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x
—— HRTEN1 HRTEN0 HRONE3 HRONE2 HRONE1 HRONE0
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7-6 Unimplemented: Read as ‘0’
bit 5-4 HRTEN<1:0>: Binary Coded Decimal Value of Hour’s Tens Digit bits
Contains a value from 0 to 2.
bit 3-0 HRONE<3:0>: Binary Coded Decimal Value of Hour’s Ones Digit bits
Contains a value from 0 to 9.
Note 1: A write to this register is only allowed when RTCWREN = 1.
REGISTER 18-18: ALRMMIN: ALARM MINUTES VALUE REGISTER
U-0 R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x
— MINTEN2 MINTEN1 MINTEN0 MINONE3 MINONE2 MINONE1 MINONE0
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 Unimplemented: Read as ‘0’
bit 6-4 MINTEN<2:0>: Binary Coded Decimal Value of Minute’s Tens Digit bits
Contains a value from 0 to 5.
bit 3-0 MINONE<3:0>: Binary Coded Decimal Value of Minute’s Ones Digit bits
Contains a value from 0 to 9.
REGISTER 18-19: ALRMSEC: ALARM SECONDS VALUE REGISTER
U-0 R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x
— SECTEN2 SECTEN1 SECTEN0 SECONE3 SECONE2 SECONE1 SECONE0
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 Unimplemented: Read as ‘0’
bit 6-4 SECTEN<2:0>: Binary Coded Decimal Value of Second’s Tens Digit bits
Contains a value from 0 to 5.
bit 3-0 SECONE<3:0>: Binary Coded Decimal Value of Second’s Ones Digit bits
Contains a value from 0 to 9.
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18.1.4 RTCEN BIT WRITE
RTCWREN (RTCCFG<5>) must be set before a write
to RTCEN can take place. Any write to the RTCEN bit,
while RTCWREN = 0, will be ignored.
Like the RTCEN bit, the RTCVALH and RTCVALL
registers can only be written to when RTCWREN = 1.
A write to these registers, while RTCWREN = 0, will be
ignored.
18.2 Operation
18.2.1 REGISTER INTERFACE
The register interface for the RTCC and alarm values is
implemented using the Binary Coded Decimal (BCD)
format. This simplifies the firmware when using the
module, as each of the digits is contained within its own
4-bit value (see Figure 18-2 and Figure 18-3).
FIGURE 18-2: TIMER DIGIT FORMAT
FIGURE 18-3: ALARM DIGIT FORMAT
0-60-9 0-9 0-3 0-9
0-9 0-9 0-90-2 0-5 0-5 0/1
Day Of WeekYear Day
Hours
(24-hour format) Minutes Seconds 1/2 Second Bit
0-1 0-9
Month
(binary format)
0-60-3 0-9
0-9 0-9 0-90-2 0-5 0-5
Day Of WeekDay
Hours
(24-hour format) Minutes Seconds
0-1 0-9
Month
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18.2.2 CLOCK SOURCE
As mentioned earlier, the RTCC module is intended to
be clocked by an external Real-Time Clock crystal
oscillating at 32.768 kHz, but an internal oscillator can
be used. The RTCC clock selection is decided by the
RTCOSC bit (CONFIG3L<0>).
Calibration of the crystal can be done through this
module to yield an error of 3 seconds or less per month.
(For further details, see Section 18.2.9 “Calibration”.)
FIGURE 18-4: CLOCK SOURCE MULTIP LEXING
18.2.2.1 Real-Time Clock Enable
The RTCC module can be clocked by an external,
32.768 kHz crystal (SOSC oscillator) or the LF-INTOSC
oscillator, which can be selected in CONFIG3L<0>.
If the external clock is used, the SOSC oscillator should
be enabled. If LF-INTOSC is providing the clock, the
INTOSC clock can be brought out to the RTCC pin by
the RTSECSEL<1:0> bits (PADCFG<2:1>).
18.2.3 DIGIT CARRY RULES
This section explains which timer values are affected
when there is a rollover:
• Time of Day: From 23:59:59 to 00:00:00 with a
carry to the Day field
• Month: From 12/31 to 01/01 with a carry to the
Year field
• Day of Week: From 6 to 0 with no carry (see
Table 18-1)
• Year Carry: From 99 to 00; this also surpasses the
use of the RTCC
For the day-to-month rollover schedule, see Table 18-2.
Because the following values are in BCD format, the
carry to the upper BCD digit occurs at the count of 10,
not 16 (SECONDS, MINUTES, HOURS, WEEKDAY,
DAYS and MONTHS).
TABLE 18-1: DAY OF WEEK SCHEDULE
TABLE 18-2: DAY TO MONTH ROLLOVER
SCHEDULE
Note 1: Writing to the lower half of the MINSEC register resets all counters, allowing fraction of a second synchronization;
clock prescaler is held in Reset when RTCEN = 0.
32.768 kHz XTAL
1:16384
Half second(1)
Half-Second
Clock One Second Clock
Year
Month
Day
Day of Week
Second Hour:Minute
Clock Prescaler(1)
from SOSC
Internal RC
RTCCFG
Day of Week
Sunday 0
Monday 1
Tuesday 2
Wednesday 3
Thursday 4
Friday 5
Saturday 6
Month Maximum Day Field
01 (January) 31
02 (February) 28 or 29(1)
03 (March) 31
04 (April) 30
05 (May) 31
06 (June) 30
07 (July) 31
08 (August) 31
09 (September) 30
10 (October) 31
11 (November) 30
12 (December) 31
Note 1: See Section 18.2.4 “Le ap Year”.
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18.2.4 LEAP YEAR
Since the year range on the RTCC module is 2000 to
2099, the leap year calculation is determined by any year
divisible by four in the above range. Only February is
affected in a leap year.
February will have 29 days in a leap year and 28 days in
any other year.
18.2.5 GENERAL FUNCTIONALITY
All Timer registers containing a time value of seconds or
greater are writable. The user configures the time by
writing the required year, month, day, hour, minutes and
seconds to the Timer registers, via register pointers.
(See Section 18.2.8 “Register Mapping”.)
The timer uses the newly written values and proceeds
with the count from the required starting point.
The RTCC is enabled by setting the RTCEN bit
(RTCCFG<7>). If enabled while adjusting these
registers, the timer still continues to increment. However,
any time the MINSEC register is written to, both of the
timer prescalers are reset to ‘0’. This allows fraction of a
second synchronization.
The Timer registers are updated in the same cycle as
the write instruction’s execution by the CPU. The user
must ensure that when RTCEN = 1, the updated
registers will not be incremented at the same time. This
can be accomplished in several ways:
• By checking the RTCSYNC bit (RTCCFG<4>)
• By checking the preceding digits from which a
carry can occur
• By updating the registers immediately following
the seconds pulse (or an alarm interrupt)
The user has visibility to the half-second field of the
counter. This value is read-only and can be reset only
by writing to the lower half of the SECONDS register.
18.2.6 SAFETY WINDOW FOR REGISTER
READS AND WRITES
The RTCSYNC bit indicates a time window during
which the RTCC clock domain registers can be safely
read and written without concern about a rollover.
When RTCSYNC = 0, the registers can be safely
accessed by the CPU.
Whether RTCSYNC = 1 or 0, the user should employ a
firmware solution to ensure that the data read did not
fall on a rollover boundary, resulting in an invalid or
partial read. This firmware solution would consist of
reading each register twice and then comparing the two
values. If the two values matched, then a rollover did
not occur.
18.2.7 WRITE LOCK
In order to perform a write to any of the RTCC Timer
registers, the RTCWREN bit (RTCCFG<5>) must be set.
To avoid accidental writes to the RTCC Timer register,
it is recommended that the RTCWREN bit
(RTCCFG<5>) be kept clear when not writing to the
register. For the RTCWREN bit to be set, there is only
one instruction cycle time window allowed between the
55h/AA sequence and the setting of RTCWREN. For
that reason, it is recommended that users follow the
code example in Example 18-1.
EXAMPLE 18-1: SETTING THE RTCWREN
BIT
18.2.8 REGISTER MAPPING
To limit the register interface, the RTCC Timer and
Alarm Timer registers are accessed through
corresponding register pointers. The RTCC Value
register window (RTCVALH and RTCVALL) uses the
RTCPTRx bits (RTCCFG<1:0>) to select the required
Timer register pair.
By reading or writing to the RTCVALH register, the
RTCC Pointer value (RTCPTR<1:0>) decrements by ‘1’
until it reaches ‘00’. When ‘00’ is reached, the
MINUTES and SECONDS value is accessible through
RTCVALH and RTCVALL until the pointer value is
manually changed.
TABLE 18-3: RTCVALH AND RTCVALL
REGISTER MAPPING
The Alarm Value register windows (ALRMVALH and
ALRMVALL) use the ALRMPTR bits (ALRMCFG<1:0>)
to select the desired alarm register pair.
By reading or writing to the ALRMVALH register, the
Alarm Pointer value, ALRMPTR<1:0>, decrements by ‘1’
until it reaches ‘00’. When it reaches ‘00’, the ALRMMIN
and ALRMSEC values are accessible through
ALRMVALH and ALRMVALL until the pointer value is
manually changed.
movlw 0x55
movwf EECON2
movlw 0xAA
movwf EECON2
bsf RTCCFG,RTCWREN
RTCPTR<1:0> RTCC Value Register Window
RTCVALH RTCVALL
00 MINUTES SECONDS
01 WEEKDAY HOURS
10 MONTH DAY
11 — YEAR
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TABLE 18-4: ALRMVAL REGISTER
MAPPING
18.2.9 CALIBRATION
The real-time crystal input can be calibrated using the
periodic auto-adjust feature. When properly calibrated,
the RTCC can provide an error of less than three
seconds per month.
To perform this calibration, find the number of error
clock pulses and store the value into the lower half of
the RTCCAL register. The eight-bit, signed value,
loaded into RTCCAL, is multiplied by four and will be
either added or subtracted from the RTCC timer, once
every minute.
To calibrate the RTCC module:
1. Use another timer resource on the device to find
the error of the 32.768 kHz crystal.
2. Convert the number of error clock pulses per
minute (see Equation 18-1).
• If the oscillator is faster than ideal (negative
result from Step 2), the RCFGCALL register
value needs to be negative. This causes the
specified number of clock pulses to be
subtracted from the timer counter once every
minute.
• If the oscillator is slower than ideal (positive
result from Step 2), the RCFGCALL register
value needs to be positive. This causes the
specified number of clock pulses to be added to
the timer counter once every minute.
3. Load the RTCCAL register with the correct
value.
Writes to the RTCCAL register should occur only when
the timer is turned off or immediately after the rising
edge of the seconds pulse.
18.3 Alarm
The Alarm features and characteristics are:
• Configurable from half a second to one year
• Enabled using the ALRMEN bit (ALRMCFG<7>,
Register 18-4)
• Offers one-time and repeat alarm options
18.3.1 CONFIGURING THE ALARM
The alarm feature is enabled using the ALRMEN bit.
This bit is cleared when an alarm is issued. The bit will
not be cleared if the CHIME bit = 1 or if ALRMRPT 0.
The interval selection of the alarm is configured
through the ALRMCFG bits (AMASK<3:0>); see
Figure 18-5. These bits determine which and how
many digits of the alarm must match the clock value for
the alarm to occur.
The alarm can also be configured to repeat based on a
preconfigured interval. The number of times this
occurs, after the alarm is enabled, is stored in the
ALRMRPT register.
ALRMPTR<1:0> Alarm Value Register Wi ndow
ALRMVALH ALRMVALL
00 ALRMMIN ALRMSEC
01 ALRMWD ALRMHR
10 ALRMMNTH ALRMDAY
11 ——
EQUATION 18-1: CONVERTING ERROR
CLOCK PULSES
(Ideal Frequency (32,758) – Measured Frequency) * 60 =
Error Clocks per Minute
Note: In determining the crystal’s error value, it
is the user’s responsibility to include the
crystal’s initial error from drift due to
temperature or crystal aging.
Note: While the alarm is enabled (ALRMEN = 1),
changing any of the registers, other than
the RTCCAL, ALRMCFG and ALRMRPT
registers and the CHIME bit, can result in a
false alarm event leading to a false alarm
interrupt. To avoid this, only change the
timer and alarm values while the alarm is
disabled (ALRMEN = 0). It is recom-
mended that the ALRMCFG and
ALRMRPT registers and CHIME bit be
changed when RTCSYNC = 0.
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FIGURE 18-5: ALARM MAS K SETTINGS
When ALRMCFG = 00 and the CHIME bit = 0
(ALRMCFG<6>), the repeat function is disabled and
only a single alarm will occur. The alarm can be
repeated up to 255 times by loading the ALRMRPT
register with FFh.
After each alarm is issued, the ALRMRPT register is
decremented by one. Once the register has reached
‘00’, the alarm will be issued one last time.
After the alarm is issued a last time, the ALRMEN bit is
cleared automatically and the alarm turned off. Indefinite
repetition of the alarm can occur if the CHIME bit = 1.
When CHIME = 1, the alarm is not disabled when the
ALRMRPT register reaches ‘00’, but it rolls over to FF
and continues counting indefinitely.
18.3.2 ALARM INTERRUPT
At every alarm event, an interrupt is generated. Addi-
tionally, an alarm pulse output is provided that operates
at half the frequency of the alarm.
The alarm pulse output is completely synchronous with
the RTCC clock and can be used as a trigger clock to
other peripherals. This output is available on the RTCC
pin. The output pulse is a clock with a 50% duty cycle
and a frequency half that of the alarm event (see
Figure 18-6).
The RTCC pin also can output the seconds clock. The
user can select between the alarm pulse, generated by
the RTCC module, or the seconds clock output.
The RTSECSEL<1:0> bits (PADCFG1<2:1>) select
between these two outputs:
• Alarm pulse – RTSECSEL<1:0> = 00
• Seconds clock – RTSECSEL<1:0> = 01
Note 1: Annually, except when configured for February 29.
s
ss
mss
mm s s
hh mm ss
dhhmmss
dd hh mm ss
mm d d h h mm s s
Day of the
Week Month Day Hours Minutes Seconds
Alarm Mask Setting
AMASK<3:0>
0000 – Every half second
0001 – Every second
0010 – Every 10 seconds
0011 – Every minute
0100 – Every 10 minutes
0101 – Every hour
0110 – Every day
0111 – Every week
1000 – Every month
1001 – Every year(1)
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FIGURE 18-6: TIMER PULSE GENERATION
18.4 Sleep Mode
The timer and alarm continue to operate while in Sleep
mode. The operation of the alarm is not affected by
Sleep, as an alarm event can always wake up the CPU.
The Idle mode does not affect the operation of the timer
or alarm.
18.5 Reset
18.5.1 DEVICE RESET
When a device Reset occurs, the ALRMRPT register is
forced to its Reset state causing the alarm to be
disabled (if enabled prior to the Reset). If the RTCC
was enabled, it will continue to operate when a basic
device Reset occurs.
18.5.2 POWER-ON RESET (POR)
The RTCCFG and ALRMRPT registers are reset only
on a POR. Once the device exits the POR state, the
clock registers should be reloaded with the desired
values.
The timer prescaler values can be reset only by writing
to the SECONDS register. No device Reset can affect
the prescalers.
RTCEN bit
ALRMEN bit
RTCC Alarm Event
RTCC Pin
2011 Microchip Technology Inc. DS39960C-page 243
PIC18F87K22 FAMILY
18.6 Register Maps
Table 18-5, Tabl e 1 8-6 and Table 18-7 summarize the
registers associated with the RTCC module.
TABLE 18-5: RTCC CONTROL REGISTERS
File Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
RTCCFG RTCEN — RTCWREN RTCSYNC HALFSEC RTCOE RTCPTR1 RTCPTR0
RTCCAL CAL7 CAL6 CAL5 CAL4 CAL3 CAL2 CAL1 CAL0
PADCFG1 RDPU REPU RJPU(1) —— RTSECSEL1 RTSECSEL0 —
ALRMCFG ALRMEN CHIME AMASK3 AMASK2 AMASK1 AMASK0 ALRMPTR1 ALRMPTR0
ALRMRPT ARPT7 ARPT6 ARPT5 ARPT4 ARPT3 ARPT2 ARPT1 ARPT0
PMD1 PSPMD CTMUMD RTCCMD TMR4MD TMR3MD TMR2MD TMR1MD EMBDM
Legend: — = unimplemented, read as ‘0’. Reset values are shown in hexadecimal for 80-pin devices.
Note 1: Unimplemented on 64-pin devices (PIC18F6XK22), read as ‘0’.
TABLE 18-6: RTCC VALUE REGISTERS
File Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
RTCVALH RTCC Value High Register Window Based on RTCPTR<1:0>
RTCVALL RTCC Value Low Register Window Based on RTCPTR<1:0>
TABLE 18-7: ALARM VALUE REGISTERS
File Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
ALRMVALH Alarm Value High Register Window Based on ALRMPTR<1:0>
ALRMVALL Alarm Value Low Register Window Based on ALRMPTR<1:0>
PIC18F87K22 FAMILY
DS39960C-page 244 2011 Microchip Technology Inc.
NOTES:
2011 Microchip Technology Inc. DS39960C-page 245
PIC18F87K22 FAMILY
19.0 CAPTURE/COMPARE/PWM
(CCP) MODULES
PIC18F87K22 family devices have seven CCP
(Capture/Compare/PWM) modules, designated CCP4
through CCP10. All the modules implement standard
Capture, Compare and Pulse-Width Modulation (PWM)
modes.
Each CCP module contains a 16-bit register that can
operate as a 16-bit Capture register, a 16-bit Compare
register or a PWM Master/Slave Duty Cycle register.
For the sake of clarity, all CCP module operation in the
following sections is described with respect to CCP4,
but is equally applicable to CCP5 through CCP10.
Note: Throughout this section, generic references
are used for register and bit names that are
the same, except for an ‘x’ variable that
indicates the item’s association with the
specific CCP module. For example, the
control register is named CCPxCON and
refers to CCP4CON through CCP10CON.
Note: The CCP9 and CCP10 modules are
disabled on the devices with 32 Kbytes of
program memory (PIC18FX5K22).
REGISTER 19-1: CCPxCON: CCPx CONTROL REGISTER (CCP4-CCP10 MODULES)(1)
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0
PxM1 PxM0 DCxB1 DCxB0 CCPxM3(2) CCPxM2(2) CCPxM1(2) CCPxM0(2)
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7-6 PxM<1:0>: PWM Output Configuration bits
If CCPxM<3:2> = 00, 01, 10:
xx = PxA is assigned as a capture/compare input/output; PxB, PxC and PxD are assigned as port pins
If CCPxM<3:2> = 11:
00 = Single output: PxA, PxB, PxC and PxD are controlled by steering
01 = Full-bridge output forward: PxD is modulated; PxA is active; PxB, PxC are inactive
10 = Half-bridge output: PxA, PxB are modulated with dead-band control; PxC and PxD are assigned
as port pins
11 = Full-bridge output reverse: PxB is modulated; PxC is active; PxA and PxD are inactive
bit 5-4 DCxB<1:0>: PWM Duty Cycle bit 1 and bit 0 for CCPx Module
Capture mode:
Unused.
Compare mode:
Unused.
PWM mode:
These bits are the two Least Significant bits (bit 1 and bit 0) of the 10-bit PWM duty cycle. The eight
Most Significant bits (DCx<9:2>) of the duty cycle are found in CCPRxL.
Note 1: The CCP9 and CCP10 modules are not available on the devices with 32 Kbytes of program memory
(PIC18FX5K22).
2: CCPxM<3:0> = 1011 will only reset the timer and not start A/D conversion on CCPx match.
PIC18F87K22 FAMILY
DS39960C-page 246 2011 Microchip Technology Inc.
bit 3-0 CCPxM<3:0>: CCPx Module Mode Select bits(2)
0000 = Capture/Compare/PWM disabled (resets CCPx module)
0001 = Reserved
0010 = Compare mode, toggle output on match (CCPxIF bit is set)
0011 = Reserved
0100 = Capture mode: every falling edge
0101 = Capture mode: every rising edge
0110 = Capture mode: every 4th rising edge
0111 = Capture mode: every 16th rising edge
1000 = Compare mode: initialize CCPx pin low; on compare match, force CCPx pin high (CCPxIF bit is set)
1001 = Compare mode: initialize CCPx pin high; on compare match, force CCPx pin low (CCPxIF bit is set)
1010 = Compare mode: generate software interrupt on compare match (CCPxIF bit is set, CCPx pin
reflects I/O state)
1011 = Compare mode: Special Event Trigger; reset timer on CCPx match (CCPxIF bit is set)
11xx =PWM mode
REGISTER 19-2: CCPTMRS1: CCP TIMER SELECT REGISTER 1
R/W-0 R/W-0 U-0 R/W-0 U-0 R/W-0 R/W-0 R/W-0
C7TSEL1 C7TSEL0 — C6TSEL0 — C5TSEL0 C4TSEL1 C4TSEL0
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7-6 C7TSEL<1:0>: CCP7 Timer Selection bits
00 = CCP7 is based off of TMR1/TMR2
01 = CCP7 is based off of TMR5/TMR4
10 = CCP7 is based off of TMR5/TMR6
11 = CCP7 is based off of TMR5/TMR8
bit 5 Unimplemented: Read as ‘0’
bit 4 C6TSEL0: CCP6 Timer Selection bit
0 = CCP6 is based off of TMR1/TMR2
1 = CCP6 is based off of TMR5/TMR2
bit 3 Unimplemented: Read as ‘0’
bit 2 C5TSEL0: CCP5 Timer Selection bit
0 = CCP5 is based off of TMR1/TMR2
1 = CCP5 is based off of TMR5/TMR4
bit 1-0 C4TSEL<1:0>: CCP4 Timer Selection bits
00 = CCP4 is based off of TMR1/TMR2
01 = CCP4 is based off of TMR3/TMR4
10 = CCP4 is based off of TMR3/TMR6
11 = Reserved; do not use
REGISTER 19-1: CCPxCON: CCPx CONTROL REGISTER (CCP4-CCP10 MODULES)(1)
Note 1: The CCP9 and CCP10 modules are not available on the devices with 32 Kbytes of program memory
(PIC18FX5K22).
2: CCPxM<3:0> = 1011 will only reset the timer and not start A/D conversion on CCPx match.
2011 Microchip Technology Inc. DS39960C-page 247
PIC18F87K22 FAMILY
REGISTER 19-3: CCPTMRS2: CCP TIMER SELECT REGISTER 2
U-0 U-0 U-0 R/W-0 U-0 R/W-0 R/W-0 R/W-0
— — — C10TSEL0(1) — C9TSEL0(1) C8TSEL1 C8TSEL0
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7-5 Unimplemented: Read as ‘0’
bit 4 C10TSEL0: CCP10 Timer Selection bit(1)
0 = CCP10 is based off of TMR1/TMR2
1 = CCP10 is based off of TMR7/TMR2
bit 3 Unimplemented: Read as ‘0’
bit 2 C9TSEL0: CCP9 Timer Selection bit(1)
0 = CCP9 is based off of TMR1/TMR2
1 = CCP9 is based off of TMR7/TMR4
bit 1-0 C8TSEL<1:0>: CCP8 Timer Selection bits
On Non 32-Byte Device Variants:
00 = CCP8 is based off of TMR1/TMR2
01 = CCP8 is based off of TMR7/TMR4
10 = CCP8 is based off of TMR7/TMR6
11 = Reserved; do not use
On 32-Byte Device Variants (PIC18F65K22 and PIC18F85K22):
00 = CCP8 is based off of TMR1/TMR2
01 = CCP8 is based off of TMR1/TMR4
10 = CCP8 is based off of TMR1/TMR6
11 = Reserved; do not use
Note 1: Bit is unimplemented and reads as ‘0’ on the devices with 32 Kbytes of program memory (PIC18FX5K22).
PIC18F87K22 FAMILY
DS39960C-page 248 2011 Microchip Technology Inc.
REGISTER 19-4: CCPRxL: CCPx PERIOD LOW BYTE REGISTER
R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x
CCPRxL7 CCPRxL6 CCPRxL5 CCPRxL4 CCPRxL3 CCPRxL2 CCPRxL1 CCPRxL0
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7-0 CCPRxL<7:0>: CCPx Period Register Low Byte bits
Capture Mode: Capture Register Low Byte
Compare Mode: Compare Register Low Byte
PWM Mode: Duty Cycle Register
REGISTER 19-5: CCPRxH: CCPx PERIOD HIGH BYTE REGISTER
R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x
CCPRxH7 CCPRxH6 CCPRxH5 CCPRxH4 CCPRxH3 CCPRxH2 CCPRxH1 CCPRxH0
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7-0 CCPRxH<7:0>: CCPx Period Register High Byte bits
Capture Mode: Capture Register High Byte
Compare Mode: Compare Register High Byte
PWM Mode: Duty Cycle Buffer Register
2011 Microchip Technology Inc. DS39960C-page 249
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19.1 CCP Module Configuration
Each Capture/Compare/PWM module is associated
with a control register (generically, CCPxCON) and a
data register (CCPRx). The data register, in turn, is
comprised of two 8-bit registers: CCPRxL (low byte)
and CCPRxH (high byte). All registers are both
readable and writable.
19.1.1 CCP MODULES AND TIMER
RESOURCES
The CCP modules utilize Timers, 1 through 8, that vary
with the selected mode. Various timers are available to
the CCP modules in Capture, Compare or PWM
modes, as shown in Table 19-1.
TABLE 19-1: CCP MODE – TIMER
RESOURCE
The assignment of a particular timer to a module is
determined by the Timer to CCP enable bits in the
CCPTMRSx registers. (See Register 19-2 and
Register 19-3.) All of the modules may be active at
once and may share the same timer resource if they
are configured to operate in the same mode
(Capture/Compare or PWM) at the same time.
The CCPTMRS1 register selects the timers for CCP
modules, 7, 6, 5 and 4, and the CCPTMRS2 register
selects the timers for CCP modules, 10, 9 and 8. The
possible configurations are shown in Ta b l e 1 9 - 2 and
Table 19-3.
TABLE 19-2: TIMER ASSIGNMENTS FOR CCP MODULES 4, 5, 6 AND 7
TABLE 19-3: TIMER ASSIGNMENTS FOR CCP MODULES 8, 9 AND 10
CCP Mode Timer Resource
Capture
Timer1, Timer3, Timer 5 or Timer7
Compare
PWM Timer2, Timer4, Timer 6 or Timer8
CCPTMRS1 Register
CCP4 CCP5 CCP6 CCP7
C4TSEL
<1:0>
Capture/
Compare
Mode
PWM
Mode C5TSEL0 Capture/
Compare
Mode
PWM
Mode C6TSEL0 Capture/
Compare
Mode
PWM
Mode C7TSEL
<1:0>
Capture/
Compare
Mode
PWM
Mode
00 TMR1 TMR2 0TMR1 TMR2 0TMR1 TMR2 00 TMR1 TMR2
01 TMR3 TMR4 1TMR5 TMR4 1TMR5 TMR2 01 TMR5 TMR4
10 TMR3 TMR6 10 TMR5 TMR6
11 Reserved(1) 11 TMR5 TMR8
Note 1: Do not use the reserved bits.
CCPTMRS2 Register
CCP8 CCP8
Devices wi th 32 Kbyte s CCP9(1) CCP10(1)
C8TSEL
<1:0>
Capture/
Compare
Mode
PWM
Mode C8TSEL
<1:0>
Capture/
Compare
Mode
PWM
Mode C9TSEL0 Capture/
Compare
Mode
PWM
Mode C10TSEL0 Capture/
Compare
Mode
PWM
Mode
00 TMR1 TMR2 00 TMR1 TMR2 0TMR1 TMR2 0TMR1 TMR2
01 TMR7 TMR4 01 TMR1 TMR4 1TMR7 TMR4 1TMR7 TMR2
10 TMR7 TMR6 10 TMR1 TMR6
11 Reserved(2) 11 Reserved(2)
Note 1: Module is not available for devices with 32 Kbytes of program memory (PIC18F65K22 and PIC18F85K22).
2: Do not use the reserved setting.
PIC18F87K22 FAMILY
DS39960C-page 250 2011 Microchip Technology Inc.
19.1.2 OPEN-DRAIN OUTPUT OPTION
When operating in Output mode (the Compare or PWM
modes), the drivers for the CCPx pins can be optionally
configured as open-drain outputs. This feature allows
the voltage level on the pin to be pulled to a higher level
through an external pull-up resistor and allows the
output to communicate with external circuits without the
need for additional level shifters.
The open-drain output option is controlled by the
CCPxOD bits (ODCON2<7:0>). Setting the appropri-
ate bit configures the pin for the corresponding module
for open-drain operation.
19.1.3 PIN ASSIGNMENT FOR CCP6,
CCP7, CCP8 AND CCP9
The pin assignment for CCP6/7/8/9 (Capture input,
Compare and PWM output) can change, based on the
device configuration.
The ECCPMX Configuration bit (CONFIG3H<1>)
determines the pin to which CCP6/7/8/9 is multiplexed.
The pin assignments for these CCP modules are given
in Table 19-4.
TABLE 19-4: CCP PIN ASSIGNMENT
19.2 Capture Mode
In Capture mode, the CCPR4H:CCPR4L register pair
captures the 16-bit value of the Timer register selected
in the CCPTMRS1 when an event occurs on the CCP4
pin. An event is defined as one of the following:
• Every falling edge
• Every rising edge
• Every 4th rising edge
• Every 16th rising edge
The event is selected by the mode select bits,
CCP4M<3:0> (CCP4CON<3:0>). When a capture is
made, the interrupt request flag bit, CCP4IF (PIR4<1>),
is set. (It must be cleared in software.) If another
capture occurs before the value in CCPR4 is read, the
old captured value is overwritten by the new captured
value.
Figure 19-1 shows the Capture mode block diagram.
19.2.1 CCP PIN CONFIGURATION
In Capture mode, the appropriate CCPx pin should be
configured as an input by setting the corresponding
TRIS direction bit.
19.2.2 TIMER1/3/5/7 MODE SELECTION
For the available timers (1/3/5/7) to be used for the
capture feature, the used timers must be running in Timer
mode or Synchronized Counter mode. In Asynchronous
Counter mode, the capture operation may not work.
The timer to be used with each CCP module is selected
in the CCPTMRSx registers. (See Section 19.1.1 “C CP
Module s and Timer Re so ur c es” .)
Details of the timer assignments for the CCP modules
are given in Tab le 19 -2 and Table 19-3.
ECCPMX
Value
Pin Mapped To
CCP6 CCP7 CCP8 CC9
1
(Default) RE6 RE5 RE4 RE3
0RH7 RH6 RH5 RH4
Note: If RC1 or RE7 is configured as a CCP4
output, a write to the port causes a
capture condition.
2011 Microchip Technology Inc. DS39960C-page 251
PIC18F87K22 FAMILY
FIGURE 19-1: CAP TURE MODE OPERATION BLOCK DIAGRAM
19.2.3 SOFTWARE INTERRUPT
When the Capture mode is changed, a false capture
interrupt may be generated. The user should keep the
CCP4IE bit (PIE4<1>) clear to avoid false interrupts
and should clear the flag bit, CCP4IF, following any
such change in operating mode.
19.2.4 CCP PRESCALER
There are four prescaler settings in Capture mode.
They are specified as part of the operating mode
selected by the mode select bits (CCP4M<3:0>).
Whenever the CCP module is turned off, or the CCP
module is not in Capture mode, the prescaler counter
is cleared. This means that any Reset will clear the
prescaler counter.
Switching from one capture prescaler to another may
generate an interrupt. Doing that will also not clear the
prescaler counter – meaning the first capture may be
from a non-zero prescaler.
Example 19-1 shows the recommended method for
switching between capture prescalers. This example
also clears the prescaler counter and will not generate
the “false” interrupt.
EXAMPLE 19-1: CHANGING BETWEE N
CAPTURE PRESCALERS
CCPR5H CCPR5L
TMR1H TMR1L
Set CCP5IF
TMR5
Enable
Q1:Q4
CCP5CON<3:0>
CCP5 Pin
Prescaler
1, 4, 16
and
Edge Detect
TMR1
Enable
C5TSEL0
C5TSEL0
CCPR4H CCPR4L
TMR1H TMR1L
Set CCP4IF
TMR3
Enable
CCP4CON<3:0>
CCP4 Pin
Prescaler
1, 4, 16
TMR3H TMR3L
TMR1
Enable
C4TSEL0
C4TSEL1
C4TSEL0
C4TSEL1
TMR5H TMR5L
and
Edge Detect
4
4
4
Note: This block diagram uses CCP4 and CCP5, and their appropriate timers as an example. For details on all of
the CCP modules and their timer assignments, see Table 19-2 and Table 19-3.
CLRFCCP4CON ; Turn CCP module off
MOVLWNEW_CAPT_PS; Load WREG with the
; new prescaler mode
; value and CCP ON
MOVWFCCP4CON ; Load CCP4CON with
; this value
PIC18F87K22 FAMILY
DS39960C-page 252 2011 Microchip Technology Inc.
19.3 Compare Mode
In Compare mode, the 16-bit CCPR4 register value is
constantly compared against the Timer register pair
value selected in the CCPTMR1 register. When a
match occurs, the CCP4 pin can be:
• Driven high
•Driven low
• Toggled (high-to-low or low-to-high)
• Unchanged (that is, reflecting the state of the I/O
latch)
The action on the pin is based on the value of the mode
select bits (CCP4M<3:0>). At the same time, the
interrupt flag bit, CCP4IF, is set.
Figure 19-2 gives the Compare mode block diagram
19.3.1 CCP PIN CONFIGURATION
The user must configure the CCPx pin as an output by
clearing the appropriate TRIS bit.
19.3.2 TIMER1/3/5/7 MODE SELECTION
If the CCP module is using the compare feature in
conjunction with any of the Timer1/3/5/7 timers, the
timers must be running in Timer mode or Synchronized
Counter mode. In Asynchronous Counter mode, the
compare operation may not work.
19.3.3 SOFTWARE INTERRUPT MODE
When the Generate Software Interrupt mode is chosen
(CCP4M<3:0> = 1010), the CCP4 pin is not affected.
Only a CCP interrupt is generated, if enabled, and the
CCP4IE bit is set.
19.3.4 SPECIAL EVENT TRIGGER
Both CCP modules are equipped with a Special Event
Trigger. This is an internal hardware signal generated
in Compare mode to trigger actions by other modules.
The Special Event Trigger is enabled by selecting
the Compare Special Event Trigger mode
(CCP4M<3:0> = 1011).
For either CCP module, the Special Event Trigger resets
the Timer register pair for whichever timer resource is
currently assigned as the module’s time base. This
allows the CCPRx registers to serve as a programmable
period register for either timer.
The Special Event Trigger for CCP4 cannot start an
A/D conversion.
Note: Clearing the CCP4CON register will force
the RC1 or RE7 compare output latch
(depending on device configuration) to the
default low level. This is not the PORTC or
PORTE I/O data latch.
Note: Details of the timer assignments for the
CCP modules are given in Table 19-2 and
Ta b l e 1 9 - 3.
Note: The Special Event Trigger of ECCP2 can start
an A/D conversion, but the A/D Converter
must be enabled. For more information, see
Section 19.0 “Capture/Compare/PWM
(CCP) Modules”.
2011 Microchip Technology Inc. DS39960C-page 253
PIC18F87K22 FAMILY
FIGURE 19-2: COMPARE MODE OPERATION BLOCK DIAGRAM
TABLE 19-5: REGISTERS ASSOCIATED WITH CAPTURE, COMPARE, T IMER1/3/5/7
Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
INTCON GIE/GIEH PEIE/GIEL TMR0IE INT0IE RBIE TMR0IF INT0IF RBIF
RCON IPEN SBOREN CM RI TO PD POR BOR
PIR4 CCP10IF(1) CCP9IF(1) CCP8IF CCP7IF CCP6IF CCP5IF CCP4IF CCP3IF
PIE4 CCP10IE(1) CCP9IE(1) CCP8IE CCP7IE CCP6IE CCP5IE CCP4IE CCP3IE
IPR4 CCP10IP(1) CCP9IP(1) CCP8IP CCP7IP CCP6IP CCP5IP CCP4IP CCP3IP
TRISB TRISB7 TRISB6 TRISB5 TRISB4 TRISB3 TRISB2 TRISB1 TRISB0
TRISC TRISC7 TRISC6 TRISC5 TRISC4 TRISC3 TRISC2 TRISC1 TRISC0
TRISE TRISE7 TRISE6 TRISE5 TRISE4 TRISE3 TRISE2 TRISE1 TRISE0
TRISH(2) TRISH7 TRISH6 TRISH5 TRISH4 TRISH3 TRISH2 TRISH1 TRISH0
TMR1L Timer1 Register Low Byte
Legend: — = unimplemented, read as ‘0’. Shaded cells are not used by Capture/Compare or Timer1/3/5/7.
Note 1: Unimplemented on devices with a program memory of 32 Kbytes (PIC18F65K22 and PIC18F85K22).
2: Unimplemented on 64-pin devices (PIC18F6XK22), read as ‘0’.
CCPR5H CCPR5L
TMR1H TMR1L
Comparator QS
R
Output
Logic
Special Event Trigger
Set CCP5IF
CCP5 Pin
TRIS
CCP5CON<3:0>
Output Enable
TMR5H TMR5L 1
0
Compare
4
(Timer1/5 Reset)
Match
Note: This block diagram uses CCP4 and CCP5 and their appropriate timers as an example. For details on all of
the CCP modules and their timer assignments, see Table 19-2 and Table 19-3.
TMR1H TMR1L
TMR5H TMR5L
CCPR4H CCPR4L
Comparator
C4TSEL1
Set CCP4IF
1
0
QS
R
Output
Logic
Special Event Trigger
CCP4 Pin
TRIS
CCP4CON<3:0>
Output Enable
4
(Timer1/Timer3 Reset, A/D Trigger)
Compare
Match
C5TSEL0
C4TSEL0
PIC18F87K22 FAMILY
DS39960C-page 254 2011 Microchip Technology Inc.
TMR1H Timer1 Register High Byte
TMR3L Timer3 Register Low Byte
TMR3H Timer3 Register High Byte
TMR5L Timer5 Register Low Byte
TMR5H Timer5 Register High Byte
TMR7L(1) Timer7 Register Low Byte
TMR7H(1) Timer7 Register High Byte
T1CON TMR1CS1 TMR1CS0 T1CKPS1 T1CKPS0 SOSCEN T1SYNC RD16 TMR1ON
T3CON TMR3CS1 TMR3CS0 T3CKPS1 T3CKPS0 SOSCEN T3SYNC RD16 TMR3ON
T5CON TMR5CS1 TMR5CS0 T5CKPS1 T5CKPS0 SOSCEN T5SYNC RD16 TMR5ON
T7CON(1) TMR7CS1 TMR7CS0 T7CKPS1 T7CKPS0 SOSCEN T7SYNC RD16 TMR7ON
CCPR4L Capture/Compare/PWM Register 4 Low Byte
CCPR4H Capture/Compare/PWM Register 4 High Byte
CCPR5L Capture/Compare/PWM Register 5 Low Byte
CCPR5H Capture/Compare/PWM Register 5 High Byte
CCPR6L Capture/Compare/PWM Register 6 Low Byte
CCPR6H Capture/Compare/PWM Register 6 High Byte
CCPR7L Capture/Compare/PWM Register 7 Low Byte
CCPR7H Capture/Compare/PWM Register 7 High Byte
CCPR8L Capture/Compare/PWM Register 8 Low Byte
CCPR8H Capture/Compare/PWM Register 8 High Byte
CCPR9L(1) Capture/Compare/PWM Register 9 Low Byte
CCPR9H(1) Capture/Compare/PWM Register 9 High Byte
CCPR10L(1) Capture/Compare/PWM Register 10 Low Byte
CCPR10H(1) Capture/Compare/PWM Register 10 High Byte
CCP4CON —— DC4B1 DC4B0 CCP4M3 CCP4M2 CCP4M1 CCP4M0
CCP5CON —— DC5B1 DC5B0 CCP5M3 CCP5M2 CCP5M1 CCP5M0
CCP6CON —— DC6B1 DC6B0 CCP6M3 CCP6M2 CCP6M1 CCP6M0
CCP7CON —— DC7B1 DC7B0 CCP7M3 CCP7M2 CCP7M1 CCP7M0
CCP8CON —— DC8B1 DC8B0 CCP8M3 CCP8M2 CCP8M1 CCP8M0
CCP9CON(1) —— DC9B1 DC9B0 CCP9M3 CCP9M2 CCP9M1 CCP9M0
CCP10CON(1) —— DC10B1 DC10B0 CCP10M3 CCP10M2 CCP10M1 CCP10M0
CCPTMRS1 C7TSEL1 C7TSEL0 — C6TSEL0 — C5TSEL0 C4TSEL1 C4TSEL0
CCPTMRS2 — — —C10TSEL0
(1) — C9TSEL0(1) C8TSEL1 C8TSEL0
PMD3 CCP10MD(1) CCP9MD(1) CCP8MD CCP7MD CCP6MD CCP5MD CCP4MD TMR12MD(1)
TABLE 19-5: REGISTERS ASSOCIATED WITH CAP TURE, C OMPARE, TIME R1/3/5/7 (CONTIN UED)
Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
Legend: — = unimplemented, read as ‘0’. Shaded cells are not used by Capture/Compare or Timer1/3/5/7.
Note 1: Unimplemented on devices with a program memory of 32 Kbytes (PIC18F65K22 and PIC18F85K22).
2: Unimplemented on 64-pin devices (PIC18F6XK22), read as ‘0’.
2011 Microchip Technology Inc. DS39960C-page 255
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19.4 PWM Mode
In Pulse-Width Modulation (PWM) mode, the CCP4 pin
produces up to a 10-bit resolution PWM output. Since
the CCP4 pin is multiplexed with a PORTC or PORTE
data latch, the appropriate TRIS bit must be cleared to
make the CCP4 pin an output.
Figure 19-3 shows a simplified block diagram of the
ECCP1 module in PWM mode.
For a step-by-step procedure on how to set up the CCP
module for PWM operation, see Section 19.4.3
“Setup for PWM Operation”.
FIGURE 19-3: SIMPLIFIED PWM BLOCK
DIAGRAM
A PWM output (Figure 19-4) has a time base (period)
and a time that the output stays high (duty cycle). The
frequency of the PWM is the inverse of the period
(1/period).
FIGURE 19-4: PWM OUTPUT
19.4.1 PWM PERIOD
The PWM period is specified by writing to the PR2
register. The PWM period can be calculated using the
following formula:
EQUATION 19-1:
PWM frequency is defined as 1/[PWM period].
When TMR2 is equal to PR2, the following three events
occur on the next increment cycle:
•TMR2 is cleared
• The CCP4 pin is set
(An exception: If PWM duty cycle = 0%, the CCP4
pin will not be set)
• The PWM duty cycle is latched from CCPR4L into
CCPR4H
Note: Clearing the CCP4CON register will force
the RC1 or RE7 output latch (depending
on device configuration) to the default low
level. This is not the PORTC or PORTE
I/O data latch.
CCPR4L
CCPR4H (Slave)
Comparator
TMR2
Comparator
PR2
(Note 1)
RQ
S
Duty Cycle Registers CCP4CON<5:4>
Clear Timer,
ECCP1 Pin and
Latch D.C.
TRISC<2>
RC2/ECCP1
Note 1:The 8-bit TMR2 value is concatenated with the 2-bit
internal Q clock, or 2 bits of the prescaler, to create
the 10-bit time base.
2: CCP4 and its appropriate timers are used as an
example. For details on all of the CCP modules and
their timer assignments, see Ta b l e 1 9 - 2 and
Table 19-3.
Note: The Timer2 postscalers (see
Section 15.0 “Timer2 Module”) are not
used in the determination of the PWM fre-
quency. The postscaler could be used to
have a servo update rate at a different fre-
quency than the PWM output.
Period
Duty Cycle
TMR2 = PR2
TMR2 = Duty Cycle
TMR2 = PR2
PWM Period = [(PR2) + 1] • 4 • TOSC •
(TMR2 Prescale Value)
PIC18F87K22 FAMILY
DS39960C-page 256 2011 Microchip Technology Inc.
19.4.2 PWM DUTY CYCLE
The PWM duty cycle is specified, to use CCP4 as an
example, by writing to the CCPR4L register and to the
CCP4CON<5:4> bits. Up to 10-bit resolution is avail-
able. The CCPR4L contains the eight MSbs and the
CCP4CON<5:4> contains the two LSbs. This 10-bit
value is represented by CCPR4L:CCP4CON<5:4>.
The following equation is used to calculate the PWM
duty cycle in time:
EQUATION 19-2:
CCPR4L and CCP4CON<5:4> can be written to at any
time, but the duty cycle value is not latched into
CCPR4H until after a match between PR2 and TMR2
occurs (that is, the period is complete). In PWM mode,
CCPR4H is a read-only register.
The CCPR4H register and a two-bit internal latch are
used to double-buffer the PWM duty cycle. This
double-buffering is essential for glitchless PWM
operation.
When the CCPR4H and two-bit latch match TMR2,
concatenated with an internal two-bit Q clock or two
bits of the TMR2 prescaler, the CCP4 pin is cleared.
The maximum PWM resolution (bits) for a given PWM
frequency is given by the equation:
EQUATION 19-3:
TABLE 19-6: EXAMPLE PWM FREQUENCIES AND RESOLUTIONS AT 40 MHz
19.4.3 SETUP FOR PWM OPERATION
To configure the CCP module for PWM operation,
using CCP4 as an example:
1. Set the PWM period by writing to the PR2
register.
2. Set the PWM duty cycle by writing to the
CCPR4L register and CCP4CON<5:4> bits.
3. Make the CCP4 pin an output by clearing the
appropriate TRIS bit.
4. Set the TMR2 prescale value, then enable
Timer2 by writing to T2CON.
5. Configure the CCP4 module for PWM operation.
PWM Duty Cycle = (CCPR4L:CCP4CON<5:4>) •
TOSC • (TMR2 Prescale Value)
Note: If the PWM duty cycle value is longer than
the PWM period, the CCP4 pin will not be
cleared.
FOSC
FPWM
---------------
log
2log
----------------------------- b i t s=
PWM Resolution (max)
PWM Frequency 2.44 kHz 9.77 kHz 39.06 kHz 156.25 kHz 312.50 kHz 416.67 kHz
Timer Prescaler (1, 4, 16)1641111
PR2 Value FFh FFh FFh 3Fh 1Fh 17h
Maximum Resolution (bits) 10 10 10 8 7 6.58
TABLE 19-7: REGISTERS ASSOCIATED WITH PWM AND TIMERS
Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
INTCON GIE/GIEH PEIE/GIEL TMR0IE INT0IE RBIE TMR0IF INT0IF RBIF
RCON IPEN SBOREN CM RI TO PD POR BOR
PIR4 CCP10IF(1) CCP9IF(1) CCP8IF CCP7IF CCP6IF CCP5IF CCP4IF CCP3IF
PIE4 CCP10IE(1) CCP9IE(1) CCP8IE CCP7IE CCP6IE CCP5IE CCP4IE CCP3IE
IPR4 CCP10IP(1) CCP9IP(1) CCP8IP CCP7IP CCP6IP CCP5IP CCP4IP CCP3IP
TRISB TRISB7 TRISB6 TRISB5 TRISB4 TRISB3 TRISB2 TRISB1 TRISB0
TRISC TRISC7 TRISC6 TRISC5 TRISC4 TRISC3 TRISC2 TRISC1 TRISC0
TRISE TRISE7 TRISE6 TRISE5 TRISE4 TRISE3 TRISE2 TRISE1 TRISE0
Legend: — = unimplemented, read as ‘0’. Shaded cells are not used by PWM or Timer2/4/6/8.
Note 1: Unimplemented on devices with a program memory of 32 Kbytes (PIC18F65K22 and PIC18F85K22).
2: Unimplemented on 64-pin devices (PIC18F6XK22), read as ‘0’.
2011 Microchip Technology Inc. DS39960C-page 257
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TRISH(2) TRISH7 TRISH6 TRISH5 TRISH4 TRISH3 TRISH2 TRISH1 TRISH0
TMR2 Timer2 Register
TMR4 Timer4 Register
TMR6 Timer6 Register
TMR8 Timer8 Register
PR2 Timer2 Period Register
PR4 Timer4 Period Register
PR6 Timer6 Period Register
PR8 Timer8 Period Register
T2CON — T2OUTPS3 T2OUTPS2 T2OUTPS1 T2OUTPS0 TMR2ON T2CKPS1 T2CKPS0
T4CON — T4OUTPS3 T4OUTPS2 T4OUTPS1 T4OUTPS0 TMR4ON T4CKPS1 T4CKPS0
T6CON — T6OUTPS3 T6OUTPS2 T6OUTPS1 T6OUTPS0 TMR6ON T6CKPS1 T6CKPS0
T8CON — T8OUTPS3 T8OUTPS2 T8OUTPS1 T8OUTPS0 TMR8ON T8CKPS1 T8CKPS0
CCPR4L Capture/Compare/PWM Register 4 Low Byte
CCPR4H Capture/Compare/PWM Register 4 High Byte
CCPR5L Capture/Compare/PWM Register 5 Low Byte
CCPR5H Capture/Compare/PWM Register 5 High Byte
CCPR6L Capture/Compare/PWM Register 6 Low Byte
CCPR6H Capture/Compare/PWM Register 6 High Byte
CCPR7L Capture/Compare/PWM Register 7 Low Byte
CCPR7H Capture/Compare/PWM Register 7 High Byte
CCPR8L Capture/Compare/PWM Register 8 Low Byte
CCPR8H Capture/Compare/PWM Register 8 High Byte
CCPR9L(1) Capture/Compare/PWM Register 9 Low Byte
CCPR9H(1) Capture/Compare/PWM Register 9 High Byte
CCPR10L(1) Capture/Compare/PWM Register 10 Low Byte
CCPR10H(1) Capture/Compare/PWM Register 10 High Byte
CCP4CON —— DC4B1 DC4B0 CCP4M3 CCP4M2 CCP4M1 CCP4M0
CCP5CON —— DC5B1 DC5B0 CCP5M3 CCP5M2 CCP5M1 CCP5M0
CCP6CON —— DC6B1 DC6B0 CCP6M3 CCP6M2 CCP6M1 CCP6M0
CCP7CON —— DC7B1 DC7B0 CCP7M3 CCP7M2 CCP7M1 CCP7M0
CCP8CON —— DC8B1 DC8B0 CCP8M3 CCP8M2 CCP8M1 CCP8M0
CCP9CON(1) —— DC9B1 DC9B0 CCP9M3 CCP9M2 CCP9M1 CCP9M0
CCP10CON(1) —— DC10B1 DC10B0 CCP10M3 CCP10M2 CCP10M1 CCP10M0
CCPTMRS1 C7TSEL1 C7TSEL0 — C6TSEL0 — C5TSEL0 C4TSEL1 C4TSEL0
CCPTMRS2 — — — C10TSEL0(1) — C9TSEL0(1) C8TSEL1 C8TSEL0
PMD3 CCP10MD(1) CCP9MD(1) CCP8MD CCP7MD CCP6MD CCP5MD CCP4MD TMR12MD(1)
TABLE 19-7: REGISTERS ASSOCIATED WITH PWM AND TIMERS (CONTINUED)
Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
Legend: — = unimplemented, read as ‘0’. Shaded cells are not used by PWM or Timer2/4/6/8.
Note 1: Unimplemented on devices with a program memory of 32 Kbytes (PIC18F65K22 and PIC18F85K22).
2: Unimplemented on 64-pin devices (PIC18F6XK22), read as ‘0’.
PIC18F87K22 FAMILY
DS39960C-page 258 2011 Microchip Technology Inc.
NOTES:
2011 Microchip Technology Inc. DS39960C-page 259
PIC18F87K22 FAMILY
20.0 ENHANCED
CAPTURE/COMPARE/PWM
(ECCP) MODULE
PIC18F87K22 family devices have three Enhanced
Capture/Compare/PWM (ECCP) modules: ECCP1,
ECCP2 and ECCP3. These modules contain a 16-bit
register, which can operate as a 16-bit Capture register,
a 16-bit Compare register or a PWM Master/Slave Duty
Cycle register. These ECCP modules are upward
compatible with CCP
ECCP1, ECCP2 and ECCP3 are implemented as stan-
dard CCP modules with enhanced PWM capabilities.
These include:
• Provision for two or four output channels
• Output Steering modes
• Programmable polarity
• Programmable dead-band control
• Automatic shutdown and restart
The enhanced features are discussed in detail in
Section 20.4 “PWM (Enhanced Mode)”.
The ECCP1, ECCP2 and ECCP3 modules use the
control registers CCP1CON, CCP2CON and
CCP3CON. The control registers, CCP4CON through
CCP10CON, are for the modules, CCP4 through
CCP10.
Note: Throughout this section, generic references
are used for register and bit names that are
the same, except for an ‘x’ variable that indi-
cates the item’s association with the
ECCP1, ECCP2 or ECCP3 module. For
example, the control register is named
CCPxCON and refers to CCP1CON,
CCP2CON and CCP3CON.
PIC18F87K22 FAMILY
DS39960C-page 260 2011 Microchip Technology Inc.
REGISTER 20-1: CCPxCON: ENHANCED CAPTURE/COMPARE/PWM x CONTROL
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0
PxM1 PxM0 DCxB1 DCxB0 CCPxM3 CCPxM2 CCPxM1 CCPxM0
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7-6 PxM<1:0>: Enhanced PWM Output Configuration bits
If CCPxM<3:2> = 00, 01, 10:
xx = PxA assigned as capture/compare input/output; PxB, PxC and PxD assigned as port pins
If CCPxM<3:2> = 11:
00 = Single output: PxA, PxB, PxC and PxD are controlled by steering (see Section 20.4.7 “Pulse
Steering Mode”)
01 = Full-bridge output forward: PxD is modulated; PxA is active; PxB, PxC is inactive
10 = Half-bridge output: PxA, PxB are modulated with dead-band control; PxC and PxD are
assigned as port pins
11 = Full-bridge output reverse: PxB is modulated; PxC is active; PxA and PxD are inactive
bit 5-4 DCxB<1:0>: PWM Duty Cycle bit 1 and bit 0
Capture mode:
Unused.
Compare mode:
Unused.
PWM mode:
These bits are the two LSbs of the 10-bit PWM duty cycle. The eight MSbs of the duty cycle are found
in CCPRxL.
bit 3-0 CCPxM<3:0>: ECCPx Mode Select bits
0000 = Capture/Compare/PWM off (resets ECCPx module)
0001 = Reserved
0010 = Compare mode: toggle output on match
0011 = Capture mode
0100 = Capture mode: every falling edge
0101 = Capture mode: every rising edge
0110 = Capture mode: every fourth rising edge
0111 = Capture mode: every 16th rising edge
1000 = Compare mode: initialize ECCPx pin low, set output on compare match (set CCPxIF)
1001 = Compare mode: initialize ECCPx pin high, clear output on compare match (set CCPxIF)
1010 = Compare mode: generate software interrupt only, ECCPx pin reverts to I/O state
1011 = Compare mode: trigger special event (ECCPx resets TMR1 or TMR3, starts A/D conversion,
sets CCPxIF bit)
1100 = PWM mode: PxA and PxC are active-high; PxB and PxD are active-high
1101 = PWM mode: PxA and PxC are active-high; PxB and PxD are active-low
1110 = PWM mode: PxA and PxC are active-low; PxB and PxD are active-high
1111 = PWM mode: PxA and PxC are active-low; PxB and PxD are active-low
2011 Microchip Technology Inc. DS39960C-page 261
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REGISTER 20-2: CCPTMRS0: CCP TIMER SELECT 0 REGISTER
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0
C3TSEL1 C3TSEL0 C2TSEL2 C2TSEL1 C2TSEL0 C1TSEL2 C1TSEL1 C1TSEL0
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7-6 C3TSEL<1:0>: ECCP3 Timer Selection bit
00 = ECCP3 is based off of TMR1/TMR2
01 = ECCP3 is based off of TMR3/TMR4
10 = ECCP3 is based off of TMR3/TMR6
11 = ECCP3 is based off of TMR3/TMR8
bit 5-3 C2TSEL<2:0>: ECCP2 Timer Selection bit
000 = ECCP2 is based off of TMR1/TMR2
001 = ECCP2 is based off of TMR3/TMR4
010 = ECCP2 is based off of TMR3/TMR6
011 = ECCP2 is based off of TMR3/TMR8
100 = ECCP2 is based off of TMR3/TMR10: option reserved on the 32-Kbyte device variant; do not use
101 = Reserved; do not use
110 = Reserved; do not use
111 = Reserved; do not use
bit 2-0 C1TSEL<2:0>: ECCP1 Timer Selection bit
000 = ECCP1 is based off of TMR1/TMR2
001 = ECCP1 is based off of TMR3/TMR4
010 = ECCP1 is based off of TMR3/TMR6
011 = ECCP1 is based off of TMR3/TMR8
100 = ECCP1 is based off of TMR3/TMR10: option reserved on the 32-Kbyte device variant; do not use
101 = ECCP1 is based off of TMR3/TMR12: option reserved on the 32-Kbyte device variant; do not use
110 = Reserved; do not use
111 = Reserved; do not use
PIC18F87K22 FAMILY
DS39960C-page 262 2011 Microchip Technology Inc.
In addition to the expanded range of modes available
through the CCPxCON and ECCPxAS registers, the
ECCP modules have two additional registers associated
with Enhanced PWM operation and auto-shutdown
features. They are:
• ECCPxDEL – Enhanced PWM Control
• PSTRxCON – Pulse Steering Control
20.1 ECCP Outputs and Configuration
The Enhanced CCP module may have up to four PWM
outputs, depending on the selected operating mode.
The CCPxCON register is modified to allow control
over four PWM outputs: ECCPx/PxA, PxB, PxC and
PxD. Applications can use one, two or four of these
outputs.
The outputs that are active depend on the ECCP
operating mode selected. The pin assignments are
summarized in Table 20-3.
To configure the I/O pins as PWM outputs, the proper
PWM mode must be selected by setting the PxM<1:0>
and CCPxM<3:0> bits. The appropriate TRIS direction
bits for the port pins must also be set as outputs.
20.1.1 ECCP MODULE AND TIMER
RESOURCES
The ECCP modules use Timers, 1, 2, 3, 4, 6, 8, 10 or 12,
depending on the mode selected. These timers are
available to CCP modules in Capture, Compare or PWM
modes, as shown in Table 20-1.
TABLE 20-1: ECCP MODE – TIMER
RESOURCE
The assignment of a particular timer to a module is
determined by the Timer to ECCP enable bits in the
CCPTMRSx register (Register 20-2). The interactions
between the two modules are depicted in Figure 20-1.
Capture operations are designed to be used when the
timer is configured for Synchronous Counter mode.
Capture operations may not work as expected if the
associated timer is configured for Asynchronous Counter
mode.
20.1.2 ECCP PIN ASSIGNMENT
The pin assignment for ECCPx (Capture input, Com-
pare and PWM output) can change, based on device
configuration. The ECCPMX (CONFIG3H<1>) Config-
uration bit determines to which pin ECCP1 and ECCP3
are multiplexed.
• Default/ECCPMX = 1:
- ECCP1 (P1B/P1C) multiplexed onto RE6 and
RE5
- ECCP3 (P3B/P3C) multiplexed onto RE4 and
RE3
• ECCPMX = 0:
- ECCP1 (P1B/P1C) multiplexed onto RH7
and RH6
- ECCP3 (P3B/P3C) multiplexed onto RH5
and RH4.
The pin assignment for ECCP2 (Capture input,
Compare and PWM output) can change, based on the
device configuration.
The CCP2MX Configuration bit (CONFIG3H<0>)
determines to which pin ECCP2 is multiplexed.
• If CCP2MX = 1 (default) – ECCP2 is multiplexed
to RC1
• If CCP2MX = 0 – ECCP2 is multiplexed to RE7
ECCP Mode Timer Resource
Capture Timer1 or Timer3
Compare Timer1 or Timer3
PWM Timer2, Timer4, Timer6, Timer8,
Timer10 or Timer12
2011 Microchip Technology Inc. DS39960C-page 263
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20.2 Capture Mode
In Capture mode, the CCPRxH:CCPRxL register pair
captures the 16-bit value of the TMR1 or TMR3
registers when an event occurs on the corresponding
ECCPx pin. An event is defined as one of the following:
• Every falling edge
• Every rising edge
• Every fourth rising edge
•Every 16
th rising edge
The event is selected by the mode select bits,
CCPxM<3:0> (CCPxCON<3:0>). When a capture is
made, the interrupt request flag bit, CCPxIF, is set (see
Table 20-2). The flag must be cleared by software. If
another capture occurs before the value in the
CCPRxH/L register is read, the old captured value is
overwritten by the new captured value.
20.2.1 ECCP PIN CONFIGURATION
In Capture mode, the appropriate ECCPx pin should be
configured as an input by setting the corresponding
TRIS direction bit.
20.2.2 TIMER1/2/3/4/6/8/10/12 MODE
SELECTION
The timers that are to be used with the capture feature
(Timer1 2, 3, 4, 6, 8, 10 or 12) must be running in Timer
mode or Synchronized Counter mode. In Asynchro-
nous Counter mode, the capture operation may not
work. The timer to be used with each ECCP module is
selected in the CCPTMRS0 register (Register 20-2).
20.2.3 SOFTWARE INTERRUPT
When the Capture mode is changed, a false capture
interrupt may be generated. The user should keep the
CCPxIE interrupt enable bit clear to avoid false interrupts.
The interrupt flag bit, CCPxIF, should also be cleared
following any such change in operating mode.
20.2.4 ECCP PRESCALER
There are four prescaler settings in Capture mode; they
are specified as part of the operating mode selected by
the mode select bits (CCPxM<3:0>). Whenever the
ECCP module is turned off, or Capture mode is dis-
abled, the prescaler counter is cleared. This means
that any Reset will clear the prescaler counter.
Switching from one capture prescaler to another may
generate an interrupt. Also, the prescaler counter will
not be cleared; therefore, the first capture may be from
a non-zero prescaler. Example 20-1 provides the
recommended method for switching between capture
prescalers. This example also clears the prescaler
counter and will not generate the “false” interrupt.
EXAMPLE 20-1: CHANGING BETWEE N
CAPTURE PRESCALERS
FIGURE 20-1: CAP TURE MODE OPERATION BLOCK DIAGRAM
TABLE 20-2: ECCP1/2/3 INTERRUPT FLAG
BITS
ECCP Module Flag Bit
1 PIR3<1>
2 PIR3<2>
3 PIR4<0>
Note: If the ECCPx pin is configured as an out-
put, a write to the port can cause a capture
condition.
CLRF CCP1CON ; Turn ECCP module off
MOVLW NEW_CAPT_PS ; Load WREG with the
; new prescaler mode
; value and ECCP ON
MOVWF CCP1CON ; Load CCP1CON with
; this value
CCPR1H CCPR1L
TMR1H TMR1L
Set CCP1IF
TMR3
Enable
Q1:Q4
CCP1CON<3:0>
ECCP1 Pin
Prescaler
1, 4, 16
and
Edge Detect
TMR1
Enable
C1TSEL0
TMR3H TMR3L
4
4
C1TSEL1
C1TSEL2
C1TSEL0
C1TSEL1
C1TSEL2
PIC18F87K22 FAMILY
DS39960C-page 264 2011 Microchip Technology Inc.
20.3 Compare Mode
In Compare mode, the 16-bit CCPRx register value is
constantly compared against the Timer register pair
value selected in the CCPTMR1 register. When a
match occurs, the ECCPx pin can be:
• Driven high
•Driven low
• Toggled (high-to-low or low-to-high)
• Unchanged (that is, reflecting the state of the I/O
latch)
The action on the pin is based on the value of the mode
select bits (CCPxM<3:0>). At the same time, the
interrupt flag bit, CCPxIF, is set.
20.3.1 ECCP PIN CONFIGURATION
Users must configure the ECCPx pin as an output by
clearing the appropriate TRIS bit.
20.3.2 TIMER1/2/3/4/6/8/10/12 MODE
SELECTION
Timer1 2, 3, 4, 6, 8, 10 or 12 must be running in Timer
mode or Synchronized Counter mode if the ECCP
module is using the compare feature. In Asynchronous
Counter mode, the compare operation will not work
reliably.
20.3.3 SOFTWARE INTERRUPT MODE
When the Generate Software Interrupt mode is chosen
(CCPxM<3:0> = 1010), the ECCPx pin is not affected;
only the CCPxIF interrupt flag is affected.
20.3.4 SPECIAL EVENT TRIGGER
The ECCP module is equipped with a Special Event
Trigger. This is an internal hardware signal generated
in Compare mode to trigger actions by other modules.
The Special Event Trigger is enabled by selecting
the Compare Special Event Trigger mode
(CCPxM<3:0> = 1011).
The Special Event Trigger resets the Timer register pair
for whichever timer resource is currently assigned as the
module’s time base. This allows the CCPRx registers to
serve as a programmable period register for either timer.
The Special Event Trigger can also start an A/D conver-
sion. In order to do this, the A/D Converter must
already be enabled.
FIGURE 20-2: COMPARE MODE OPERATION BLOCK DIAGRAM
Note: Clearing the CCPxCON register will force
the ECCPx compare output latch
(depending on device configuration) to the
default low level. This is not the PORTx
I/O data latch.
TMR1H TMR1L
TMR3H TMR3L
CCPR1H CCPR1L
Comparator
Set CCP1IF
1
0
Q
S
R
Output
Logic
ECCP1 Pin
TRIS
CCP1CON<3:0>
Output Enable
4
(Timer1/Timer3 Reset, A/D Trigger)
Compare
Match
C1TSEL0
C1TSEL1
C1TSEL2
Special Event Trigger
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20.4 PWM (Enhanced Mode)
The Enhanced PWM mode can generate a PWM signal
on up to four different output pins with up to 10 bits of
resolution. It can do this through four different PWM
Output modes:
• Single PWM
• Half-Bridge PWM
• Full-Bridge PWM, Forward mode
• Full-Bridge PWM, Reverse mode
To select an Enhanced PWM mode, the PxM bits of the
CCPxCON register must be set appropriately.
The PWM outputs are multiplexed with I/O pins and are
designated: PxA, PxB, PxC and PxD. The polarity of the
PWM pins is configurable and is selected by setting the
CCPxM bits in the CCPxCON register appropriately.
Table 20-1 provides the pin assignments for each
Enhanced PWM mode.
Figure 20-3 provides an example of a simplified block
diagram of the Enhanced PWM module.
FIGURE 20- 3: EXAMPLE SIMPLIFI ED B LOCK DIA GRAM O F T HE E NHANC ED P WM MODE
Note: To prevent the generation of an
incomplete waveform when the PWM is
first enabled, the ECCP module waits until
the start of a new PWM period before
generating a PWM signal.
Note 1: The TRIS register value for each PWM output must be configured appropriately.
2: Any pin not used by an Enhanced PWM mode is available for alternate pin functions.
CCPR1L
CCPR1H (Slave)
Comparator
TMR2
Comparator
PR2
(1)
RQ
S
Duty Cycle Registers DC1B<1:0>
Clear Timer2,
Toggle PWM Pin and
Latch Duty Cycle
Note 1: The 8-bit TMR2 register is concatenated with the 2-bit internal Q clock, or 2 bits of the prescaler to create
the 10-bit time base.
TRIS
ECCP1/Output Pi
n
TRIS
Output Pi
n
TRIS
Output Pi
n
TRIS
Output Pi
n
Output
Controller
PxM<1:0>
2
CCPxM<3:0>
4
ECCP1DEL
ECCPx/PxA
PxB
PxC
PxD
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TABLE 20-3: EXAMPLE PIN ASSIGNMENTS FOR VARIOUS PWM ENHANCED MODES
FIGURE 20-4: EXAMPLE PWM (ENHANCED MODE) OUTPUT RELATIONSHIPS
(ACTIVE-HIGH STATE)
ECCP Mode PxM<1:0> PxA PxB PxC PxD
Single 00 Yes(1) Yes(1) Yes (1) Yes(1)
Half-Bridge 10 Yes Yes No No
Full-Bridge, Forward 01 Yes Yes Yes Yes
Full-Bridge, Reverse 11 Yes Ye s Yes Yes
Note 1: Outputs are enabled by pulse steering in Single mode (see Register 20-5).
0
Period
00
10
01
11
Signal PR2 + 1
PxM<1:0>
PxA Modulated
PxA Modulated
PxB Modulated
PxA Active
PxB Inactive
PxC Inactive
PxD Modulated
PxA Inactive
PxB Modulated
PxC Active
PxD Inactive
Pulse Width
(Single Output)
(Half-Bridge)
(Full-Bridge,
Forward)
(Full-Bridge,
Reverse)
Delay(1) Delay(1)
Relationships:
• Period = 4 * T
OSC * (PR2 + 1) * (TMR2 Prescale Value)
• Pulse Width = TOSC * (CCPRxL<7:0>:CCPxCON<5:4>) * (TMR2 Prescale Value)
• Delay = 4 * TOSC * (ECCPxDEL<6:0>)
Note 1: Dead-band delay is programmed using the ECCPxDEL register (Sec tio n 20. 4.6 “ P r ogr am m ab le Dea d- Ban d
Delay Mode”).
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FIGURE 20-5: EX AMP LE ENHA NCED PWM OUTPUT RELATIONSHIPS (ACTIVE-LOW STATE)
0
Period
00
10
01
11
Signal PR2 + 1
PxM<1:0>
PxA Modulated
PxA Modulated
PxB Modulated
PxA Active
PxB Inactive
PxC Inactive
PxD Modulated
PxA Inactive
PxB Modulated
PxC Active
PxD Inactive
Pulse
Width
(Single Output)
(Half-Bridge)
(Full-Bridge,
Forward)
(Full-Bridge,
Reverse)
Delay(1) Delay(1)
Relationships:
• Period = 4 * T
OSC * (PR2 + 1) * (TMR2 Prescale Value)
• Pulse Width = TOSC * (CCPRxL<7:0>:CCPxCON<5:4>) * (TMR2 Prescale Value)
• Delay = 4 * TOSC * (ECCPxDEL<6:0>)
Note 1: Dead-band delay is programmed using the ECCP1DEL register (Section 20.4.6 “Programmable Dead-Band
Delay Mode”).
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20.4.1 HALF-BRIDGE MODE
In Half-Bridge mode, two pins are used as outputs to
drive push-pull loads. The PWM output signal is output
on the PxA pin, while the complementary PWM output
signal is output on the PxB pin (see Figure 20-6). This
mode can be used for half-bridge applications, as
shown in Figure 20-7, or for full-bridge applications,
where four power switches are being modulated with
two PWM signals.
In Half-Bridge mode, the programmable dead-band delay
can be used to prevent shoot-through current in
half-bridge power devices. The value of the PxDC<6:0>
bits of the ECCPxDEL register sets the number of
instruction cycles before the output is driven active. If the
value is greater than the duty cycle, the corresponding
output remains inactive during the entire cycle. For more
details on the dead-band delay operations, see
Section 20.4.6 “Programmable Dead-Band Delay
Mode”.
Since the PxA and PxB outputs are multiplexed with the
PORT data latches, the associated TRIS bits must be
cleared to configure PxA and PxB as outputs.
FIGURE 20-6: EXAMPLE OF
HALF-BRIDGE PWM
OUTPUT
FIGURE 20-7: EX AMP L E OF HALF-BRIDGE APPLICATIONS
Period
Pulse Width
td
td
(1)
PxA(2)
PxB(2)
td = Dead-Band Delay
Period
(1) (1)
Note 1: At this time, the TMR2 register is equal to the
PR2 register.
2: Output signals are shown as active-high.
PxA
PxB
FET
Driver
FET
Driver
Load
+
-
+
-
FET
Driver
FET
Driver
V+
Load
FET
Driver
FET
Driver
PxA
PxB
Standard Half-Bridge Circuit (“Push-Pull”)
Half-Bridge Output Driving a Full-Bridge Circuit
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20.4.2 FULL-BRIDGE MODE
In Full-Bridge mode, all four pins are used as outputs.
An example of a full-bridge application is provided in
Figure 20-8.
In the Forward mode, the PxA pin is driven to its active
state and the PxD pin is modulated, while the PxB and
PxC pins are driven to their inactive state, as provided in
Figure 20-9.
In the Reverse mode, the PxC pin is driven to its active
state and the PxB pin is modulated, while the PxA and
PxD pins are driven to their inactive state, as provided
Figure 20-9.
The PxA, PxB, PxC and PxD outputs are multiplexed
with the port data latches. The associated TRIS bits
must be cleared to configure the PxA, PxB, PxC and
PxD pins as outputs.
FIGURE 20-8: EX AMP LE OF FULL-BRIDGE APPLICA TION
PxA
PxC
FET
Driver
FET
Driver
V+
V-
Load
FET
Driver
FET
Driver
PxB
PxD
QA
QB QD
QC
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FIGURE 20-9: EXAMPLE OF FULL-BRIDGE PWM OUTPUT
Period
Pulse Width
PxA(2)
PxB(2)
PxC(2)
PxD(2)
Forw a r d M o de
(1)
Period
Pulse Width
PxA(2)
PxC(2)
PxD(2)
PxB(2)
Reverse Mode
(1)
(1)
(1)
Note 1: At this time, the TMR2 register is equal to the PR2 register.
2: The output signal is shown as active-high.
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20.4.2.1 Direction Change in Full-Bridge
Mode
In Full-Bridge mode, the PxM1 bit in the CCPxCON
register allows users to control the forward/reverse
direction. When the application firmware changes this
direction control bit, the module will change to the new
direction on the next PWM cycle.
A direction change is initiated in software by changing
the PxM1 bit of the CCPxCON register. The following
sequence occurs prior to the end of the current PWM
period:
• The modulated outputs (PxB and PxD) are placed
in their inactive state.
• The associated unmodulated outputs (PxA and
PxC) are switched to drive in the opposite
direction.
• PWM modulation resumes at the beginning of the
next period.
For an illustration of this sequence, see Figure 20-10.
The Full-Bridge mode does not provide a dead-band
delay. As one output is modulated at a time, a
dead-band delay is generally not required. There is a
situation where a dead-band delay is required. This
situation occurs when both of the following conditions
are true:
• The direction of the PWM output changes when
the duty cycle of the output is at or near 100%.
• The turn-off time of the power switch, including
the power device and driver circuit, is greater than
the turn-on time.
Figure 20-11 shows an example of the PWM direction
changing from forward to reverse, at a near 100% duty
cycle. In this example, at time, t1, the PxA and PxD
outputs become inactive, while the PxC output
becomes active. Since the turn-off time of the power
devices is longer than the turn-on time, a shoot-through
current will flow through power devices, QC and QD
(see Figure 20-8), for the duration of ‘t’. The same
phenomenon will occur to power devices, QA and QB,
for PWM direction change from reverse to forward.
If changing PWM direction at high duty cycle is required
for an application, two possible solutions for eliminating
the shoot-through current are:
• Reduce PWM duty cycle for one PWM period
before changing directions.
• Use switch drivers that can drive the switches off
faster than they can drive them on.
Other options to prevent shoot-through current may
exist.
FIGURE 20-10: EXAMP LE OF PWM DIRECTION CHANGE
Pulse Width
Period(1)
Signal
Note 1: The direction bit, PxM1 of the CCPxCON register, is written any time during the PWM cycle.
2: When changing directions, the PxA and PxC signals switch before the end of the current PWM cycle. The
modulated PxB and PxD signals are inactive at this time. The length of this time is:
(1/FOSC) • TMR2 Prescale Value.
Period
(2)
PxA (Active-High)
PxB (Active-High)
PxC (Active-High)
PxD (Active-High)
Pulse Width
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FIGURE 20-11: EX AMPLE OF PW M DIRECTION CHANGE AT NEAR 100% DUTY CYCLE
20.4.3 START-UP CONSIDERATIONS
When any PWM mode is used, the application
hardware must use the proper external pull-up and/or
pull-down resistors on the PWM output pins.
The CCPxM<1:0> bits of the CCPxCON register allow
the user to choose whether the PWM output signals are
active-high or active-low for each pair of PWM output
pins (PxA/PxC and PxB/PxD). The PWM output
polarities must be selected before the PWM pin output
drivers are enabled. Changing the polarity configura-
tion while the PWM pin output drivers are enabled is
not recommended since it may result in damage to the
application circuits.
The PxA, PxB, PxC and PxD output latches may not be
in the proper states when the PWM module is
initialized. Enabling the PWM pin output drivers at the
same time as the Enhanced PWM modes may cause
damage to the application circuit. The Enhanced PWM
modes must be enabled in the proper Output mode and
complete a full PWM cycle before enabling the PWM
pin output drivers. The completion of a full PWM cycle
is indicated by the TMR2IF or TMR4IF bit of the PIR1
or PIR5 register being set as the second PWM period
begins.
20.4.4 ENHANCED PWM
AUTO-SHUTDOWN MODE
The PWM mode supports an Auto-Shutdown mode that
will disable the PWM outputs when an external
shutdown event occurs. Auto-Shutdown mode places
the PWM output pins into a predetermined state. This
mode is used to help prevent the PWM from damaging
the application.
The auto-shutdown sources are selected using the
ECCPxAS<2:0> bits (ECCPxAS<6:4>). A shutdown
event may be generated by:
• A logic ‘0’ on the pin that is assigned the FLT0
input function
• Comparator C1
• Comparator C2
• Setting the ECCPxASE bit in firmware
A shutdown condition is indicated by the ECCPxASE
(Auto-Shutdown Event Status) bit (ECCPxAS<7>). If
the bit is a ‘0’, the PWM pins are operating normally. If
the bit is a ‘1’, the PWM outputs are in the shutdown
state.
Forward Period Reverse Period
PxA
TON
TOFF
T = TOFF – TON
PxB
PxC
PxD
External Switch D
Potential
Shoot-Through Current
Note 1: All signals are shown as active-high.
2: TON is the turn-on delay of power switch QC and its driver.
3: TOFF is the turn-off delay of power switch QD and its driver.
External Switch C
t1
PW
PW
Note: When the microcontroller is released from
Reset, all of the I/O pins are in the
high-impedance state. The external
circuits must keep the power switch
devices in the OFF state until the micro-
controller drives the I/O pins with the
proper signal levels or activates the PWM
output(s).
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When a shutdown event occurs, two things happen:
• The ECCPxASE bit is set to ‘1’. The ECCPxASE
will remain set until cleared in firmware or an
auto-restart occurs. (See Section 20.4.5
“Auto-Restart Mode”.)
• The enabled PWM pins are asynchronously
placed in their shutdown states. The PWM output
pins are grouped into pairs (PxA/PxC) and
(PxB/PxD). The state of each pin pair is
determined by the PSSxAC and PSSxBD bits
(ECCPxAS<3:2> and <1:0>, respectively).
Each pin pair may be placed into one of three states:
• Drive logic ‘1’
• Drive logic ‘0’
• Tri-state (high-impedance)
REGISTER 20-3: ECCPxAS: ECCPx AUTO-SHUTDOWN CONTROL REGISTER
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0
ECCPxASE ECCPxAS2 ECCPxAS1 ECCPxAS0 PSSxAC1 PSSxAC0 PSSxBD1 PSSxBD0
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 ECCPxASE: ECCP Auto-Shutdown Event Status bit
1 = A shutdown event has occurred; ECCP outputs are in a shutdown state
0 = ECCP outputs are operating
bit 6-4 ECCPxAS<2:0>: ECCP Auto-Shutdown Source Select bits
000 = Auto-shutdown is disabled
001 = Comparator C1OUT output is high
010 = Comparator C2OUT output is high
011 = Either Comparator C1OUT or C2OUT is high
100 =V
IL on FLT0 pin
101 =V
IL on FLT0 pin or Comparator C1OUT output is high
110 =V
IL on FLT0 pin or Comparator C2OUT output is high
111 =V
IL on FLT0 pin or Comparator C1OUT or Comparator C2OUT is high
bit 3-2 PSSxAC<1:0>: PxA and PxC Pins Shutdown State Control bits
00 = Drive pins, PxA and PxC, to ‘0’
01 = Drive pins, PxA and PxC, to ‘1’
1x = PxA and PxC pins tri-state
bit 1-0 PSSxBD<1:0>: Pins PxB and PxD Shutdown State Control bits
00 = Drive pins, PxB and PxD, to ‘0’
01 = Drive pins, PxB and PxD, to ‘1’
1x = PxB and PxD pins tri-state
Note 1: The auto-shutdown condition is a level-based signal, not an edge-based signal. As long as the level is
present, the auto-shutdown will persist.
2: Writing to the ECCPxASE bit is disabled while an auto-shutdown condition persists.
3: Once the auto-shutdown condition has been removed and the PWM restarted (either through firmware or
auto-restart), the PWM signal will always restart at the beginning of the next PWM period.
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FIGURE 20-12: PWM AUTO-SHUTDOWN WITH FIRMWARE RESTART (PxRSEN = 0)
20.4.5 AUTO-RESTART MODE
The Enhanced PWM can be configured to automatically
restart the PWM signal once the auto-shutdown condi-
tion has been removed. Auto-restart is enabled by
setting the PxRSEN bit (ECCPxDEL<7>).
If auto-restart is enabled, the ECCPxASE bit will
remain set as long as the auto-shutdown condition is
active. When the auto-shutdown condition is removed,
the ECCPxASE bit will be cleared via hardware and
normal operation will resume.
The module will wait until the next PWM period begins,
however, before re-enabling the output pin. This behav-
ior allows the auto-shutdown with auto-restart features
to be used in applications based on current mode of
PWM control.
FIGURE 20-13: PWM AUTO-SHUTDOWN WITH AUTO-REST ART ENABLED (PxRSEN = 1)
Shutdown
PWM
ECCPxASE bit
Activity
Event
Shutdown
Event Occurs
Shutdown
Event Clears
PWM
Resumes
Normal PWM
Start of
PWM Period
ECCPxASE
Cleared by
Firmware
PWM Period
Shutdown
PWM
ECCPxASE bit
Activity
Event
Shutdown
Event Occurs
Shutdown
Event Clears
PWM
Resumes
Normal PWM
Start of
PWM Period
PWM Period
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20.4.6 PROGRAMMABLE DEAD-BAND
DELAY MODE
In half-bridge applications, where all power switches are
modulated at the PWM frequency, the power switches
normally require more time to turn off than to turn on. If
both the upper and lower power switches are switched
at the same time (one turned on and the other turned
off), both switches may be on for a short period until one
switch completely turns off. During this brief interval, a
very high current (shoot-through current) will flow
through both power switches, shorting the bridge supply.
To avoid this potentially destructive shoot-through
current from flowing during switching, turning on either of
the power switches is normally delayed to allow the
other switch to completely turn off.
In Half-Bridge mode, a digitally programmable
dead-band delay is available to avoid shoot-through
current from destroying the bridge power switches. The
delay occurs at the signal transition from the non-active
state to the active state. For an illustration, see
Figure 20-14. The lower seven bits of the associated
ECCPxDEL register (Register 20-4) set the delay
period in terms of microcontroller instruction cycles
(T
CY or 4 TOSC).
FIGURE 20-14: EXAMPLE OF
HALF-BRIDGE PWM
OUTPUT
FIGURE 20-15 : EXAMPL E OF HALF-BRIDGE APPLICATIONS
Period
Pulse Width
td
td
(1)
PxA(2)
PxB(2)
td = Dead-Band Delay
Period
(1) (1)
Note 1: At this time, the TMR2 register is equal to the
PR2 register.
2: Output signals are shown as active-high.
PxA
PxB
FET
Driver
FET
Driver
V+
V-
Load
+
V
-
+
V
-
Standard Half-Bridge Circuit (“Push-P ull ”)
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20.4.7 PULSE STEERING MODE
In Single Output mode, pulse steering allows any of the
PWM pins to be the modulated signal. Additionally, the
same PWM signal can simultaneously be available on
multiple pins.
Once the Single Output mode is selected
(CCPxM<3:2> = 11 and PxM<1:0> = 00 of the
CCPxCON register), the user firmware can bring out
the same PWM signal to one, two, three or four output
pins by setting the appropriate STR<D:A> bits
(PSTRxCON<3:0>), as provided in Table 20-3.
While the PWM Steering mode is active, the
CCPxM<1:0> bits (CCPxCON<1:0>) select the PWM
output polarity for the Px<D:A> pins.
The PWM auto-shutdown operation also applies to the
PWM Steering mode, as described in Section 20.4.4
“Enhanced PWM Auto-shutdown mode”. An
auto-shutdown event will only affect pins that have
PWM outputs enabled.
REGISTER 20-4: ECCPxDEL: ENHANCED PWM CONTROL REGISTER
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0
PxRSEN PxDC6 PxDC5 PxDC4 PxDC3 PxDC2 PxDC1 PxDC0
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 PxRSEN: PWM Restart Enable bit
1 = Upon auto-shutdown, the ECCPxASE bit clears automatically once the shutdown event goes
away; the PWM restarts automatically
0 = Upon auto-shutdown, ECCPxASE must be cleared by software to restart the PWM
bit 6-0 PxDC<6:0>: PWM Delay Count bits
PxDCn = Number of FOSC/4 (4 * TOSC) cycles between the scheduled time when a PWM signal
should transition active and the actual time it does transition active.
Note: The associated TRIS bits must be set to
output (‘0’) to enable the pin output driver
in order to see the PWM signal on the pin.
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REGISTER 20-5: PSTRxCON: PULSE STEERING CONTROL(1)
R/W-0 R/W-0 U-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-1
CMPL1 CMPL0 — STRSYNC STRD STRC STRB STRA
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7-6 CMPL<1:0>: Complementary Mode Output Assignment Steering Sync bits
00 = See STR<D:A>
01 = PA and PB are selected as the complementary output pair
10 = PA and PC are selected as the complementary output pair
11 = PA and PD are selected as the complementary output pair
bit 5 Unimplemented: Read as ‘0’
bit 4 STRSYNC: Steering Sync bit
1 = Output steering update occurs on the next PWM period
0 = Output steering update occurs at the beginning of the instruction cycle boundary
bit 3 STRD: Steering Enable bit D
1 = PxD pin has the PWM waveform with polarity control from CCPxM<1:0>
0 = PxD pin is assigned to port pin
bit 2 STRC: Steering Enable bit C
1 = PxC pin has the PWM waveform with polarity control from CCPxM<1:0>
0 = PxC pin is assigned to port pin
bit 1 STRB: Steering Enable bit B
1 = PxB pin has the PWM waveform with polarity control from CCPxM<1:0>
0 = PxB pin is assigned to port pin
bit 0 STRA: Steering Enable bit A
1 = PxA pin has the PWM waveform with polarity control from CCPxM<1:0>
0 = PxA pin is assigned to port pin
Note 1: The PWM Steering mode is available only when the CCPxCON register bits, CCPxM<3:2> = 11 and
PxM<1:0> = 00.
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FIGURE 20-16 : SI MPL IFI ED STEERING
BLOCK DIAGRAM 20.4.7.1 Steering Synchronization
The STRSYNC bit of the PSTRxCON register gives the
user two choices for when the steering event will
happen. When the STRSYNC bit is ‘0’, the steering
event will happen at the end of the instruction that
writes to the PSTRxCON register. In this case, the out-
put signal at the Px<D:A> pins may be an incomplete
PWM waveform. This operation is useful when the user
firmware needs to immediately remove a PWM signal
from the pin.
When the STRSYNC bit is ‘1’, the effective steering
update will happen at the beginning of the next PWM
period. In this case, steering on/off the PWM output will
always produce a complete PWM waveform.
Figures 20-17 and 20-18 illustrate the timing diagrams
of the PWM steering depending on the STRSYNC
setting.
FIGURE 20-17: EXAMP LE OF STEERING EVENT AT END OF INSTRUCTION (STRSYNC = 0)
FIGURE 20-18: EXAMPLE OF STEERING EVENT AT BEGINNING OF INSTRUCTION (STRSYNC = 1)
1
0TRIS
Output Pin(1)
PORT Data
PxA Signal
STRA(2)
1
0TRIS
Output Pin(1)
PORT Data
STRB(2)
1
0
TRIS
Output Pin(1)
PORT Data
STRC(2)
1
0TRIS
Output Pin(1)
PORT Data
STRD(2)
Note 1: Port outputs are configured as displayed when
the CCPxCON register bits, PxM<1:0> = 00
and CCP1M<3:2> = 11.
2: Single PWM output requires setting at least
one of the STRx bits.
CCPxM1
CCPxM0
CCPxM1
CCPxM0
PWM
P1n = PWM
STRn
P1<D:A> PORT Data
PWM Period
PORT Data
PWM
PORT Data
P1n = PWM
STRn
P1<D:A> PORT Data
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20.4.8 OPERATION IN POWER-MANAGED
MODES
In Sleep mode, all clock sources are disabled.
Timer2/4/6/8 will not increment and the state of the
module will not change. If the ECCPx pin is driving a
value, it will continue to drive that value. When the
device wakes up, it will continue from this state. If
Two-Speed Start-ups are enabled, the initial start-up
frequency from HF-INTOSC and the postscaler may
not be stable immediately.
In PRI_IDLE mode, the primary clock will continue to
clock the ECCPx module without change.
20.4.8.1 Operation with Fail-Safe
Clock Monitor (FSCM)
If the Fail-Safe Clock Monitor (FSCM) is enabled, a clock
failure will force the device into the power-managed
RC_RUN mode and the OSCFIF bit of the PIR2 register
will be set. The ECCPx will then be clocked from the
internal oscillator clock source, which may have a
different clock frequency than the primary clock.
20.4.9 EFFECTS OF A RESET
Both Power-on Reset and subsequent Resets will force
all ports to Input mode and the ECCP registers to their
Reset states.
This forces the ECCP module to reset to a state
compatible with previous, non-enhanced CCP modules
used on other PIC18 and PIC16 devices.
TABLE 20-4: REGISTERS ASSOCIATED WITH ECCP1/2/3 MODULE AND
TIMER1/2/3/4/6/8/10/12
File Name B it 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
INTCON GIE/GIEH PEIE/GIEL TMR0IE INT0IE RBIE TMR0IF INT0IF RBIF
RCON IPEN SBOREN CM RI TO PD POR BOR
PIR3 TMR5GIF —RC2IF TX2IF CTMUIF CCP2IF CCP1IF RTCCIF
PIR4 CCP10IF(1) CCP9IF(1) CCP8IF CCP7IF CCP6IF CCP5IF CCP4IF CCP3IF
PIE3 TMR5GIE —RC2IE TX2IE CTMUIE CCP2IE CCP1IE RTCCIE
PIE4 CCP10IE(1) CCP9IE(1) CCP8IE CCP7IE CCP6IE CCP5IE CCP4IE CCP3IE
IPR3 TMR5GIP —RC2IP TX2IP CTMUIP CCP2IP CCP1IP RTCCIP
IPR4 CCP10IP(1) CCP9IP(1) CCP8IP CCP7IP CCP6IP CCP5IP CCP4IP CCP3IP
TRISB TRISB7 TRISB6 TRISB5 TRISB4 TRISB3 TRISB2 TRISB1 TRISB0
TRISC TRISC7 TRISC6 TRISC5 TRISC4 TRISC3 TRISC2 TRISC1 TRISC0
TRISE TRISE7 TRISE6 TRISE5 TRISE4 TRISE3 TRISE2 TRISE1 TRISE0
TRISH(2) TRISH7 TRISH6 TRISH5 TRISH4 TRISH3 TRISH2 TRISH1 TRISH0
TMR1H Timer1 Register High Byte
TMR1L Timer1 Register Low Byte
TMR2 Timer2 Register
TMR3H Timer3 Register High Byte
TMR3L Timer3 Register Low Byte
TMR4 Timer4 Register
TMR6 Timer6 Register
TMR8 Timer8 Register
TMR10(1) TMR10 Register
TMR12(1) TMR10 Register
PR2 Timer2 Period Register
PR4 Timer4 Period Register
PR6 Timer6 Period Register
PR8 Timer8 Period Register
PR10(1) Timer10 Period Register
PR12(1) Timer12 Period Register
Note 1: Unimplemented on devices with a program memory of 32 Kbytes (PIC18F65K22 and PIC18F85K22).
2: Unimplemented on 64-pin devices (PIC18F6XK22), read as ‘0’.
PIC18F87K22 FAMILY
DS39960C-page 280 2011 Microchip Technology Inc.
T1CON TMR1CS1 TMR1CS0 T1CKPS1 T1CKPS0 SOSCEN T1SYNC RD16 TMR1ON
T2CON — T2OUTPS3 T2OUTPS2 T2OUTPS1 T2OUTPS0 TMR2ON T2CKPS1 T2CKPS0
T3CON TMR3CS1 TMR3CS0 T3CKPS1 T3CKPS0 SOSCEN T3SYNC RD16 TMR3ON
T4CON — T4OUTPS3 T4OUTPS2 T4OUTPS1 T4OUTPS0 TMR4ON T4CKPS1 T4CKPS0
T6CON — T6OUTPS3 T6OUTPS2 T6OUTPS1 T6OUTPS0 TMR6ON T6CKPS1 T6CKPS0
T8CON — T8OUTPS3 T8OUTPS2 T8OUTPS1 T8OUTPS0 TMR8ON T8CKPS1 T8CKPS0
T10CON(1) — T10OUTPS3 T10OUTPS2 T10OUTPS1 T10OUTPS0 TMR10ON T10CKPS1 T10CKPS0
T12CON(1) — T12OUTPS3 T12OUTPS2 T12OUTPS1 T12OUTPS0 TMR12ON T12CKPS1 T12CKPS0
CCPR1H Capture/Compare/PWM Register 1 High Byte
CCPR1L Capture/Compare/PWM Register 1 Low Byte
CCPR2H Capture/Compare/PWM Register 2 High Byte
CCPR2L Capture/Compare/PWM Register 2 Low Byte
CCPR3H Capture/Compare/PWM Register 3 High Byte
CCPR3L Capture/Compare/PWM Register 3 Low Byte
CCP1CON P1M1 P1M0 DC1B1 DC1B0 CCP1M3 CCP1M2 CCP1M1 CCP1M0
CCP2CON P2M1 P2M0 DC2B1 DC2B0 CCP2M3 CCP2M2 CCP2M1 CCP2M0
CCP3CON CCP3MD CCP2MD CCP1MD UART2MD UART1MD SSP2MD SSP1MD ADCMD
PMD0 CCP3MD CCP2MD CCP1MD UART2MD UART1MD SSP2MD SSP1MD ADCMD
TABLE 20-4: REGISTERS ASSOCIATED WITH ECCP1/2/3 MODULE AND
TIMER1/2/3/4/6/8/10/12 (CONTINUED)
File Name B it 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
Note 1: Unimplemented on devices with a program memory of 32 Kbytes (PIC18F65K22 and PIC18F85K22).
2: Unimplemented on 64-pin devices (PIC18F6XK22), read as ‘0’.
2011 Microchip Technology Inc. DS39960C-page 281
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21.0 MASTER SYNCHRONOUS
SERIAL PORT (MS SP)
MODULE
21.1 Master SSP (MSSP) Module
Overview
The Master Synchronous Serial Port (MSSP) module is
a serial interface, useful for communicating with other
peripheral or microcontroller devices. These peripheral
devices may be serial EEPROMs, shift registers,
display drivers, A/D Converters, etc. The MSSP
module can operate in one of two modes:
• Serial Peripheral Interface (SPI)
• Inter-Integrated Circuit™ (I2C™)
- Full Master mode
- Slave mode (with general address call)
The I2C interface supports the following modes in
hardware:
•Master mode
• Multi-Master mode
• Slave mode with 5-bit and 7-bit address masking
(with address masking for both 10-bit and 7-bit
addressing)
All members of the PIC18F87K22 family have two
MSSP modules, designated as MSSP1 and MSSP2.
Each module operates independently of the other.
21.2 Control Registers
Each MSSP module has three associated control regis-
ters. These include a status register (SSPxSTAT) and
two control registers (SSPxCON1 and SSPxCON2). The
use of these registers and their individual configuration
bits differ significantly depending on whether the MSSP
module is operated in SPI or I2C mode.
Additional details are provided under the individual
sections.
21.3 SPI Mode
The SPI mode allows 8 bits of data to be synchronously
transmitted and received simultaneously. All four
modes of SPI are supported. To accomplish
communication, typically three pins are used:
• Serial Data Out (SDOx) – RC5/SDO1 or
RD4/PSP4/SDO2
• Serial Data In (SDIx) – RC4/SDI1/SDA1 or
RD5/PSP5/SDI2/SDA2
• Serial Clock (SCKx) – RC3/SCK1/SCL1 or
RD6/PSP6/SCK2/SCL2
Additionally, a fourth pin may be used when in a Slave
mode of operation:
• Slave Select (SSx) – RF7/AN5/SS1 or RD7/SS2
Figure 21-1 shows the block diagram of the MSSP
module when operating in SPI mode.
FIGURE 21-1: MSSP BLOCK DIAGRAM
(SPI MODE)
Note: Throughout this section, generic refer-
ences to an MSSP module in any of its
operating modes may be interpreted as
being equally applicable to MSSP1 or
MSSP2. Register names and module I/O
signals use the generic designator ‘x’ to
indicate the use of a numeral to distinguish
a particular module when required. Control
bit names are not individuated.
Note: In devices with more than one MSSP
module, it is very important to pay close
attention to SSPxCON register names.
SSP1CON1 and SSP1CON2 control
different operational aspects of the same
module, while SSP1CON1 and
SSP2CON1 control the same features for
two different modules.
Note: The SSPxBUF register cannot be used with
read-modify-write instructions, such as BCF,
COMF, etc.
To avoid lost data in Master mode, a read of
the SSPxBUF must be performed to clear the
Buffer Full (BF) detect bit (SSPSTAT<0>)
between each transmission.
( )
Read Write
Internal
Data Bus
SSPxSR reg
SSPM<3:0>
bit 0 Shift
Clock
SSx Control
Enable
Edge
Select
Clock Select
TMR2 Output
TOSC
Prescaler
4, 16, 64
2
Edge
Select
2
4
Data to TXx/RXx in SSPxSR
TRIS bit
2
SMP:CKE
SDOx
SSPxBUF reg
SDIx
SSx
SCKx
Note: Only port I/O names are used in this diagram for the
sake of brevity. Refer to the text for a full list of
multiplexed functions.
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DS39960C-page 282 2011 Microchip Technology Inc.
21.3.1 REGISTERS
Each MSSP module has four registers for SPI mode
operation. These are:
• MSSPx Control Register 1 (SSPxCON1)
• MSSPx Status Register (SSPxSTAT)
• Serial Receive/Transmit Buffer Register
(SSPxBUF)
• MSSPx Shift Register (SSPxSR) – Not directly
accessible
SSPxCON1 and SSPxSTAT are the control and status
registers in SPI mode operation. The SSPxCON1
register is readable and writable. The lower 6 bits of
the SSPxSTAT are read-only. The upper two bits of the
SSPxSTAT are read/write.
SSPxSR is the shift register used for shifting data in or
out. SSPxBUF is the buffer register to which data
bytes are written to or read from.
In receive operations, SSPxSR and SSPxBUF
together create a double-buffered receiver. When
SSPxSR receives a complete byte, it is transferred to
SSPxBUF and the SSPxIF interrupt is set.
During transmission, the SSPxBUF is not
double-buffered. A write to SSPxBUF will write to both
SSPxBUF and SSPxSR.
REGIST ER 21-1: SSPx STAT: MS SP x STATUS REG IS TER (S PI MODE )
R/W-0 R/W-0 R-0 R-0 R-0 R-0 R-0 R-0
SMP CKE(1) D/A PSR/WUA BF
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 SMP: Sample bit
SPI Master mode:
1 = Input data is sampled at the end of data output time
0 = Input data is sampled at the middle of data output time
SPI Slave mode:
SMP must be cleared when SPI is used in Slave mode.
bit 6 CKE: SPI Clock Select bit(1)
1 = Transmit occurs on the transition from active to Idle clock state
0 = Transmit occurs on the transition from Idle to active clock state
bit 5 D/A: Data/Address bit
Used in I2C™ mode only.
bit 4 P: Stop bit
Used in I2C mode only. This bit is cleared when the MSSPx module is disabled; SSPEN is cleared.
bit 3 S: Start bit
Used in I2C mode only.
bit 2 R/W: Read/Write Information bit
Used in I2C mode only.
bit 1 UA: Update Address bit
Used in I2C mode only.
bit 0 BF: Buffer Full Status bit (Receive mode only)
1 = Receive is complete, SSPxBUF is full
0 = Receive is not complete, SSPxBUF is empty
Note 1: Polarity of clock state is set by the CKP bit (SSPxCON1<4>).
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REGISTER 21-2: SSPxCON1: MSSPx CONTROL REGISTER 1 (SPI MODE)
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0
WCOL SSPOV(1) SSPEN(2) CKP SSPM3(3) SSPM2(3) SSPM1(3) SSPM0(3)
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 WCOL: Write Collision Detect bit
1 = The SSPxBUF register is written while it is still transmitting the previous word (must be cleared in
software)
0 = No collision
bit 6 SSPOV: Receive Overflow Indicator bit(1)
SPI Slave mode:
1 = A new byte is received while the SSPxBUF register is still holding the previous data. In case of
overflow, the data in SSPxSR is lost. Overflow can only occur in Slave mode. The user must read
the SSPxBUF, even if only transmitting data, to avoid setting overflow (must be cleared in
software).
0 = No overflow
bit 5 SSPEN: Master Synchronous Serial Port Enable bit(2)
1 = Enables serial port and configures SCKx, SDOx, SDIx and SSx as serial port pins
0 = Disables serial port and configures these pins as I/O port pins
bit 4 CKP: Clock Polarity Select bit
1 = Idle state for the clock is a high level
0 = Idle state for the clock is a low level
bit 3-0 SSPM<3:0>: Master Synchronous Serial Port Mode Select bits(3)
1010 = SPI Master mode: clock = FOSC/8
0101 = SPI Slave mode: clock = SCKx pin; SSx pin control disabled; SSx can be used as I/O pin
0100 = SPI Slave mode: clock = SCKx pin; SSx pin control enabled
0011 = SPI Master mode: clock = TMR2 output/2
0010 = SPI Master mode: clock = FOSC/64
0001 = SPI Master mode: clock = FOSC/16
0000 = SPI Master mode: clock = FOSC/4
Note 1: In Master mode, the overflow bit is not set since each new reception (and transmission) is initiated by
writing to the SSPxBUF register.
2: When enabled, these pins must be properly configured as inputs or outputs.
3: Bit combinations not specifically listed here are either reserved or implemented in I2C™ mode only.
PIC18F87K22 FAMILY
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21.3.2 OPERATION
When initializing the SPI, several options need to be
specified. This is done by programming the appropriate
control bits (SSPxCON1<5:0> and SSPxSTAT<7:6>).
These control bits allow the following to be specified:
• Master mode (SCKx is the clock output)
• Slave mode (SCKx is the clock input)
• Clock Polarity (Idle state of SCKx)
• Data Input Sample Phase (middle or end of data
output time)
• Clock Edge (output data on rising/falling edge of
SCKx)
• Clock Rate (Master mode only)
• Slave Select mode (Slave mode only)
Each MSSP module consists of a Transmit/Receive
Shift register (SSPxSR) and a buffer register
(SSPxBUF). The SSPxSR shifts the data in and out of
the device, MSb first. The SSPxBUF holds the data that
was written to the SSPxSR until the received data is
ready. Once the 8 bits of data have been received, that
byte is moved to the SSPxBUF register. Then, the
Buffer Full detect bit, BF (SSPxSTAT<0>), and the
interrupt flag bit, SSPxIF, are set. This double-buffering
of the received data (SSPxBUF) allows the next byte to
start reception before reading the data that was just
received. Any write to the SSPxBUF register during
transmission/reception of data will be ignored and the
Write Collision Detect bit, WCOL (SSPxCON1<7>), will
be set. User software must clear the WCOL bit so that
it can be determined if the following write(s) to the
SSPxBUF register completed successfully.
When the application software is expecting to receive
valid data, the SSPxBUF should be read before the next
byte of data to transfer is written to the SSPxBUF. The
Buffer Full bit, BF (SSPxSTAT<0>), indicates when
SSPxBUF has been loaded with the received data
(transmission is complete). When the SSPxBUF is read,
the BF bit is cleared. This data may be irrelevant if the
SPI is only a transmitter. Generally, the MSSP interrupt
is used to determine when the transmission/reception
has completed. If the interrupt method is not going to be
used, then software polling can be done to ensure that a
write collision does not occur. Example 21-1 shows the
loading of the SSPxBUF (SSPxSR) for data
transmission.
The SSPxSR is not directly readable or writable and
can only be accessed by addressing the SSPxBUF
register. Additionally, the SSPxSTAT register indicates
the various status conditions.
21.3.3 OPEN-DRAIN OUTPUT OPTION
The drivers for the SDOx output and SCKx clock pins
can be optionally configured as open-drain outputs.
This feature allows the voltage level on the pin to be
pulled to a higher level through an external pull-up
resistor, and allows the output to communicate with
external circuits without the need for additional level
shifters. For more information, see Section 12.1.3
“Open-Drain Outputs”.
The open-drain output option is controlled by the
SSP2OD and SSP1OD bits (ODCON3<1:0>). Setting
an SSPxOD bit configures the SDOx and SCKx pins for
the corresponding module for open-drain operation.
EXAMPLE 21-1: LOADING THE SSP1BUF (SSP1SR ) REGISTER
Note: To avoid lost data in Master mode, a
read of the SSPxBUF must be per-
formed to clear the Buffer Full (BF)
detect bit (SSPxSTAT<0>) between
each transmission.
LOOP BTFSS SSP1STAT, BF ;Has data been received (transmit complete)?
BRA LOOP ;No
MOVF SSP1BUF, W ;WREG reg = contents of SSP1BUF
MOVWF RXDATA ;Save in user RAM, if data is meaningful
MOVF TXDATA, W ;W reg = contents of TXDATA
MOVWF SSP1BUF ;New data to xmit
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21.3.4 ENABLING SPI I/O
To enable the serial port, MSSP Enable bit, SSPEN
(SSPxCON1<5>), must be set. To reset or reconfigure
SPI mode, clear the SSPEN bit, re-initialize the
SSPxCON registers and then set the SSPEN bit. This
configures the SDIx, SDOx, SCKx and SSx pins as
serial port pins. For the pins to behave as the serial port
function, some must have their data direction bits (in
the TRIS register) appropriately programmed as
follows:
• SDIx is automatically controlled by the
SPI module
• SDOx must have the TRISC<5> or TRISD<4> bit
cleared
• SCKx (Master mode) must have the TRISC<3> or
TRISD<6>bit cleared
• SCKx (Slave mode) must have the TRISC<3> or
TRISD<6> bit set
• SSx must have the TRISF<7> or TRISD<7> bit set
Any serial port function that is not desired may be
overridden by programming the corresponding Data
Direction (TRIS) register to the opposite value.
21.3.5 TYPICAL CONNECTION
Figure 21-2 shows a typical connection between two
microcontrollers. The master controller (Processor 1)
initiates the data transfer by sending the SCKx signal.
Data is shifted out of both shift registers on their pro-
grammed clock edge and latched on the opposite edge
of the clock. Both processors should be programmed to
the same Clock Polarity (CKP), then both controllers
would send and receive data at the same time.
Whether the data is meaningful (or dummy data)
depends on the application software. This leads to
three scenarios for data transmission:
• Master sends data–Slave sends dummy data
• Master sends data–Slave sends data
• Master sends dummy data–Slave sends data
FIGURE 21-2: SP I MAST ER /S LAVE CONNECTION
Serial Input Buffer
(SSPxBUF)
Shift Register
(SSPxSR)
MSb LSb
SDOx
SDIx
PROCESSOR 1
SCKx
SPI Master SSPM<3:0> = 00xxb
Serial Input Buffer
(SSPxBUF)
Shift Register
(SSPxSR)
LSb
MSb
SDIx
SDOx
PROCESSOR 2
SCKx
SPI Slave SSPM<3:0> = 010xb
Serial Clock
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21.3.6 MASTER MODE
The master can initiate the data transfer at any time
because it controls the SCKx. The master determines
when the slave (Processor 1, Figure 21-2) is to
broadcast data by the software protocol.
In Master mode, the data is transmitted/received as
soon as the SSPxBUF register is written to. If the SPI
is only going to receive, the SDOx output could be dis-
abled (programmed as an input). The SSPxSR register
will continue to shift in the signal present on the SDIx
pin at the programmed clock rate. As each byte is
received, it will be loaded into the SSPxBUF register as
if a normal received byte (interrupts and status bits
appropriately set). This could be useful in receiver
applications as a “Line Activity Monitor” mode.
The clock polarity is selected by appropriately
programming the CKP bit (SSPxCON1<4>). This, then,
would give waveforms for SPI communication, as
shown in Figure 21-3, Figure 21-5 and Figure 21-6,
where the MSB is transmitted first. In Master mode, the
SPI clock rate (bit rate) is user-programmable to be one
of the following:
•F
OSC/4 (or TCY)
•FOSC/16 (or 4 • TCY)
•F
OSC/64 (or 16 • TCY)
• Timer2 output/2
This allows a maximum data rate (at 40 MHz) of
10.00 Mbps.
Figure 21-3 shows the waveforms for Master mode.
When the CKE bit is set, the SDOx data is valid before
there is a clock edge on SCKx. The change of the input
sample is shown based on the state of the SMP bit. The
time when the SSPxBUF is loaded with the received
data is shown.
FIGURE 21-3: SPI MODE WAVEFORM (MASTER MODE)
SCKx
(CKP = 0
SCKx
(CKP = 1
SCKx
(CKP = 0
SCKx
(CKP = 1
4 Clock
Modes
Input
Sample
Input
Sample
SDIx
bit 7 bit 0
SDOx bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0
bit 7
SDIx
SSPxIF
(SMP = 1)
(SMP = 0)
(SMP = 1)
CKE = 1)
CKE = 0)
CKE = 1)
CKE = 0)
(SMP = 0)
Write to
SSPxBUF
SSPxSR to
SSPxBUF
SDOx bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0
(CKE = 0)
(CKE = 1)
Next Q4 Cycle
after Q2
bit 0
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21.3.7 SLAVE MODE
In Slave mode, the data is transmitted and received as
the external clock pulses appear on SCKx. When the
last bit is latched, the SSPxIF interrupt flag bit is set.
While in Slave mode, the external clock is supplied by
the external clock source on the SCKx pin. This
external clock must meet the minimum high and low
times as specified in the electrical specifications.
While in Sleep mode, the slave can transmit/receive
data. When a byte is received, the device can be
configured to wake-up from Sleep.
21.3.8 SLAVE SELECT
SYNCHRONIZATION
The SSx pin allows a Synchronous Slave mode. The
SPI must be in Slave mode with the SSx pin control
enabled (SSPxCON1<3:0> = 04h). When the SSx pin
is low, transmission and reception are enabled and the
SDOx pin is driven. When the SSx pin goes high, the
SDOx pin is no longer driven, even if in the middle of a
transmitted byte and becomes a floating output.
External pull-up/pull-down resistors may be desirable
depending on the application.
When the SPI module resets, the bit counter is forced
to ‘0’. This can be done by either forcing the SSx pin to
a high level or clearing the SSPEN bit.
To emulate two-wire communication, the SDOx pin can
be connected to the SDIx pin. When the SPI needs to
operate as a receiver, the SDOx pin can be configured
as an input. This disables transmissions from the
SDOx. The SDIx can always be left as an input (SDIx
function) since it cannot create a bus conflict.
FIGURE 21-4: SLAV E SYNCHRONIZATION WAVEFORM
Note: When the SPI is in Slave mode with SSx pin
control enabled (SSPxCON1<3:0> = 0100),
the SPI module will reset if the SSx pin is set
to VDD.
If the SPI is used in Slave mode with CKE
set, then the SSx pin control must be
enabled.
SCKx
(CKP = 1
SCKx
(CKP = 0
Input
Sample
SDIx
bit 7
SDOx bit 7 bit 6 bit 7
SSPxIF
Interrupt
(SMP = 0)
CKE = 0)
CKE = 0)
(SMP = 0)
Write to
SSPxBUF
SSPxSR to
SSPxBUF
SSx
Flag
bit 0
bit 7
bit 0
Next Q4 Cycle
after Q2
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DS39960C-page 288 2011 Microchip Technology Inc.
FIGURE 21-5: SPI MODE WAVEFORM (SLAVE MODE WITH CKE = 0)
FIGURE 21-6: SPI MODE WAVEFORM (SLAVE MODE WITH CKE = 1)
SCKx
(CKP = 1
SCKx
(CKP = 0
Input
Sample
SDIx
bit 7
SDOx bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0
SSPxIF
Interrupt
(SMP = 0)
CKE = 0)
CKE = 0)
(SMP = 0)
Write to
SSPxBUF
SSPxSR to
SSPxBUF
SSx
Flag
Optional
Next Q4 Cycle
after Q2
bit 0
SCKx
(CKP = 1
SCKx
(CKP = 0
Input
Sample
SDIx
bit 7 bit 0
SDOx bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0
SSPxIF
Interrupt
(SMP = 0)
CKE = 1)
CKE = 1)
(SMP = 0)
Write to
SSPxBUF
SSPxSR to
SSPxBUF
SSx
Flag
Not Optional
Next Q4 Cycle
after Q2
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21.3.9 OPERATION IN POWER-MANAGED
MODES
In SPI Master mode, module clocks may be operating
at a different speed than when in full-power mode. In
the case of Sleep mode, all clocks are halted.
In Idle modes, a clock is provided to the peripherals.
That clock can be from the primary clock source, the
secondary clock (SOSC oscillator) or the INTOSC
source. See Section 3.3 “Clock Sources and
Oscillato r Switchin g” for additional information.
In most cases, the speed that the master clocks SPI
data is not important; however, this should be
evaluated for each system.
If MSSP interrupts are enabled, they can wake the con-
troller from Sleep mode, or one of the Idle modes, when
the master completes sending data. If an exit from
Sleep or Idle mode is not desired, MSSP interrupts
should be disabled.
If the Sleep mode is selected, all module clocks are
halted and the transmission/reception will remain in
that state until the device wakes. After the device
returns to Run mode, the module will resume
transmitting and receiving data.
In SPI Slave mode, the SPI Transmit/Receive Shift
register operates asynchronously to the device. This
allows the device to be placed in any power-managed
mode and data to be shifted into the SPI
Transmit/Receive Shift register. When all 8 bits have
been received, the MSSP interrupt flag bit will be set,
and if enabled, will wake the device.
21.3.10 EFFECTS OF A RESET
A Reset disables the MSSP module and terminates the
current transfer.
21.3.11 BUS MODE COMPATIBILITY
Table 21-1 shows the compatibility between the
standard SPI modes and the states of the CKP and
CKE control bits.
TABLE 21-1: SPI BUS MODES
There is also an SMP bit which controls when the data
is sampled.
21.3.12 SPI CLOCK SPEED AND MODULE
INTERACTIONS
Because MSSP1 and MSSP2 are independent
modules, they can operate simultaneously at different
data rates. Setting the SSPM<3:0> bits of the
SSPxCON1 register determines the rate for the
corresponding module.
An exception is when both modules use Timer2 as a
time base in Master mode. In this instance, any
changes to the Timer2 module’s operation will affect
both MSSP modules equally. If different bit rates are
required for each module, the user should select one of
the other three time base options for one of the
modules.
Standard SPI Mode
Terminology
Control Bits State
CKP CKE
0, 0 0 1
0, 1 0 0
1, 0 1 1
1, 1 1 0
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TABLE 21-2: REGISTERS ASSOCIATED WITH SPI OPERATION
Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
INTCON GIE/GIEH PEIE/GIEL TMR0IE INT0IE RBIE TMR0IF INT0IF RBIF
PIR2 OSCFIF — SSP2IF BCL2IF BCL1IF HLVDIF TMR3IF TMR3GIF
PIE2 OSCFIE — SSP2IE BCL2IE BCL1IE HLVDIE TMR3IE TMR3GIE
IPR2 OSCFIP — SSP2IP BCL2IP BCL1IP HLVDIP TMR3IP TMR3GIP
PIR3 TMR5GIF —RC2IF TX2IF CTMUIF CCP2IF CCP1IF RTCCIF
PIE3 TMR5GIE —RC2IE TX2IE CTMUIE CCP2IE CCP1IE RTCCIE
IPR3 TMR5GIP —RC2IP TX2IP CTMUIP CCP2IP CCP1IP RTCCIP
TRISC TRISC7 TRISC6 TRISC5 TRISC4 TRISC3 TRISC2 TRISC1 TRISC0
TRISD TRISD7 TRISD6 TRISD5 TRISD4 TRISD3 TRISD2 TRISD1 TRISD0
TRISF TRISF7 TRISF6 TRISF5 TRISF4 TRISF3 TRISF2 TRISF1 —
SSP1BUF MSSP1 Receive Buffer/Transmit Register
SSP1CON1 WCOL SSPOV SSPEN CKP SSPM3 SSPM2 SSPM1 SSPM0
SSP1CON2 GCEN ACKSTAT ACKDT ACKEN RCEN PEN RSEN SEN
SSP1STAT SMP CKE D/A P S R/W UA BF
SSP2CON1 WCOL SSPOV SSPEN CKP SSPM3 SSPM2 SSPM1 SSPM0
SSP2CON2 GCEN ACKSTAT ACKDT ACKEN RCEN PEN RSEN SEN
SSP2STAT SMP CKE D/A P S R/W UA BF
SSP2BUF MSSP2 Receive Buffer/Transmit Register
ODCON1 SSP1OD CCP2OD CCP1OD — — — — SSP2OD
PMD0 CCP3MD CCP2MD CCP1MD UART2MD UART1MD SSP2MD SSP1MD ADCMD
Legend: Shaded cells are not used by the MSSP module in SPI mode.
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21.4 I2C Mode
The MSSP module in I2C mode fully implements all
master and slave functions (including general call
support), and provides interrupts on Start and Stop bits
in hardware to determine a free bus (multi-master
function). The MSSP module implements the standard
mode specifications, as well as 7-bit and 10-bit
addressing.
Two pins are used for data transfer:
• Serial Clock (SCLx) – RC3/SCK1/SCL1 or
RD6/SCK2/SCL2
• Serial Data (SDAx) – RC4/SDI1/SDA1 or
RD5/SDI2/SDA2
The user must configure these pins as inputs by setting
the associated TRIS bits.
FIGURE 21-7: MSSP BLOCK DIAGRAM
(I2C™ MODE)
21.4.1 REGISTERS
The MSSP module has seven registers for I2C
operation. These are:
• MSSPx Control Register 1 (SSPxCON1)
• MSSPx Control Register 2 (SSPxCON2)
• MSSPx Status Register (SSPxSTAT)
• Serial Receive/Transmit Buffer Register
(SSPxBUF)
• MSSPx Shift Register (SSPxSR) – Not directly
accessible
• MSSPx Address Register (SSPxADD)
•I
2C Slave Address Mask Register (SSPxMSK)
SSPxCON1, SSPxCON2 and SSPxSTAT are the
control and status registers in I2C mode operation. The
SSPxCON1 and SSPxCON2 registers are readable and
writable. The lower 6 bits of the SSPxSTAT are
read-only. The upper two bits of the SSPxSTAT are
read/write.
SSPxSR is the shift register used for shifting data in or
out. SSPxBUF is the buffer register to which data
bytes are written to or read from.
SSPxADD contains the slave device address when the
MSSP is configured in I2C Slave mode. When the
MSSP is configured in Master mode, the lower seven
bits of SSPxADD act as the Baud Rate Generator
reload value.
SSPxMSK holds the slave address mask value when
the module is configured for 7-bit Address Masking
mode. While it is a separate register, it shares the same
SFR address as SSPxADD; it is only accessible when
the SSPM<3:0> bits are specifically set to permit
access. Additional details are provided in
Section 21.4.3.4 “7-Bit Address Masking Mode”.
In receive operations, SSPxSR and SSPxBUF
together, create a double-buffered receiver. When
SSPxSR receives a complete byte, it is transferred to
SSPxBUF and the SSPxIF interrupt is set.
During transmission, the SSPxBUF is not
double-buffered. A write to SSPxBUF will write to both
SSPxBUF and SSPxSR.
Read Write
SSPxSR reg
Match Detect
SSPxADD reg
SSPxBUF reg
Internal
Data Bus
Addr Match
Set, Reset
S, P bits
(SSPxSTAT reg)
Shift
Clock
MSb LSb
Note: Only port I/O names are used in this diagram for
the sake of brevity. Refer to the text for a full list of
multiplexed functions.
SCLx
SDAx
Start and
Stop bit Detect
Address Mask
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REGIST ER 21-3: SSPx STAT: MS SP x STATUS REGISTER (I 2C™ MODE)
R/W-0 R/W-0 R-0 R-0 R-0 R-0 R-0 R-0
SMP CKE D/A P(1) S(1) R/W(2,3) UA BF
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 SMP: Slew Rate Control bit
In Master or Slave mode:
1 = Slew rate control disabled for Standard Speed mode (100 kHz and 1 MHz)
0 = Slew rate control enabled for High-Speed mode (400 kHz)
bit 6 CKE: SMBus Select bit
In Master or Slave mode:
1 = Enable SMBus-specific inputs
0 = Disable SMBus-specific inputs
bit 5 D/A: Data/Address bit
In Master mode:
Reserved.
In Slave mode:
1 = Indicates that the last byte received or transmitted was data
0 = Indicates that the last byte received or transmitted was address
bit 4 P: Stop bit(1)
1 = Indicates that a Stop bit has been detected last
0 = Stop bit was not detected last
bit 3 S: Start bit(1)
1 = Indicates that a Start bit has been detected last
0 = Start bit was not detected last
bit 2 R/W: Read/Write Information bit(2,3)
In Slave mode:
1 = Read
0 = Write
In Master mode:
1 = Transmit is in progress
0 = Transmit is not in progress
bit 1 UA: Update Address bit (10-Bit Slave mode only)
1 = Indicates that the user needs to update the address in the SSPxADD register
0 = Address does not need to be updated
bit 0 BF: Buffer Full Status bit
In Transmit mode:
1 = SSPxBUF is full
0 = SSPxBUF is empty
In Receive mode:
1 = SSPxBUF is full (does not include the ACK and Stop bits)
0 = SSPxBUF is empty (does not include the ACK and Stop bits)
Note 1: This bit is cleared on Reset and when SSPEN is cleared.
2: This bit holds the R/W bit information following the last address match. This bit is only valid from the
address match to the next Start bit, Stop bit or not ACK bit.
3: ORing this bit with SEN, RSEN, PEN, RCEN or ACKEN will indicate if the MSSPx is in Active mode.
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REGISTER 21-4: SSPxCON1: MSSPx CONTROL REGISTER 1 (I2C™ MODE)
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0
WCOL SSPOV SSPEN(1) CKP SSPM3(2) SSPM2(2) SSPM1(2) SSPM0(2)
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 WCOL: Write Collision Detect bit
In Master Transmit mode:
1 = A write to the SSPxBUF register was attempted while the I2C conditions were not valid for a
transmission to be started (must be cleared in software)
0 = No collision
In Slave Transmit mode:
1 = The SSPxBUF register is written while it is still transmitting the previous word (must be cleared in
software)
0 = No collision
In Receive mode (Master or Slave modes):
This is a “don’t care” bit.
bit 6 SSPOV: Receive Overflow Indicator bit
In Receive mode:
1 = A byte is received while the SSPxBUF register is still holding the previous byte (must be cleared in
software)
0 = No overflow
In Transmit mode:
This is a “don’t care” bit in Transmit mode.
bit 5 SSPEN: Master Synchronous Serial Port Enable bit(1)
1 = Enables the serial port and configures the SDAx and SCLx pins as the serial port pins
0 = Disables serial port and configures these pins as I/O port pins
bit 4 CKP: SCKx Release Control bit
In Slave mode:
1 = Releases clock
0 = Holds clock low (clock stretch), used to ensure data setup time
In Master mode:
Unused in this mode.
bit 3-0 SSPM<3:0>: Master Synchronous Serial Port Mode Select bits(2)
1111 = I2C Slave mode: 10-bit address with Start and Stop bit interrupts enabled
1110 = I2C Slave mode: 7-bit address with Start and Stop bit interrupts enabled
1011 = I2C Firmware Controlled Master mode (slave Idle)
1001 = Load SSPMSK register at SSPxADD SFR address(3,4)
1000 = I2C Master mode: clock = FOSC/(4 * (SSPxADD + 1))
0111 = I2C Slave mode: 10-bit address
0110 = I2C Slave mode: 7-bit address
Note 1: When enabled, the SDAx and SCLx pins must be configured as inputs.
2: Bit combinations not specifically listed here are either reserved or implemented in SPI mode only.
3: When SSPM<3:0> = 1001, any reads or writes to the SSPxADD SFR address actually accesses the
SSPxMSK register.
4: This mode is only available when 7-Bit Address Masking mode is selected (MSSPMSK Configuration bit
is ‘1’).
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REGISTER 21-5: SSPxCON2: MSSPx CONTROL REGISTER 2 (I2C™ MASTER MODE)
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0
GCEN ACKSTAT ACKDT(1) ACKEN(2) RCEN(2) PEN(2) RSEN(2) SEN(2)
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 GCEN: General Call Enable bit
Unused in Master mode.
bit 6 ACKSTAT: Acknowledge Status bit (Master Transmit mode only)
1 = Acknowledge was not received from slave
0 = Acknowledge was received from slave
bit 5 ACKDT: Acknowledge Data bit (Master Receive mode only)(1)
1 = Not Acknowledge
0 = Acknowledge
bit 4 ACKEN: Acknowledge Sequence Enable bit(2)
1 = Initiates Acknowledge sequence on SDAx and SCLx pins and transmits ACKDT data bit.
Automatically cleared by hardware.
0 = Acknowledge sequence Idle
bit 3 RCEN: Receive Enable bit (Master Receive mode only)(2)
1 = Enables Receive mode for I2C™
0 = Receive is Idle
bit 2 PEN: Stop Condition Enable bit(2)
1 = Initiates Stop condition on SDAx and SCLx pins. Automatically cleared by hardware.
0 = Stop condition is Idle
bit 1 RSEN: Repeated Start Condition Enable bit(2)
1 = Initiates Repeated Start condition on SDAx and SCLx pins. Automatically cleared by hardware.
0 = Repeated Start condition is Idle
bit 0 SEN: Start Condition Enable bit(2)
1 = Initiates Start condition on SDAx and SCLx pins. Automatically cleared by hardware.
0 = Start condition is Idle
Note 1: Value that will be transmitted when the user initiates an Acknowledge sequence at the end of a receive.
2: If the I2C module is active, these bits may not be set (no spooling) and the SSPxBUF may not be written
(or writes to the SSPxBUF are disabled).
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REGISTER 21-6: SSPxCON2: MSSPx CONTROL REGISTER 2 (I2C™ SLAVE MODE)
REGISTER 21-7: SSPxMSK: I2C™ SLAVE ADDRESS MASK REGISTER (7-BIT MASKING MODE)(1)
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0
GCEN ACKSTAT ACKDT ACKEN(1) RCEN(1) PEN(1) RSEN(1) SEN(1)
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 GCEN: General Call Enable bit
1 = Enables interrupt when a general call address (0000h) is received in the SSPxSR
0 = General call address is disabled
bit 6 ACKSTAT: Acknowledge Status bit
Unused in Slave mode.
bit 5 ACKDT: Acknowledge Data bit (Master Receive mode only)(1)
1 = Not Acknowledge
0 = Acknowledge
bit 4 ACKEN: Acknowledge Sequence Enable bit(1)
1 = Initiates Acknowledge sequence on SDAx and SCLx pins and transmits ACKDT data bit.
Automatically cleared by hardware.
0 = Acknowledge sequence is Idle
bit 3 RCEN: Receive Enable bit (Master Receive mode only)(1)
1 = Enables Receive mode for I2C
0 = Receive is Idle
bit 2 PEN: Stop Condition Enable bit(1)
1 = Initiates Stop condition on SDAx and SCLx pins. Automatically cleared by hardware.
0 = Stop condition is Idle
bit 1 RSEN: Repeated Start Condition Enable bit(1)
1 = Initiates Repeated Start condition on SDAx and SCLx pins. Automatically cleared by hardware.
0 = Repeated Start condition is Idle
bit 0 SEN: Stretch Enable bit(1)
1 = Clock stretching is enabled for both slave transmit and slave receive (stretch enabled)
0 = Clock stretching is disabled
Note 1: If the I2C module is active, this bit may not be set (no spooling) and the SSPxBUF may not be written (or
writes to the SSPxBUF are disabled).
R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1
MSK7 MSK6 MSK5 MSK4 MSK3 MSK2 MSK1 MSK0(2)
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7-0 MSK<7:0>: Slave Address Mask Select bit
1 = Masking of corresponding bit of SSPxADD is enabled
0 = Masking of corresponding bit of SSPxADD is disabled
Note 1: This register shares the same SFR address as SSPxADD and is only addressable in select MSSPx
operating modes. See Section 21.4.3.4 “7-Bit Address Masking Mode” for more details.
2: MSK0 is not used as a mask bit in 7-bit addressing.
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21.4.2 OPERATION
The MSSP module functions are enabled by setting the
MSSP Enable bit, SSPEN (SSPxCON1<5>).
The SSPxCON1 register allows control of the I2C
operation. Four mode selection bits (SSPxCON1<3:0>)
allow one of the following I2C modes to be selected:
•I
2C Master mode, clock
•I
2C Slave mode (7-bit address)
•I
2C Slave mode (10-bit address)
•I
2C Slave mode (7-bit address) with Start and
Stop bit interrupts enabled
•I
2C Slave mode (10-bit address) with Start and
Stop bit interrupts enabled
•I
2C Firmware Controlled Master mode, slave is
Idle
Selection of any I2C mode with the SSPEN bit set
forces the SCLx and SDAx pins to be open-drain,
provided these pins are programmed as inputs by
setting the appropriate TRISC or TRISD bits. To ensure
proper operation of the module, pull-up resistors must
be provided externally to the SCLx and SDAx pins.
21.4.3 SLAVE MODE
In Slave mode, the SCLx and SDAx pins must be
configured as inputs (TRISC<4:3> set). The MSSP
module will override the input state with the output data
when required (slave-transmitter).
The I2C Slave mode hardware will always generate an
interrupt on an address match. Address masking will
allow the hardware to generate an interrupt for more
than one address (up to 31 in 7-bit addressing and up
to 63 in 10-bit addressing). Through the mode select
bits, the user can also choose to interrupt on Start and
Stop bits.
When an address is matched, or the data transfer after
an address match is received, the hardware auto-
matically will generate the Acknowledge (ACK) pulse
and load the SSPxBUF register with the received value
currently in the SSPxSR register.
Any combination of the following conditions will cause
the MSSP module not to give this ACK pulse:
• The Buffer Full bit, BF (SSPxSTAT<0>), was set
before the transfer was received.
• The overflow bit, SSPOV (SSPxCON1<6>), was
set before the transfer was received.
In this case, the SSPxSR register value is not loaded
into the SSPxBUF, but bit, SSPxIF, is set. The BF bit is
cleared by reading the SSPxBUF register, while bit,
SSPOV, is cleared through software.
The SCLx clock input must have a minimum high and
low for proper operation. The high and low times of the
I2C specification, as well as the requirement of the
MSSP module, are shown in timing Parameter 100 and
Parameter 101.
21.4.3.1 Addressing
Once the MSSP module has been enabled, it waits for
a Start condition to occur. Following the Start condition,
the 8 bits are shifted into the SSPxSR register. All
incoming bits are sampled with the rising edge of the
clock (SCLx) line. The value of register, SSPxSR<7:1>,
is compared to the value of the SSPxADD register. The
address is compared on the falling edge of the eighth
clock (SCLx) pulse. If the addresses match and the BF
and SSPOV bits are clear, the following events occur:
1. The SSPxSR register value is loaded into the
SSPxBUF register.
2. The Buffer Full bit, BF, is set.
3. An ACK pulse is generated.
4. The MSSP Interrupt Flag bit, SSPxIF, is set (and
interrupt is generated, if enabled) on the falling
edge of the ninth SCLx pulse.
In 10-Bit Addressing mode, two address bytes need to
be received by the slave. The five Most Significant bits
(MSbs) of the first address byte specify if this is a 10-bit
address. The R/W (SSPxSTAT<2>) bit must specify a
write so the slave device will receive the second
address byte. For a 10-bit address, the first byte would
equal ‘11110 A9 A8 0’, where ‘A9’ and ‘A8’ are the
two MSbs of the address. The sequence of events for
10-bit addressing is as follows, with steps, 7 through 9,
for the slave-transmitter:
1. Receive first (high) byte of address (bits,
SSPxIF, BF and UA, are set on address match).
2. Update the SSPxADD register with second (low)
byte of address (clears bit, UA, and releases the
SCLx line).
3. Read the SSPxBUF register (clears bit, BF) and
clear flag bit, SSPxIF.
4. Receive second (low) byte of address (bits,
SSPxIF, BF and UA, are set).
5. Update the SSPxADD register with the first
(high) byte of address. If match releases SCLx
line, this will clear bit, UA.
6. Read the SSPxBUF register (clears bit, BF) and
clear flag bit SSPxIF.
7. Receive Repeated Start condition.
8. Receive first (high) byte of address (bits,
SSPxIF and BF, are set).
9. Read the SSPxBUF register (clears bit, BF) and
clear flag bit, SSPxIF.
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21.4.3.2 Address Masking Modes
Masking an address bit causes that bit to become a
“don’t care”. When one address bit is masked, two
addresses will be Acknowledged and cause an
interrupt. It is possible to mask more than one address
bit at a time, which greatly expands the number of
addresses Acknowledged.
The I2C slave behaves the same way whether address
masking is used or not. However, when address
masking is used, the I2C slave can Acknowledge
multiple addresses and cause interrupts. When this
occurs, it is necessary to determine which address
caused the interrupt by checking the SSPxBUF.
The PIC18F87K22 family of devices is capable of using
two different Address Masking modes in I2C slave
operation: 5-Bit Address Masking and 7-Bit Address
Masking. The Masking mode is selected at device
configuration using the MSSPMSK Configuration bit.
The default device configuration is 7-Bit Address
Masking.
Both Masking modes, in turn, support address masking
of 7-bit and 10-bit addresses. The combination of
Masking modes and addresses provides different
ranges of Acknowledgable addresses for each
combination.
While both Masking modes function in roughly the
same manner, the way they use address masks are
different.
21.4.3.3 5-Bit Address Masking Mode
As the name implies, 5-Bit Address Masking mode
uses an address mask of up to 5 bits to create a range
of addresses to be Acknowledged, using bits, 5 through
1, of the incoming address. This allows the module to
Acknowledge up to 31 addresses when using 7-bit
addressing, or 63 addresses with 10-bit addressing
(see Example 21-2). This Masking mode is selected
when the MSSPMSK Configuration bit is programmed
(‘0’).
The address mask in this mode is stored in the
SSPxCON2 register, which stops functioning as a con-
trol register in I2C Slave mode (Register 21-6). In 7-Bit
Address Masking mode, address mask bits,
ADMSK<5:1> (SSPxCON2<5:1>), mask the corre-
sponding address bits in the SSPxADD register. For
any ADMSK bits that are set (ADMSK<n> = 1), the cor-
responding address bit is ignored (SSPxADD<n> = x).
For the module to issue an address Acknowledge, it is
sufficient to match only on addresses that do not have
an active address mask.
In 10-Bit Address Masking mode, bits, ADMSK<5:2>,
mask the corresponding address bits in the SSPxADD
register. In addition, ADMSK1 simultaneously masks
the two LSbs of the address (SSPxADD<1:0>). For any
ADMSK bits that are active (ADMSK<n> = 1), the cor-
responding address bit is ignored (SPxADD<n> = x).
Also note, that although in 10-Bit Address Masking
mode, the upper address bits reuse part of the
SSPxADD register bits. The address mask bits do not
interact with those bits; they only affect the lower
address bits.
EXAMPLE 21-2: ADDRESS MASKING EXAMPLES IN 5-BIT MASKING MODE
Note 1: ADMSK1 masks the two Least Significant
bits of the address.
2: The two Most Significant bits of the
address are not affected by address
masking.
7-Bit Addressing:
SSPxADD<7:1>= A0h (1010000) (SSPxADD<0> is assumed to be ‘0’)
ADMSK<5:1> = 00111
Addresses Acknowledged: A0h, A2h, A4h, A6h, A8h, AAh, ACh, AEh
10-Bit Addressing :
SSPxADD<7:0> = A0h (10100000) (The two MSb of the address are ignored in this example, since
they are not affected by masking)
ADMSK<5:1> = 00111
Addresses Acknowledged: A0h, A1h, A2h, A3h, A4h, A5h, A6h, A7h, A8h, A9h, AAh, ABh, ACh, ADh,
AEh, AFh
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21.4.3.4 7-Bit Address Masking Mode
Unlike 5-bit masking, 7-Bit Address Masking mode
uses a mask of up to 8 bits (in 10-bit addressing) to
define a range of addresses that can be Acknowl-
edged, using the lowest bits of the incoming address.
This allows the module to Acknowledge up to
127 different addresses with 7-bit addressing, or 255
with 10-bit addressing (see Example 21-3). This mode
is the default configuration of the module, which is
selected when MSSPMSK is unprogrammed (‘1’).
The address mask for 7-Bit Address Masking mode is
stored in the SSPxMSK register, instead of the
SSPxCON2 register. SSPxMSK is a separate hard-
ware register within the module, but it is not directly
addressable. Instead, it shares an address in the SFR
space with the SSPxADD register. To access the
SSPxMSK register, it is necessary to select MSSP
mode, ‘1001’ (SSPxCON1<3:0> = 1001) and then
read or write to the location of SSPxADD.
To use 7-Bit Address Masking mode, it is necessary to
initialize SSPxMSK with a value before selecting the
I2C Slave Addressing mode. Thus, the required
sequence of events is:
1. Select SSPxMSK Access mode
(SSPxCON2<3:0> = 1001).
2. Write the mask value to the appropriate
SSPADD register address (FC8h for MSSP1,
F6Eh for MSSP2).
3. Set the appropriate I2C Slave mode
(SSPxCON2<3:0> = 0111 for 10-bit addressing,
0110 for 7-bit addressing).
Setting or clearing mask bits in SSPxMSK behaves in
the opposite manner of the ADMSK bits in 5-Bit
Address Masking mode. That is, clearing a bit in
SSPxMSK causes the corresponding address bit to be
masked; setting the bit requires a match in that
position. SSPxMSK resets to all ‘1’s upon any Reset
condition and, therefore, has no effect on the standard
MSSP operation until written with a mask value.
With 7-bit addressing, SSPxMSK<7:1> bits mask the
corresponding address bits in the SSPxADD register.
For any SSPxMSK bits that are active
(SSPxMSK<n> = 0), the corresponding SSPxADD
address bit is ignored (SSPxADD<n> = x). For the
module to issue an address Acknowledge, it is
sufficient to match only on addresses that do not have
an active address mask.
With 10-bit addressing, SSPxMSK<7:0> bits mask the
corresponding address bits in the SSPxADD register.
For any SSPxMSK bits that are active (= 0), the corre-
sponding SSPxADD address bit is ignored
(SSPxADD<n> = x).
EXAMPLE 21-3: ADDRESS MASKING EXAMPLES IN 7-BIT MASKING MODE
Note: The two Most Significant bits of the
address are not affected by address
masking.
7-Bit Addressing:
SSPxADD<7:1> = 1010 000
SSPxMSK<7:1> = 1111 001
Addresses Acknowledged = ACh, A8h, A4h, A0h
10-Bit Addressing :
SSPxADD<7:0> = 1010 0000 (The two MSb are ignored in this example since they are not affected)
SSPxMSK<5:1> = 1111 0011
Addresses Acknowledged = ACh, A8h, A4h, A0h
2011 Microchip Technology Inc. DS39960C-page 299
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21.4.3.5 Reception
When the R/W bit of the address byte is clear and an
address match occurs, the R/W bit of the SSPxSTAT
register is cleared. The received address is loaded into
the SSPxBUF register and the SDAx line is held low
(ACK).
When the address byte overflow condition exists, then
the no Acknowledge (ACK) pulse is given. An overflow
condition is defined as either bit, BF (SSPxSTAT<0>),
is set or bit, SSPOV (SSPxCON1<6>), is set.
An MSSP interrupt is generated for each data transfer
byte. The interrupt flag bit, SSPxIF, must be cleared in
software. The SSPxSTAT register is used to determine
the status of the byte.
If SEN is enabled (SSPxCON2<0> = 1), SCLx will be
held low (clock stretch) following each data transfer. The
clock must be released by setting bit, CKP
(SSPxCON1<4>). See Section 21.4.4 “Clock
Stretching” for more details.
21.4.3.6 Transmission
When the R/W bit of the incoming address byte is set
and an address match occurs, the R/W bit of the
SSPxSTAT register is set. The received address is
loaded into the SSPxBUF register. The ACK pulse will
be sent on the ninth bit and pin SCLx is held low regard-
less of SEN (see Section 21.4.4 “Clock Stretching”
for more details). By stretching the clock, the master
will be unable to assert another clock pulse until the
slave is done preparing the transmit data. The transmit
data must be loaded into the SSPxBUF register which
also loads the SSPxSR register. Then, pin SCLx should
be enabled by setting bit, CKP (SSPxCON1<4>). The
eight data bits are shifted out on the falling edge of the
SCLx input. This ensures that the SDAx signal is valid
during the SCLx high time (Figure 21-10).
The ACK pulse from the master-receiver is latched on
the rising edge of the ninth SCLx input pulse. If the
SDAx line is high (not ACK), then the data transfer is
complete. In this case, when the ACK is latched by the
slave, the slave logic is reset and the slave monitors for
another occurrence of the Start bit. If the SDAx line was
low (ACK), the next transmit data must be loaded into
the SSPxBUF register. Again, pin SCLx must be
enabled by setting bit, CKP.
An MSSP interrupt is generated for each data transfer
byte. The SSPxIF bit must be cleared in software and
the SSPxSTAT register is used to determine the status
of the byte. The SSPxIF bit is set on the falling edge of
the ninth clock pulse.
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DS39960C-page 300 2011 Microchip Technology Inc.
FIGURE 21-8: I2C™ SLAVE MODE TIMING WITH SEN = 0 (RECEPTION, 7-BIT ADDRESS)
SDAx
SCLx
SSPxIF (PIR1<3> or PIR3<7>)
BF (SSPxSTAT<0>)
SSPOV (SSPxCON1<6>)
S1 234 567 89 1 2 345 67 89 1 2345 7 89 P
A7 A6 A5 A4 A3 A2 A1 D7 D6 D5 D4 D3 D2 D1 D0 D7 D6 D5 D4 D3 D1 D0
ACK
Receiving Data
ACK
Receiving Data
R/W = 0
ACK
Receiving Address
Cleared in software
SSPxBUF is read
Bus master
terminates
transfer
SSPOV is set
because SSPxBUF is
still full. ACK is not sent.
D2
6
CKP (SSPxCON<4>)
(CKP does not reset to ‘0’ when SEN = 0)
2011 Microchip Technology Inc. DS39960C-page 301
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FIGURE 21-9: I2C™ SLAVE MODE TIMING WITH SEN = 0 AND ADMSK<5:1> = 01011
(RECEPTION, 7-BIT ADDRESS)
SDAx
SCLx
SSPxIF (PIR1<3> or PIR3<7>)
BF (SSPxSTAT<0>)
SSPOV (SSPxCON1<6>)
S12345678912345678912345 789 P
A7 A6 A5 X A3 X X D7D6 D5D4D3D2D1 D0 D7D6D5D4D3 D1D0
ACK
Receiving Data
ACK
Receiving Data
R/W = 0
ACK
Receiving Address
Cleared in software
SSPxBUF is read
Bus master
terminates
transfer
SSPOV is set
because SSPxBUF is
still full. ACK is not sent.
D2
6
CKP (SSPxCON<4>)
(CKP does not reset to ‘0’ when SEN = 0)
Note 1: x = Don’t care (i.e., address bit can either be a ‘1’ or a ‘0’).
2: In this example, an address equal to A7.A6.A5.X.A3.X.X will be Acknowledged and cause an interrupt.
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FIGURE 21-10 : I 2C™ SLAVE MODE TIMING (TRANSMISSION, 7-BIT ADDRESS)
SDAx
SCLx
BF (SSPxSTAT<0>)
A6 A5 A4 A3 A2 A1 D6 D5 D4 D3 D2 D1 D0
1 2 3 4 5 6 7 8 2 3 4 5 6 7 8 9
SSPxBUF is written in software
Cleared in software
Data in
sampled
S
ACK
Transmitting Data
R/W = 1
ACK
Receiving Address
A7 D7
9 1
D6 D5 D4 D3 D2 D1 D0
2 3 4 5 6 7 8 9
SSPxBUF is written in software
Cleared in software
From SSPxIF ISR
Transmitting Data
D7
1
CKP (SSPxCON<4>)
P
ACK
CKP is set in software CKP is set in software
SCLx held low
while CPU
responds to SSPxIF
SSPxIF (PIR1<3> or PIR3<7>)
From SSPxIF ISR
Clear by reading
2011 Microchip Technology Inc. DS39960C-page 303
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FIGURE 21-11: I2C™ SLAV E MODE TIMING WITH SEN = 0 AND ADMSK<5:1> = 01001
(RECEPTION, 10-BIT ADDRESS)
SDAx
SCLx
SSPxIF (PIR1<3> or PIR3<7>)
BF (SSPxSTAT<0>)
S123456789 123456789 12345 789 P
1 1 1 1 0 A9 A8 A7 A6 A5 X A3 A2 X X D7 D6 D5 D4 D3 D1 D0
Receive Data Byte
ACK
R/W = 0
ACK
Receive First Byte of Address
Cleared in software
D2
6
Cleared in software
Receive Second Byte of Address
Cleared by hardware
when SSPxADD is updated
with low byte of address
UA (SSPxSTAT<1>)
Clock is held low until
update of SSPxADD has
taken place
UA is set indicating that
the SSPxADD needs to be
updated
UA is set indicating that
SSPxADD needs to be
updated
Cleared by hardware when
SSPxADD is updated with high
byte of address
SSPxBUF is written with
contents of SSPxSR
Dummy read of SSPxBUF
to clear BF flag
ACK
CKP (SSPxCON<4>)
12345 789
D7 D6 D5 D4 D3 D1 D0
Receive Data Byte
Bus master
terminates
transfer
D2
6
ACK
Cleared in software Cleared in software
SSPOV (SSPxCON1<6>)
SSPOV is set
because SSPxBUF is
still full. ACK is not sent.
(CKP does not reset to ‘0’ when SEN = 0)
Clock is held low until
update of SSPxADD has
taken place
Note 1: x = Don’t care (i.e., address bit can either be a ‘1’ or a ‘0’).
2: In this example, an address equal to A9.A8.A7.A6.A5.X.A3.A2.X.X will be Acknowledged and cause an interrupt.
3: Note that the Most Significant bits of the address are not affected by the bit masking.
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FIGURE 21-12 : I 2C™ SLAVE MO DE TIMING WITH SEN = 0 (RECEPTION, 10-BIT ADDRESS)
SDAx
SCLx
SSPxIF (PIR1<3> or PIR3<7>)
BF (SSPxSTAT<0>)
S123456789 123456789 12345 789 P
1 1 1 1 0 A9A8 A7 A6A5 A4A3A2A1 A0 D7 D6D5D4D3 D1D0
Receive Data Byte
ACK
R/W = 0
ACK
Receive First Byte of Address
Cleared in software
D2
6
Cleared in software
Receive Second Byte of Address
Cleared by hardware
when SSPxADD is updated
with low byte of address
UA (SSPxSTAT<1>)
Clock is held low until
update of SSPxADD has
taken place
UA is set indicating that
the SSPxADD needs to be
updated
UA is set indicating that
SSPxADD needs to be
updated
Cleared by hardware when
SSPxADD is updated with high
byte of address
SSPxBUF is written with
contents of SSPxSR
Dummy read of SSPxBUF
to clear BF flag
ACK
CKP (SSPxCON<4>)
12345 789
D7 D6 D5 D4 D3 D1 D0
Receive Data Byte
Bus master
terminates
transfer
D2
6
ACK
Cleared in software Cleared in software
SSPOV (SSPxCON1<6>)
SSPOV is set
because SSPxBUF is
still full. ACK is not sent.
(CKP does not reset to ‘0’ when SEN = 0)
Clock is held low until
update of SSPxADD has
taken place
2011 Microchip Technology Inc. DS39960C-page 305
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FIGURE 21-13 : I 2C™ SLAVE MODE TIMING (TRANSMISSION, 10-BIT ADDRESS)
SDAx
SCLx
SSPxIF (PIR1<3> or PIR3<7>)
BF (SSPxSTAT<0>)
S1234 5 6789 12345 678 9 12345 7 89 P
1 1 1 1 0 A9A8 A7 A6A5A4A3A2A1 A0 1 1 1 1 0 A8
R/W = 1
ACK
ACK
R/W = 0
ACK
Receive First Byte of Address
Cleared in software
Bus master
terminates
transfer
A9
6
Receive Second Byte of Address
Cleared by hardware when
SSPxADD is updated with low
byte of address
UA (SSPxSTAT<1>)
Clock is held low until
update of SSPxADD has
taken place
UA is set indicating that
the SSPxADD needs to be
updated
UA is set indicating that
SSPxADD needs to be
updated
Cleared by hardware when
SSPxADD is updated with high
byte of address.
SSPxBUF is written with
contents of SSPxSR
Dummy read of SSPxBUF
to clear BF flag
Receive First Byte of Address
12345 789
D7 D6 D5 D4 D3 D1
ACK
D2
6
Transmitting Data Byte
D0
Dummy read of SSPxBUF
to clear BF flag
Sr
Cleared in software
Write of SSPxBUF
initiates transmit
Cleared in software
Completion of
clears BF flag
CKP (SSPxCON1<4>)
CKP is set in software
CKP is automatically cleared in hardware, holding SCLx low
Clock is held low until
update of SSPxADD has
taken place
data transmission
Clock is held low until
CKP is set to ‘1’
third address sequence
BF flag is clear
at the end of the
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21.4.4 CLOCK STRETCHING
Both 7-Bit and 10-Bit Slave modes implement
automatic clock stretching during a transmit sequence.
The SEN bit (SSPxCON2<0>) allows clock stretching
to be enabled during receives. Setting SEN will cause
the SCLx pin to be held low at the end of each data
receive sequence.
21.4.4.1 Clock Stretching for 7-Bit Slave
Receive Mode (SEN = 1)
In 7-Bit Slave Receive mode, on the falling edge of the
ninth clock at the end of the ACK sequence, if the BF
bit is set, the CKP bit in the SSPxCON1 register is
automatically cleared, forcing the SCLx output to be
held low. The CKP bit being cleared to ‘0’ will assert
the SCLx line low. The CKP bit must be set in the
user’s ISR before reception is allowed to continue. By
holding the SCLx line low, the user has time to service
the ISR and read the contents of the SSPxBUF before
the master device can initiate another receive
sequence. This will prevent buffer overruns from
occurring (see Figure 21-15).
21.4.4.2 Clock Stretching for 10-Bit Slave
Receive Mode (SEN = 1)
In 10-Bit Slave Receive mode, during the address
sequence, clock stretching automatically takes place
but CKP is not cleared. During this time, if the UA bit is
set after the ninth clock, clock stretching is initiated.
The UA bit is set after receiving the upper byte of the
10-bit address and following the receive of the second
byte of the 10-bit address with the R/W bit cleared to
‘0’. The release of the clock line occurs upon updating
SSPxADD. Clock stretching will occur on each data
receive sequence as described in 7-bit mode.
21.4.4.3 Clock Stretching for 7-Bit Slave
Transmit Mode
The 7-Bit Slave Transmit mode implements clock
stretching by clearing the CKP bit after the falling edge
of the ninth clock if the BF bit is clear. This occurs
regardless of the state of the SEN bit.
The user’s ISR must set the CKP bit before transmis-
sion is allowed to continue. By holding the SCLx line
low, the user has time to service the ISR and load the
contents of the SSPxBUF before the master device
can initiate another transmit sequence (see
Figure 21-10).
21.4.4.4 Clock Stretching for 10-Bit Slave
Transmit Mode
In 10-Bit Slave Transmit mode, clock stretching is
controlled during the first two address sequences by
the state of the UA bit, just as it is in 10-Bit Slave
Receive mode. The first two addresses are followed
by a third address sequence, which contains the
high-order bits of the 10-bit address and the R/W bit
set to ‘1’. After the third address sequence is
performed, the UA bit is not set, the module is now
configured in Transmit mode and clock stretching is
controlled by the BF flag as in 7-Bit Slave Transmit
mode (see Figure 21-13).
Note 1: If the user reads the contents of the
SSPxBUF before the falling edge of the
ninth clock, thus clearing the BF bit, the
CKP bit will not be cleared and clock
stretching will not occur.
2: The CKP bit can be set in software
regardless of the state of the BF bit. The
user should be careful to clear the BF bit
in the ISR before the next receive
sequence in order to prevent an overflow
condition.
Note: If the user polls the UA bit and clears it by
updating the SSPxADD register before the
falling edge of the ninth clock occurs, and
if the user hasn’t cleared the BF bit by
reading the SSPxBUF register before that
time, then the CKP bit will still NOT be
asserted low. Clock stretching, on the
basis of the state of the BF bit, only occurs
during a data sequence, not an address
sequence.
Note 1: If the user loads the contents of
SSPxBUF, setting the BF bit before the
falling edge of the ninth clock, the CKP bit
will not be cleared and clock stretching
will not occur.
2: The CKP bit can be set in software
regardless of the state of the BF bit.
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21.4.4.5 Clock Synchronization and
the CKP bit
When the CKP bit is cleared, the SCLx output is forced
to ‘0’. However, clearing the CKP bit will not assert the
SCLx output low until the SCLx output is already
sampled low. Therefore, the CKP bit will not assert the
SCLx line until an external I2C master device has
already asserted the SCLx line. The SCLx output will
remain low until the CKP bit is set and all other
devices on the I2C bus have deasserted SCLx. This
ensures that a write to the CKP bit will not violate the
minimum high time requirement for SCLx (see
Figure 21-14).
FIGURE 21-14: CLOCK SYNCHRONIZATION TIMING
SDAx
SCLx
DX – 1
DX
WR
Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4
SSPxCON1
CKP
Master Device
Deasserts Clock
Master Device
Asserts Clock
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FIGURE 21-15 : I 2C™ SLAVE MODE TIMING WITH SEN = 1 (RECEPTION, 7-BIT ADDRESS)
SDAx
SCLx
SSPxIF (PIR1<3> or PIR3<7>)
BF (SSPxSTAT<0>)
SSPOV (SSPxCON1<6>)
S1 234 56 7 89 1 234 5 67 89 1 23 45 7 89 P
A7 A6 A5 A4 A3 A2 A1 D7 D6 D5 D4 D3 D2 D1 D0 D7 D6 D5 D4 D3 D1 D0
ACK
Receiving Data
ACK
Receiving Data
R/W = 0
ACK
Receiving Address
Cleared in software
SSPxBUF is read
Bus master
terminates
transfer
SSPOV is set
because SSPxBUF is
still full. ACK is not sent.
D2
6
CKP (SSPxCON<4>)
CKP
written
to ‘1’ in
If BF is cleared
prior to the falling
edge of the 9th clock,
CKP will not be reset
to ‘0’ and no clock
stretching will occur
software
Clock is held low until
CKP is set to ‘1’
Clock is not held low
because buffer full bit is
clear prior to falling edge
of 9th clock
Clock is not held low
because ACK =
1
BF is set after falling
edge of the 9th clock,
CKP is reset to ‘0’ and
clock stretching occurs
2011 Microchip Technology Inc. DS39960C-page 309
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FIGURE 21-16 : I 2C™ SLAVE MO DE TIMING WITH SEN = 1 (RECEPTION, 10-BIT ADDRESS)
SDAx
SCLx
SSPxIF (PIR1<3> or PIR3<7>)
BF (SSPxSTAT<0>)
S123456789 123456789 12345 789 P
1 1 1 1 0 A9A8 A7 A6A5A4A3A2A1 A0 D7D6D5D4D3 D1D0
Receive Data Byte
ACK
R/W = 0
ACK
Receive First Byte of Address
Cleared in software
D2
6
Cleared in software
Receive Second Byte of Address
Cleared by hardware when
SSPxADD is updated with low
byte of address after falling edge
UA (SSPxSTAT<1>)
Clock is held low until
update of SSPxADD has
taken place
UA is set indicating that
the SSPxADD needs to be
updated
UA is set indicating that
SSPxADD needs to be
updated
Cleared by hardware when
SSPxADD is updated with high
byte of address after falling edge
SSPxBUF is written with
contents of SSPxSR Dummy read of SSPxBUF
to clear BF flag
ACK
CKP (SSPxCON<4>)
12345 789
D7 D6 D5 D4 D3 D1 D0
Receive Data Byte
Bus master
terminates
transfer
D2
6
ACK
Cleared in software Cleared in software
SSPOV (SSPxCON1<6>)
CKP written to
‘
1
’
Note: An update of the SSPxADD register before
the falling edge of the ninth clock will have no
effect on UA and UA will remain set.
Note: An update of the SSPxADD
register before the falling
edge of the ninth clock will
have no effect on UA and
UA will remain set.
in software
Clock is held low until
update of SSPxADD has
taken place
of ninth clock
of ninth clock
SSPOV is set
because SSPxBUF is
still full. ACK is not sent.
Dummy read of SSPxBUF
to clear BF flag
Clock is held low until
CKP is set to
‘
1
’
Clock is not held low
because ACK =
1
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21.4.5 GENERAL CALL ADDRESS
SUPPORT
The addressing procedure for the I2C bus is such that
the first byte after the Start condition usually
determines which device will be the slave addressed by
the master. The exception is the general call address
which can address all devices. When this address is
used, all devices should, in theory, respond with an
Acknowledge.
The general call address is one of eight addresses
reserved for specific purposes by the I2C protocol. It
consists of all ‘0’s with R/W = 0.
The general call address is recognized when the
General Call Enable bit, GCEN, is enabled
(SSPxCON2<7> set). Following a Start bit detect, eight
bits are shifted into the SSPxSR and the address is
compared against the SSPxADD. It is also compared to
the general call address and fixed in hardware.
If the general call address matches, the SSPxSR is
transferred to the SSPxBUF, the BF flag bit is set
(eighth bit), and on the falling edge of the ninth bit (ACK
bit), the SSPxIF interrupt flag bit is set.
When the interrupt is serviced, the source for the
interrupt can be checked by reading the contents of the
SSPxBUF. The value can be used to determine if the
address was device-specific or a general call address.
In 10-Bit Addressing mode, the SSPxADD is required
to be updated for the second half of the address to
match and the UA bit is set (SSPxSTAT<1>). If the gen-
eral call address is sampled when the GCEN bit is set,
while the slave is configured in 10-Bit Addressing
mode, then the second half of the address is not
necessary, the UA bit will not be set and the slave will
begin receiving data after the Acknowledge
(Figure 21-17).
FIGURE 21-17: SLAVE MODE GENERAL CALL ADDRESS SEQUENCE
(7 OR 10-BIT ADDRESSING MODE)
SDAx
SCLx
S
SSPxIF
BF (SSPxSTAT<0>)
SSPOV (SSPxCON1<6>)
Cleared in Software
SSPxBUF is Read
R/W = 0
ACK
General Call Address
Address is Compared to General Call Address
GCEN (SSPxCON2<7>)
Receiving Data ACK
123456789123456789
D7 D6 D5 D4 D3 D2 D1 D0
after ACK, set Interrupt
‘0’
‘1’
2011 Microchip Technology Inc. DS39960C-page 311
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21.4.6 MASTER MODE
Master mode is enabled by setting and clearing the
appropriate SSPM bits in SSPxCON1, and by setting
the SSPEN bit. In Master mode, the SCLx and SDAx
lines are manipulated by the MSSP hardware if the
TRIS bits are set.
The Master mode of operation is supported by interrupt
generation on the detection of the Start and Stop
conditions. The Stop (P) and Start (S) bits are cleared
from a Reset or when the MSSP module is disabled.
Control of the I2C bus may be taken when the P bit is
set, or the bus is Idle, with both the S and P bits clear.
In Firmware Controlled Master mode, user code
conducts all I2C bus operations based on Start and
Stop bit conditions.
Once Master mode is enabled, the user has six
options.
1. Assert a Start condition on SDAx and SCLx.
2. Assert a Repeated Start condition on SDAx and
SCLx.
3. Write to the SSPxBUF register initiating
transmission of data/address.
4. Configure the I2C port to receive data.
5. Generate an Acknowledge condition at the end
of a received byte of data.
6. Generate a Stop condition on SDAx and SCLx.
The following events will cause the MSSP Interrupt
Flag bit, SSPxIF, to be set (and MSSP interrupt, if
enabled):
• Start condition
• Stop condition
• Data transfer byte transmitted/received
• Acknowledge transmitted
• Repeated Start
FIGURE 21-18: MSSP BLOCK DIAGRAM (I2C™ MASTER MODE)
Note: The MSSP module, when configured in
I2C Master mode, does not allow queueing
of events. For instance, the user is not
allowed to initiate a Start condition and
immediately write the SSPxBUF register
to initiate transmission before the Start
condition is complete. In this case, the
SSPxBUF will not be written to and the
WCOL bit will be set, indicating that a write
to the SSPxBUF did not occur.
Read Write
SSPxSR
Start bit, Stop bit,
SSPxBUF
Internal
Data Bus
Set/Reset S, P (SSPxSTAT), WCOL (SSPxCON1);
Shift
Clock
MSb LSb
SDAx
Acknowledge
Generate
Stop bit Detect
Write Collision Detect
Clock Arbitration
State Counter for
End of XMIT/RCV
SCLx
SCLx In
Bus Collision
SDAx In
Receive Enable
Clock Cntl
Clock Arbitrate/WCOL Detect
(hold off clock source)
SSPxADD<6:0>
Baud
Set SSPxIF, BCLxIF;
Reset ACKSTAT, PEN (SSPxCON2)
Rate
Generator
SSPM<3:0>
Start bit Detect
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21.4.6.1 I2C™ Master Mode Operation
The master device generates all of the serial clock
pulses and the Start and Stop conditions. A transfer is
ended with a Stop condition or with a Repeated Start
condition. Since the Repeated Start condition is also
the beginning of the next serial transfer, the I2C bus will
not be released.
In Master Transmitter mode, serial data is output
through SDAx while SCLx outputs the serial clock. The
first byte transmitted contains the slave address of the
receiving device (7 bits) and the Read/Write (R/W) bit.
In this case, the R/W bit will be logic ‘0’. Serial data is
transmitted 8 bits at a time. After each byte is transmit-
ted, an Acknowledge bit is received. Start and Stop
conditions are output to indicate the beginning and the
end of a serial transfer.
In Master Receive mode, the first byte transmitted
contains the slave address of the transmitting device
(7 bits) and the R/W bit. In this case, the R/W bit will be
logic ‘1’. Thus, the first byte transmitted is a 7-bit slave
address, followed by a ‘1’ to indicate the receive bit.
Serial data is received via SDAx, while SCLx outputs
the serial clock. Serial data is received 8 bits at a time.
After each byte is received, an Acknowledge bit is
transmitted. Start and Stop conditions indicate the
beginning and end of transmission.
The Baud Rate Generator, used for the SPI mode
operation, is used to set the SCLx clock frequency for
either 100 kHz, 400 kHz or 1 MHz I2C operation. See
Section 21.4.7 “Baud Rate” for more details.
A typical transmit sequence would go as follows:
1. The user generates a Start condition by setting
the Start Enable bit, SEN (SSPxCON2<0>).
2. SSPxIF is set. The MSSP module will wait the
required start time before any other operation
takes place.
3. The user loads the SSPxBUF with the slave
address to transmit.
4. Address is shifted out the SDAx pin until all 8 bits
are transmitted.
5. The MSSP module shifts in the ACK bit from the
slave device and writes its value into the
SSPxCON2 register (SSPxCON2<6>).
6. The MSSP module generates an interrupt at the
end of the ninth clock cycle by setting the
SSPxIF bit.
7. The user loads the SSPxBUF with eight bits of
data.
8. Data is shifted out the SDAx pin until all 8 bits
are transmitted.
9. The MSSP module shifts in the ACK bit from the
slave device and writes its value into the
SSPxCON2 register (SSPxCON2<6>).
10. The MSSP module generates an interrupt at the
end of the ninth clock cycle by setting the
SSPxIF bit.
11. The user generates a Stop condition by setting
the Stop Enable bit, PEN (SSPxCON2<2>).
12. Interrupt is generated once the Stop condition is
complete.
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21.4.7 BAUD RATE
In I2C Master mode, the Baud Rate Generator (BRG)
reload value is placed in the lower 7 bits of the
SSPxADD register (Figure 21-19). When a write
occurs to SSPxBUF, the Baud Rate Generator will
automatically begin counting. The BRG counts down to
0 and stops until another reload has taken place. The
BRG count is decremented twice per instruction cycle
(T
CY) on the Q2 and Q4 clocks. In I2C Master mode, the
BRG is reloaded automatically.
Once the given operation is complete (i.e., transmis-
sion of the last data bit is followed by ACK), the internal
clock will automatically stop counting and the SCLx pin
will remain in its last state.
Table 21-3 demonstrates clock rates based on
instruction cycles and the BRG value loaded into
SSPxADD. The SSPxADD BRG value of 0x00 is not
supported.
21.4.7.1 Baud Rate and Module
Interdependence
Because MSSP1 and MSSP2 are independent, they
can operate simultaneously in I2C Master mode at
different baud rates. This is done by using different
BRG reload values for each module.
Because this mode derives its basic clock source from
the system clock, any changes to the clock will affect
both modules in the same proportion. It may be
possible to change one or both baud rates back to a
previous value by changing the BRG reload value.
FIGURE 21-19: BAUD RATE GENERATOR BLOCK DIAGRAM
TABLE 21-3: I2C™ CLOCK RATE w/BRG
FOSC FCY FCY * 2 BRG Value FSCL
(2 Rollovers of BRG)
40 MHz 10 MHz 20 MHz 18h 400 kHz(1)
40 MHz 10 MHz 20 MHz 1Fh 312.5 kHz
40 MHz 10 MHz 20 MHz 63h 100 kHz
16 MHz 4 MHz 8 MHz 09h 400 kHz(1)
16 MHz 4 MHz 8 MHz 0Ch 308 kHz
16 MHz 4 MHz 8 MHz 27h 100 kHz
4 MHz 1 MHz 2 MHz 02h 333 kHz(1)
4 MHz 1 MHz 2 MHz 09h 100 kHz
16 MHz 4 MHz 8 MHz 03h 1 MHz(1,2)
Note 1: The I2C interface does not conform to the 400 kHz I2C specification (which applies to rates greater than
100 kHz) in all details, but may be used with care where higher rates are required by the application.
2: A minimum of 16 MHz FOSC is required to get 1 MHz I2C.
SSPM<3:0>
BRG Down Counter
CLKO FOSC/4
SSPxADD<6:0>
SSPM<3:0>
SCLx
Reload
Control
Reload
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21.4.7.2 Clock Arbitration
Clock arbitration occurs when the master, during any
receive, transmit or Repeated Start/Stop condition,
deasserts the SCLx pin (SCLx allowed to float high).
When the SCLx pin is allowed to float high, the Baud
Rate Generator (BRG) is suspended from counting
until the SCLx pin is actually sampled high. When the
SCLx pin is sampled high, the Baud Rate Generator is
reloaded with the contents of SSPxADD<6:0> and
begins counting. This ensures that the SCLx high time
will always be at least one BRG rollover count in the
event that the clock is held low by an external device
(Figure 21-20).
FIGURE 21-20: BAUD RATE GENERATOR TIMING WITH CLOCK ARBITRATION
SDAx
SCLx
SCLx Deasserted but Slave Holds
DX – 1DX
BRG
SCLx is Sampled High, Reload takes
place and BRG Starts its Count
03h 02h 01h 00h (hold off) 03h 02h
Reload
BRG
Value
SCLx Low (clock arbitration)
SCLx Allowed to Transition High
BRG Decrements on
Q2 and Q4 Cycles
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21.4.8 I2C™ MASTER MODE START
CONDITION TIMING
To initiate a Start condition, the user sets the Start
Enable bit, SEN (SSPxCON2<0>). If the SDAx and
SCLx pins are sampled high, the Baud Rate Generator
is reloaded with the contents of SSPxADD<6:0> and
starts its count. If SCLx and SDAx are both sampled
high when the Baud Rate Generator times out (TBRG),
the SDAx pin is driven low. The action of the SDAx
being driven low while SCLx is high is the Start condi-
tion and causes the S bit (SSPxSTAT<3>) to be set.
Following this, the Baud Rate Generator is reloaded
with the contents of SSPxADD<6:0> and resumes its
count. When the Baud Rate Generator times out
(TBRG), the SEN bit (SSPxCON2<0>) will be
automatically cleared by hardware. The Baud Rate
Generator is suspended, leaving the SDAx line held low
and the Start condition is complete.
21.4.8.1 WCOL Status Flag
If the user writes the SSPxBUF when a Start sequence
is in progress, the WCOL bit is set and the contents of
the buffer are unchanged (the write doesn’t occur).
FIGURE 21-21: FIRST START BIT TIMING
Note: If, at the beginning of the Start condition,
the SDAx and SCLx pins are already
sampled low or if during the Start condi-
tion, the SCLx line is sampled low before
the SDAx line is driven low, a bus collision
occurs, the Bus Collision Interrupt Flag,
BCLxIF, is set, the Start condition is
aborted and the I2C module is reset into its
Idle state.
Note: Because queueing of events is not
allowed, writing to the lower 5 bits of
SSPxCON2 is disabled until the Start
condition is complete.
SDAx
SCLx
S
TBRG
1st bit 2nd bit
TBRG
SDAx = 1, At Completion of Start bit,
SCLx = 1
Write to SSPxBUF Occurs Here
TBRG
Hardware Clears SEN bit
TBRG
Write to SEN bit Occurs Here Set S bit (SSPxSTAT<3>)
and Sets SSPxIF bit
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21.4.9 I2C™ MASTER MODE REPEATED
START CONDITION TIMING
A Repeated Start condition occurs when the RSEN bit
(SSPxCON2<1>) is programmed high and the I2C logic
module is in the Idle state. When the RSEN bit is set,
the SCLx pin is asserted low. When the SCLx pin is
sampled low, the Baud Rate Generator is loaded with
the contents of SSPxADD<5:0> and begins counting.
The SDAx pin is released (brought high) for one Baud
Rate Generator count (TBRG). When the Baud Rate
Generator times out, and if SDAx is sampled high, the
SCLx pin will be deasserted (brought high). When
SCLx is sampled high, the Baud Rate Generator is
reloaded with the contents of SSPxADD<6:0> and
begins counting. SDAx and SCLx must be sampled
high for one TBRG. This action is then followed by
assertion of the SDAx pin (SDAx = 0) for one TBRG
while SCLx is high. Following this, the RSEN bit
(SSPxCON2<1>) will be automatically cleared and the
Baud Rate Generator will not be reloaded, leaving the
SDAx pin held low. As soon as a Start condition is
detected on the SDAx and SCLx pins, the S bit
(SSPxSTAT<3>) will be set. The SSPxIF bit will not be
set until the Baud Rate Generator has timed out.
Immediately following the SSPxIF bit getting set, the
user may write the SSPxBUF with the 7-bit address in
7-bit mode or the default first address in 10-bit mode.
After the first eight bits are transmitted and an ACK is
received, the user may then transmit an additional eight
bits of address (10-bit mode) or eight bits of data (7-bit
mode).
21.4.9.1 WCOL Status Flag
If the user writes the SSPxBUF when a Repeated Start
sequence is in progress, the WCOL is set and the
contents of the buffer are unchanged (the write doesn’t
occur).
FIGURE 21-22: REPEATED START CONDITION WAVEFORM
Note 1: If RSEN is programmed while any other
event is in progress, it will not take effect.
2: A bus collision during the Repeated Start
condition occurs if:
• SDAx is sampled low when SCLx
goes from low-to-high.
• SCLx goes low before SDAx is
asserted low. This may indicate that
another master is attempting to
transmit a data ‘1’.
Note: Because queueing of events is not
allowed, writing of the lower 5 bits of
SSPxCON2 is disabled until the Repeated
Start condition is complete.
SDAx
SCLx
Sr = Repeated Start
Write to SSPxCON2 Occurs Here:
Write to SSPxBUF Occurs Here
on Falling Edge of Ninth Clock,
End of XMIT
At Completion of Start bit,
Hardware Clears RSEN bit
1st bit
S bit Set by Hardware
TBRG
SDAx = 1,
SDAx = 1,
SCLx (no change).
SCLx = 1
and Sets SSPxIF
RSEN bit Set by Hardware
TBRG
TBRG TBRG TBRG
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21.4.10 I2C™ MASTER MODE
TRANSMISSION
Transmission of a data byte, a 7-bit address or the
other half of a 10-bit address, is accomplished by
simply writing a value to the SSPxBUF register. This
action will set the Buffer Full flag bit, BF, and allow the
Baud Rate Generator to begin counting and start the
next transmission. Each bit of address/data will be
shifted out onto the SDAx pin after the falling edge of
SCLx is asserted (see data hold time specification
Parameter 106). SCLx is held low for one Baud Rate
Generator rollover count (TBRG). Data should be valid
before SCLx is released high (see data setup time
specification Parameter 107). When the SCLx pin is
released high, it is held that way for TBRG. The data on
the SDAx pin must remain stable for that duration and
some hold time after the next falling edge of SCLx.
After the eighth bit is shifted out (the falling edge of the
eighth clock), the BF flag is cleared and the master
releases SDAx. This allows the slave device being
addressed to respond with an ACK bit during the ninth
bit time if an address match occurred, or if data was
received properly. The status of ACK is written into the
ACKDT bit on the falling edge of the ninth clock. If the
master receives an Acknowledge, the Acknowledge
Status bit, ACKSTAT, is cleared; if not, the bit is set.
After the ninth clock, the SSPxIF bit is set and the
master clock (Baud Rate Generator) is suspended until
the next data byte is loaded into the SSPxBUF, leaving
SCLx low and SDAx unchanged (Figure 21-23).
After the write to the SSPxBUF, each bit of the address
will be shifted out on the falling edge of SCLx until all
seven address bits and the R/W bit are completed. On
the falling edge of the eighth clock, the master will
deassert the SDAx pin, allowing the slave to respond
with an Acknowledge. On the falling edge of the ninth
clock, the master will sample the SDAx pin to see if the
address was recognized by a slave. The status of the
ACK bit is loaded into the ACKSTAT status bit
(SSPxCON2<6>). Following the falling edge of the
ninth clock transmission of the address, the SSPxIF
flag is set, the BF flag is cleared and the Baud Rate
Generator is turned off until another write to the
SSPxBUF takes place, holding SCLx low and allowing
SDAx to float.
21.4.10.1 BF Status Flag
In Transmit mode, the BF bit (SSPxSTAT<0>) is set
when the CPU writes to SSPxBUF and is cleared when
all 8 bits are shifted out.
21.4.10.2 WCOL Status Flag
If the user writes the SSPxBUF when a transmit is
already in progress (i.e., SSPxSR is still shifting out a
data byte), the WCOL bit is set and the contents of the
buffer are unchanged (the write doesn’t occur) after
2T
CY after the SSPxBUF write. If SSPxBUF is rewritten
within 2 TCY, the WCOL bit is set and SSPxBUF is
updated. This may result in a corrupted transfer.
The user should verify that the WCOL bit is clear after
each write to SSPxBUF to ensure the transfer is correct.
In all cases, WCOL must be cleared in software.
21.4.10.3 ACKSTAT Status Flag
In Transmit mode, the ACKSTAT bit (SSPxCON2<6>)
is cleared when the slave has sent an Acknowledge
(ACK =0) and is set when the slave does not Acknowl-
edge (ACK = 1). A slave sends an Acknowledge when
it has recognized its address (including a general call),
or when the slave has properly received its data.
21.4.11 I2C™ MASTER MODE RECEPTION
Master mode reception is enabled by programming the
Receive Enable bit, RCEN (SSPxCON2<3>).
The Baud Rate Generator begins counting, and on
each rollover, the state of the SCLx pin changes
(high-to-low/low-to-high) and data is shifted into the
SSPxSR. After the falling edge of the eighth clock, the
receive enable flag is automatically cleared, the con-
tents of the SSPxSR are loaded into the SSPxBUF, the
BF flag bit is set, the SSPxIF flag bit is set and the Baud
Rate Generator is suspended from counting, holding
SCLx low. The MSSP is now in Idle state awaiting the
next command. When the buffer is read by the CPU,
the BF flag bit is automatically cleared. The user can
then send an Acknowledge bit at the end of reception
by setting the Acknowledge Sequence Enable bit,
ACKEN (SSPxCON2<4>).
21.4.11.1 BF Status Flag
In receive operation, the BF bit is set when an address
or data byte is loaded into SSPxBUF from SSPxSR. It
is cleared when the SSPxBUF register is read.
21.4.11.2 SSPOV Status Flag
In receive operation, the SSPOV bit is set when 8 bits
are received into the SSPxSR and the BF flag bit is
already set from a previous reception.
21.4.11.3 WCOL Status Flag
If the user writes the SSPxBUF when a receive is
already in progress (i.e., SSPxSR is still shifting in a
data byte), the WCOL bit is set and the contents of the
buffer are unchanged (the write doesn’t occur).
Note: The MSSP module must be in an inactive
state before the RCEN bit is set or the
RCEN bit will be disregarded.
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FIGURE 21-23 : I2C™ MASTER MODE WAVEFORM (T RANSMISSION, 7 OR 10-BIT ADDRESS)
SDAx
SCLx
SSPxIF
BF (SSPxSTAT<0>)
SEN
A7 A6 A5 A4 A3 A2 A1 ACK = 0D7 D6 D5 D4 D3 D2 D1 D0
ACK
Transmitting Data or Second Half
R/W = 0Transmit Address to Slave
123456789 123456789 P
Cleared in software service routine
SSPxBUF is written in software
from MSSP interrupt
After Start condition, SEN cleared by hardware
S
SSPxBUF written with 7-bit address and R/W,
start transmit
SCLx held low
while CPU
responds to SSPxIF
SEN = 0
of 10-bit Address
Write SSPxCON2<0> (SEN = 1),
Start condition begins From slave, clear ACKSTAT bit (SSPxCON2<6>)
ACKSTAT in
SSPxCON2 = 1
Cleared in software
SSPxBUF written
PEN
R/W
Cleared in software
2011 Microchip Technology Inc. DS39960C-page 319
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FIGURE 21-24 : I2C™ MASTER MODE WAVEFORM (RECEPTION, 7-BIT ADDRESS)
P
9
87
6
5
D0
D1
D2
D3D4
D5
D6D7
S
A7 A6 A5 A4 A3 A2 A1
SDAx
SCLx 12
345678912345678 9 1234
Bus master
terminates
transfer
ACK
Receiving Data from Slave
Receiving Data from Slave
D0
D1
D2
D3D4
D5
D6D7
ACK
R/W = 1
Transmit Address to Slave
SSPxIF
BF
ACK is not sent
Write to SSPxCON2<0> (SEN = 1),
Write to SSPxBUF occurs here, ACK from Slave
Master configured as a receiver
by programming SSPxCON2<3> (RCEN = 1)
PEN bit = 1
written here
Data shifted in on falling edge of CLK
Cleared in software
start XMIT
SEN = 0
SSPOV
SDAx = 0, SCLx = 1,
while CPU
(SSPxSTAT<0>)
ACK
Cleared in software
Cleared in software
Set SSPxIF interrupt
at end of receive
Set P bit
(SSPxSTAT<4>)
and SSPxIF
ACK from master,
Set SSPxIF at end
Set SSPxIF interrupt
at end of Acknowledge
sequence
Set SSPxIF interrupt
at end of Acknowledge
sequence
of receive
Set ACKEN, start Acknowledge sequence,
SDAx = ACKDT = 1
RCEN cleared
automatically
RCEN = 1, start
next receive
Write to SSPxCON2<4>
to start Acknowledge sequence,
SDAx = ACKDT (SSPxCON2<5>) = 0
RCEN cleared
automatically
responds to SSPxIF
ACKEN
begin Start condition
Cleared in software
SDAx = ACKDT = 0
Last bit is shifted into SSPxSR and
contents are unloaded into SSPxBUF
Cleared in
software
SSPOV is set because
SSPxBUF is still full
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21.4.12 ACKNOWLEDGE SEQUENCE
TIMING
An Acknowledge sequence is enabled by setting the
Acknowledge Sequence Enable bit, ACKEN
(SSPxCON2<4>). When this bit is set, the SCLx pin is
pulled low and the contents of the Acknowledge data bit
are presented on the SDAx pin. If the user wishes to gen-
erate an Acknowledge, then the ACKDT bit should be
cleared. If not, the user should set the ACKDT bit before
starting an Acknowledge sequence. The Baud Rate Gen-
erator then counts for one rollover period (TBRG) and the
SCLx pin is deasserted (pulled high). When the SCLx pin
is sampled high (clock arbitration), the Baud Rate Gener-
ator counts for TBRG; the SCLx pin is then pulled low.
Following this, the ACKEN bit is automatically cleared, the
Baud Rate Generator is turned off and the MSSP module
then goes into an inactive state (Figure 21-25).
21.4.12.1 WCOL Status Flag
If the user writes the SSPxBUF when an Acknowledge
sequence is in progress, then WCOL is set and the
contents of the buffer are unchanged (the write doesn’t
occur).
21.4.13 STOP CONDITION TIMING
A Stop bit is asserted on the SDAx pin at the end of a
receive/transmit by setting the Stop Sequence Enable
bit, PEN (SSPxCON2<2>). At the end of a
receive/transmit, the SCLx line is held low after the
falling edge of the ninth clock. When the PEN bit is set,
the master will assert the SDAx line low. When the
SDAx line is sampled low, the Baud Rate Generator is
reloaded and counts down to 0. When the Baud Rate
Generator times out, the SCLx pin will be brought high
and one TBRG (Baud Rate Generator rollover count)
later, the SDAx pin will be deasserted. When the SDAx
pin is sampled high while SCLx is high, the P bit
(SSPxSTAT<4>) is set. A TBRG later, the PEN bit is
cleared and the SSPxIF bit is set (Figure 21-26).
21.4.13.1 WCOL Status Flag
If the user writes the SSPxBUF when a Stop sequence
is in progress, then the WCOL bit is set and the
contents of the buffer are unchanged (the write doesn’t
occur).
FIGURE 21-25: ACKNOWLEDGE SEQUEN CE WAVEFORM
FIGURE 21-26: STOP CONDITION RECEIVE OR TRANSMIT MODE
Note: TBRG = one Baud Rate Generator period.
SDAx
SCLx
SSPxIF Set at
Acknowledge Sequence Starts Here,
Write to SSPxCON2, ACKEN Automatically Cleared
Cleared in
TBRG TBRG
the End of Receive
8
ACKEN = 1, ACKDT = 0
D0
9
SSPxIF
Software SSPxIF Set at the End
of Acknowledge Sequence
Cleared in
Software
ACK
SCLx
SDAx
SDAx Asserted Low Before Rising Edge of Clock
Write to SSPxCON2,
Set PEN
Falling Edge of
SCLx = 1 for TBRG, Followed by SDAx = 1 for TBRG
9th Clock
SCLx Brought High After TBRG
Note: TBRG = one Baud Rate Generator period.
TBRG TBRG
after SDAx Sampled High. P bit (SSPxSTAT<4>) is Set
TBRG
to Set up Stop Condition
ACK
P
TBRG
PEN bit (SSPxCON2<2>) is Cleared by
Hardware and the SSPxIF bit is Set
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21.4.14 SLEEP OPERATION
While in Sleep mode, the I2C module can receive
addresses or data and when an address match or
complete byte transfer occurs, wake the processor
from Sleep (if the MSSP interrupt is enabled).
21.4.15 EFFECTS OF A RESET
A Reset disables the MSSP module and terminates the
current transfer.
21.4.16 MULTI-MASTER MODE
In Multi-Master mode, the interrupt generation on the
detection of the Start and Stop conditions allows the
determination of when the bus is free. The Stop (P) and
Start (S) bits are cleared from a Reset or when the
MSSP module is disabled. Control of the I2C bus may
be taken when the P bit (SSPxSTAT<4>) is set, or the
bus is Idle, with both the S and P bits clear. When the
bus is busy, enabling the MSSP interrupt will generate
the interrupt when the Stop condition occurs.
In multi-master operation, the SDAx line must be
monitored for arbitration to see if the signal level is the
expected output level. This check is performed in
hardware with the result placed in the BCLxIF bit.
The states where arbitration can be lost are:
• Address Transfer
• Data Transfer
• A Start Condition
• A Repeated Start Condition
• An Acknowledge Condition
21.4.17 MULTI -MASTER COMMUNICATION,
BUS COLLISION AND BUS
ARBITRATION
Multi-Master mode support is achieved by bus arbitra-
tion. When the master outputs address/data bits onto
the SDAx pin, arbitration takes place when the master
outputs a ‘1’ on SDAx, by letting SDAx float high, and
another master asserts a ‘0’. When the SCLx pin floats
high, data should be stable. If the expected data on
SDAx is a ‘1’ and the data sampled on the SDAx
pin = 0, then a bus collision has taken place. The
master will set the Bus Collision Interrupt Flag, BCLxIF,
and reset the I2C port to its Idle state (Figure 21-27).
If a transmit was in progress when the bus collision
occurred, the transmission is halted, the BF flag is
cleared, the SDAx and SCLx lines are deasserted and
the SSPxBUF can be written to. When the user services
the bus collision Interrupt Service Routine and if the I2C
bus is free, the user can resume communication by
asserting a Start condition.
If a Start, Repeated Start, Stop or Acknowledge condition
was in progress when the bus collision occurred, the con-
dition is aborted, the SDAx and SCLx lines are
deasserted and the respective control bits in the
SSPxCON2 register are cleared. When the user services
the bus collision Interrupt Service Routine (ISR), and if
the I2C bus is free, the user can resume communication
by asserting a Start condition.
The master will continue to monitor the SDAx and SCLx
pins. If a Stop condition occurs, the SSPxIF bit will be set.
A write to the SSPxBUF will start the transmission of
data at the first data bit regardless of where the
transmitter left off when the bus collision occurred.
In Multi-Master mode, the interrupt generation on the
detection of Start and Stop conditions allows the determi-
nation of when the bus is free. Control of the I2C bus can
be taken when the P bit is set in the SSPxSTAT register,
or the bus is Idle and the S and P bits are cleared.
FIGURE 21-27: BUS COLLISION TIMING FOR TRANSMIT AND ACKNOWLEDGE
SDAx
SCLx
BCLxIF
SDAx Released
SDAx Line Pulled Low
by Another Source
Sample SDAx. While SCLx is High,
Data Doesn’t Match what is Driven
Bus Collision has Occurred
Set Bus Collision
Interrupt (BCLxIF)
by the Master;
by Master
Data Changes
while SCLx = 0
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21.4.17.1 Bus Collision During a Start
Condition
During a Start condition, a bus collision occurs if:
a) SDAx or SCLx is sampled low at the beginning
of the Start condition (Figure 21-28).
b) SCLx is sampled low before SDAx is asserted
low (Figure 21-29).
During a Start condition, both the SDAx and the SCLx
pins are monitored.
If the SDAx pin is already low, or the SCLx pin is
already low, then all of the following occur:
• the Start condition is aborted,
• the BCLxIF flag is set and
• the MSSP module is reset to its inactive state
(Figure 21-28)
The Start condition begins with the SDAx and SCLx
pins deasserted. When the SDAx pin is sampled high,
the Baud Rate Generator is loaded from
SSPxADD<6:0> and counts down to 0. If the SCLx pin
is sampled low while SDAx is high, a bus collision
occurs because it is assumed that another master is
attempting to drive a data ‘1’ during the Start condition.
If the SDAx pin is sampled low during this count, the
BRG is reset and the SDAx line is asserted early
(Figure 21-30). If, however, a ‘1’ is sampled on the
SDAx pin, the SDAx pin is asserted low at the end of
the BRG count. The Baud Rate Generator is then
reloaded and counts down to 0. If the SCLx pin is
sampled as ‘0’ during this time, a bus collision does not
occur. At the end of the BRG count, the SCLx pin is
asserted low.
FIGURE 21-28: BUS COLLISION DURING START CONDITION (SDAx ONLY)
Note: The reason that bus collision is not a fac-
tor during a Start condition is that no two
bus masters can assert a Start condition
at the exact same time. Therefore, one
master will always assert SDAx before the
other. This condition does not cause a bus
collision because the two masters must be
allowed to arbitrate the first address
following the Start condition. If the address
is the same, arbitration must be allowed to
continue into the data portion, Repeated
Start or Stop conditions.
SDAx
SCLx
SEN
SDAx Sampled Low Before
SDAx Goes Low Before the SEN bit is Set.
S bit and SSPxIF Set Because
MSSP module Reset into Idle State
SEN Cleared Automatically Because of Bus Collision,
S bit and SSPxIF Set Because
Set SEN, Enable Start
Condition if SDAx = 1, SCLx = 1
SDAx = 0, SCLx = 1
BCLxIF
S
SSPxIF
SDAx = 0, SCLx = 1
SSPxIF and BCLxIF are
Cleared in Software
SSPxIF and BCLxIF are
Cleared in Software
Set BCLxIF,
Start Condition, Set BCLxIF,
2011 Microchip Technology Inc. DS39960C-page 323
PIC18F87K22 FAMILY
FIGURE 21-29: BUS COLLISION DURING START CONDITION (SCLx = 0)
FIGURE 21-30: BRG RESET DUE TO SDAx ARBITRATION DURING START CONDITION
SDAx
SCLx
SEN Bus Collision Occurs, Set BCLxIF
SCLx = 0 Before SDAx = 0,
Set SEN, Enable Start
Sequence if SDAx = 1, SCLx = 1
TBRG TBRG
SDAx = 0, SCLx = 1
BCLxIF
S
SSPxIF
Interrupt Cleared
in Software
Bus Collision Occurs, Set BCLxIF
SCLx = 0 Before BRG Time-out,
‘0’‘0’
‘0’‘0’
SDAx
SCLx
SEN
Set S
Less than TBRG TBRG
SDAx = 0, SCLx = 1
BCLxIF
S
SSPxIF
S
Interrupts Cleared
in Software
Set SSPxIF
SDAx = 0, SCLx = 1,
SCLx Pulled Low After BRG
Time-out
Set SSPxIF
‘0’
SDAx Pulled Low by Other Master,
Reset BRG and Assert SDAx
Set SEN, Enable Start
Sequence if SDAx = 1, SCLx = 1
PIC18F87K22 FAMILY
DS39960C-page 324 2011 Microchip Technology Inc.
21.4.17.2 Bus Collision During a Repeated
Start Condition
During a Repeated Start condition, a bus collision
occurs if:
a) A low level is sampled on SDAx when SCLx
goes from a low level to a high level.
b) SCLx goes low before SDAx is asserted low,
indicating that another master is attempting to
transmit a data ‘1’.
When the user deasserts SDAx and the pin is allowed
to float high, the BRG is loaded with SSPxADD<6:0>
and counts down to 0. The SCLx pin is then deasserted
and when sampled high, the SDAx pin is sampled.
If SDAx is low, a bus collision has occurred (i.e., another
master is attempting to transmit a data ‘0’,
Figure 21-31). If SDAx is sampled high, the BRG is
reloaded and begins counting. If SDAx goes from
high-to-low before the BRG times out, no bus collision
occurs because no two masters can assert SDAx at
exactly the same time.
If SCLx goes from high-to-low before the BRG times
out and SDAx has not already been asserted, a bus
collision occurs. In this case, another master is
attempting to transmit a data ‘1’ during the Repeated
Start condition (see Figure 21-32).
If, at the end of the BRG time-out, both SCLx and SDAx
are still high, the SDAx pin is driven low and the BRG is
reloaded and begins counting. At the end of the count,
regardless of the status of the SCLx pin, the SCLx pin is
driven low and the Repeated Start condition is complete.
FIGURE 21-31: BUS COLLISION DURING A REPEATED START CONDITION (CASE 1)
FIGURE 21-32: BUS COLLISION DURING REPEATED START CONDITION (CASE 2)
SDAx
SCLx
RSEN
BCLxIF
S
SSPxIF
Sample SDAx when SCLx goes High,
If SDAx = 0, Set BCLxIF and Release SDAx and SCLx
Cleared in Software
‘0’
‘0’
SDAx
SCLx
BCLxIF
RSEN
S
SSPxIF
Interrupt Cleared
in Software
SCLx goes Low Before SDAx,
Set BCLxIF, Release SDAx and SCLx
TBRG TBRG
‘0’
2011 Microchip Technology Inc. DS39960C-page 325
PIC18F87K22 FAMILY
21.4.17.3 Bus Collision During a Stop
Condition
Bus collision occurs during a Stop condition if:
a) After the SDAx pin has been deasserted and
allowed to float high, SDAx is sampled low after
the BRG has timed out.
b) After the SCLx pin is deasserted, SCLx is
sampled low before SDAx goes high.
The Stop condition begins with SDAx asserted low.
When SDAx is sampled low, the SCLx pin is allowed to
float. When the pin is sampled high (clock arbitration),
the Baud Rate Generator is loaded with
SSPxADD<6:0> and counts down to 0. After the BRG
times out, SDAx is sampled. If SDAx is sampled low, a
bus collision has occurred. This is due to another
master attempting to drive a data ‘0’ (Figure 21-33). If
the SCLx pin is sampled low before SDAx is allowed to
float high, a bus collision occurs. This is another case
of another master attempting to drive a data ‘0’
(Figure 21-34).
FIGURE 21-33: BUS COLLISION DURING A STOP CONDITION (CASE 1)
FIGURE 21-34: BUS COLLISION DURING A STOP CONDITION (CASE 2)
SDAx
SCLx
BCLxIF
PEN
P
SSPxIF
TBRG TBRG TBRG
SDAx Asserted Low
SDAx Sampled
Low After TBRG,
Set BCLxIF
‘0’
‘0’
SDAx
SCLx
BCLxIF
PEN
P
SSPxIF
TBRG TBRG TBRG
Assert SDAx SCLx goes Low Before SDAx goes High,
Set BCLxIF
‘0’
‘0’
PIC18F87K22 FAMILY
DS39960C-page 326 2011 Microchip Technology Inc.
TABLE 21-4: REGISTERS ASSOCIATED WITH I2C™ OPERATION
Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
INTCON GIE/GIEH PEIE/GIEL TMR0IE INT0IE RBIE TMR0IF INT0IF RBIF
PIR1 PSPIF ADIF RC1IF TX1IF SSP1IF TMR1GIF TMR2IF TMR1IF
PIE1 PSPIE ADIE RC1IE TX1IE SSP1IE TMR1GIE TMR2IE TMR1IE
IPR1 PSPIP ADIP RC1IP TX1IP SSP1IP TMR1GIP TMR2IP TMR1IP
PIR2 OSCFIF — SSP2IF BLC2IF BCL1IF HLVDIF TMR3IF TMR3GIF
PIE2 OSCFIE — SSP2IE BLC2IE BCL1IE HLVDIE TMR3IE TMR3GIE
IPR2 OSCFIP — SSP2IP BLC2IP BCL1IP HLVDIP TMR3IP TMR3GIP
PIR3 TMR5GIF —RC2IF TX2IF CTMUIF CCP2IF CCP1IF RTCCIF
PIE3 TMR5GIE —RC2IE TX2IE CTMUIE CCP2IE CCP1IE RTCCIE
IPR3 TMR5GIP —RC2IP TX2IP CTMUIP CCP2IP CCP1IP RTCCIP
TRISC TRISC7 TRISC6 TRISC5 TRISC4 TRISC3 TRISC2 TRISC1 TRISC0
TRISD TRISD7 TRISD6 TRISD5 TRISD4 TRISD3 TRISD2 TRISD1 TRISD0
SSP1BUF MSSP1 Receive Buffer/Transmit Register
SSP1ADD MSSP1 Address Register (I2C Slave mode),
MSSP1 Baud Rate Reload Register (I2C Master mode)
SSP1MSK(1) MSK7 MSK6 MSK5 MSK4 MSK3 MSK2 MSK1 MSK0
SSP1CON1 WCOL SSPOV SSPEN CKP SSPM3 SSPM2 SSPM1 SSPM0
SSP1CON2 GCEN ACKSTAT ACKDT ACKEN RCEN PEN RSEN SEN
GCEN ACKSTAT ADMSK5(2) ADMSK4(2) ADMSK3(2) ADMSK2(2) ADMSK1(2) SEN
SSP1STAT SMP CKE D/A PSR/WUA BF
SSP2BUF MSSP2 Receive Buffer/Transmit Register
SSP2ADD MSSP2 Address Register (I2C Slave mode),
MSSP2 Baud Rate Reload Register (I2C Master mode)
SSP2MSK(1) MSK7 MSK6 MSK5 MSK4 MSK3 MSK2 MSK1 MSK0
SSP2CON1 WCOL SSPOV SSPEN CKP SSPM3 SSPM2 SSPM1 SSPM0
SSP2CON2 GCEN ACKSTAT ACKDT ACKEN RCEN PEN RSEN SEN
GCEN ACKSTAT ADMSK5(2) ADMSK4(2) ADMSK3(2) ADMSK2(2) ADMSK1(2) SEN
SSP2STAT SMP CKE D/A PSR/WUA BF
PMD0 CCP3MD CCP2MD CCP1MD UART2MD UART1MD SSP2MD SSP1MD ADCMD
Legend: — = unimplemented, read as ‘0’. Shaded cells are not used by the MSSP module in I2C™ mode.
Note 1: SSPxMSK shares the same address in SFR space as SSPxADD, but is only accessible in certain I2C
Slave operating modes in 7-Bit Masking mode. See Secti on 21.4.3.4 “7-Bit Addres s Masking Mod e” for
more details.
2: Alternate bit definitions for use in I2C Slave mode operations only.
2011 Microchip Technology Inc. DS39960C-page 327
PIC18F87K22 FAMILY
22.0 ENHANCED UNIVERSAL
SYNCHRONOUS
ASYNCHRONOUS RECEIVER
TRANSMITTER (EUSART)
The Enhanced Universal Synchronous Asynchronous
Receiver Transmitter (EUSART) module is one of two
serial I/O modules. (Generically, the EUSART is also
known as a Serial Communications Interface or SCI.)
The EUSART can be configured as a full-duplex,
asynchronous system that can communicate with
peripheral devices, such as CRT terminals and
personal computers. It can also be configured as a
half-duplex synchronous system that can communicate
with peripheral devices, such as A/D or D/A integrated
circuits, serial EEPROMs, etc.
The Enhanced USART module implements additional
features, including automatic baud rate detection and
calibration, automatic wake-up on Sync Break recep-
tion and 12-bit Break character transmit. These make it
ideally suited for use in Local Interconnect Network bus
(LIN/J2602 bus) systems.
All members of the PIC18F87K22 family are equipped
with two independent EUSART modules, referred to as
EUSART1 and EUSART2. They can be configured in
the following modes:
• Asynchronous (full duplex) with:
- Auto-wake-up on character reception
- Auto-baud calibration
- 12-bit Break character transmission
• Synchronous – Master (half duplex) with
selectable clock polarity
• Synchronous – Slave (half duplex) with selectable
clock polarity
The pins of EUSART1 and EUSART2 are multiplexed
with the functions of PORTC (RC6/TX1/CK1 and
RC7/RX1/DT1) and PORTG (RG1/TX2/CK2/AN19/C3OUT
and RG2/RX2/DT2/AN18/C3INA), respectively. In
order to configure these pins as an EUSART:
• For EUSART1:
- Bit, SPEN (RCSTA1<7>), must be set (= 1)
- Bit, TRISC<7>, must be set (= 1)
- Bit, TRISC<6>, must be cleared (= 0) for
Asynchronous and Synchronous Master
modes
- Bit, TRISC<6>, must be set (= 1) for
Synchronous Slave mode
• For EUSART2:
- Bit, SPEN (RCSTA2<7>), must be set (= 1)
- Bit, TRISG<2>, must be set (= 1)
- Bit TRISG<1> must be cleared (= 0) for
Asynchronous and Synchronous Master
modes
- Bit, TRISC<6>, must be set (= 1) for
Synchronous Slave mode
The operation of each Enhanced USART module is
controlled through three registers:
• Transmit Status and Control (TXSTAx)
• Receive Status and Control (RCSTAx)
• Baud Rate Control (BAUDCONx)
These are detailed on the following pages in
Register 22-1, Register 22-2 and Register 22-3,
respectively.
Note: The EUSART control will automatically
reconfigure the pin from input to output as
needed.
Note: Throughout this section, references to
register and bit names that may be asso-
ciated with a specific EUSART module are
referred to generically by the use of ‘x’ in
place of the specific module number.
Thus, “RCSTAx” might refer to the
Receive Status register for either
EUSART1 or EUSART2.
PIC18F87K22 FAMILY
DS39960C-page 328 2011 Microchip Technology Inc.
REGISTER 22-1: TXSTAx: TRANSMIT STATUS AND CONTROL REGISTER
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R-1 R/W-0
CSRC TX9 TXEN(1) SYNC SENDB BRGH TRMT TX9D
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 CSRC: Clock Source Select bit
Asynchronous mode:
Don’t care.
Synchronous mode:
1 = Master mode (clock generated internally from BRG)
0 = Slave mode (clock from external source)
bit 6 TX9: 9-Bit Transmit Enable bit
1 = Selects 9-bit transmission
0 = Selects 8-bit transmission
bit 5 TXEN: Transmit Enable bit(1)
1 = Transmit is enabled
0 = Transmit is disabled
bit 4 SYNC: EUSART Mode Select bit
1 = Synchronous mode
0 = Asynchronous mode
bit 3 SENDB: Send Break Character bit
Asynchronous mode:
1 = Send Sync Break on next transmission (cleared by hardware upon completion)
0 = Sync Break transmission has completed
Synchronous mode:
Don’t care.
bit 2 BRGH: High Baud Rate Select bit
Asynchronous mode:
1 = High speed
0 = Low speed
Synchronous mode:
Unused in this mode.
bit 1 TRMT: Transmit Shift Register Status bit
1 = TSR is empty
0 = TSR is full
bit 0 TX9D: 9th bit of Transmit Data
Can be address/data bit or a parity bit.
Note 1: SREN/CREN overrides TXEN in Sync mode.
2011 Microchip Technology Inc. DS39960C-page 329
PIC18F87K22 FAMILY
REGISTER 22-2: RCSTAx: RECEIVE STATUS AND CONTROL REGISTER
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R-0 R-0 R-x
SPEN RX9 SREN CREN ADDEN FERR OERR RX9D
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 SPEN: Serial Port Enable bit
1 = Serial port is enabled
0 = Serial port is disabled (held in Reset)
bit 6 RX9: 9-Bit Receive Enable bit
1 = Selects 9-bit reception
0 = Selects 8-bit reception
bit 5 SREN: Single Receive Enable bit
Asynchronous mode:
Don’t care.
Synchronous mode – Master:
1 = Enables single receive
0 = Disables single receive
This bit is cleared after reception is complete.
Synchronous mode – Slave:
Don’t care.
bit 4 CREN: Continuous Receive Enable bit
Asynchronous mode:
1 = Enables receiver
0 = Disables receiver
Synchronous mode:
1 = Enables continuous receive until enable bit, CREN, is cleared (CREN overrides SREN)
0 = Disables continuous receive
bit 3 ADDEN: Address Detect Enable bit
Asynchronous mode 9-Bit (RX9 = 1):
1 = Enables address detection, enables interrupt and loads the receive buffer when RSR<8> is set
0 = Disables address detection, all bytes are received and the ninth bit can be used as a parity bit
Asynchronous mode 9-Bit (RX9 = 0):
Don’t care.
bit 2 FERR: Framing Error bit
1 = Framing error (can be cleared by reading the RCREGx register and receiving the next valid byte)
0 = No framing error
bit 1 OERR: Overrun Error bit
1 = Overrun error (can be cleared by clearing bit, CREN)
0 = No overrun error
bit 0 RX9D: 9th bit of Received Data
This can be an address/data bit or a parity bit and must be calculated by user firmware.
PIC18F87K22 FAMILY
DS39960C-page 330 2011 Microchip Technology Inc.
REGISTER 22-3: BAUDCONx: BAUD RATE CONTROL REGISTER
R/W-0 R-1 R/W-0 R/W-0 R/W-0 U-0 R/W-0 R/W-0
ABDOVF RCIDL RXDTP TXCKP BRG16 — WUE ABDEN
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 ABDOVF: Auto-Baud Acquisition Rollover Status bit
1 = A BRG rollover has occurred during Auto-Baud Rate Detect mode (must be cleared in software)
0 = No BRG rollover has occurred
bit 6 RCIDL: Receive Operation Idle Status bit
1 = Receive operation is Idle
0 = Receive operation is active
bit 5 RXDTP: Data/Receive Polarity Select bit
Asynchronous mode:
1 = Receive data (RXx) is inverted (active-low)
0 = Receive data (RXx) is not inverted (active-high)
Synchronous mode:
1 = Data (DTx) is inverted (active-low)
0 = Data (DTx) is not inverted (active-high)
bit 4 TXCKP: Synchronous Clock Polarity Select bit
Asynchronous mode:
1 = Idle state for transmit (TXx) is a low level
0 = Idle state for transmit (TXx) is a high level
Synchronous mode:
1 = Idle state for clock (CKx) is a high level
0 = Idle state for clock (CKx) is a low level
bit 3 BRG16: 16-Bit Baud Rate Register Enable bit
1 = 16-bit Baud Rate Generator – SPBRGHx and SPBRGx
0 = 8-bit Baud Rate Generator – SPBRGx only (Compatible mode), SPBRGHx value ignored
bit 2 Unimplemented: Read as ‘0’
bit 1 WUE: Wake-up Enable bit
Asynchronous mode:
1 = EUSART will continue to sample the RXx pin – interrupt generated on falling edge; bit cleared in
hardware on following rising edge
0 = RXx pin not monitored or rising edge detected
Synchronous mode:
Unused in this mode.
bit 0 ABDEN: Auto-Baud Detect Enable bit
Asynchronous mode:
1 = Enable baud rate measurement on the next character. Requires reception of a Sync field (55h);
cleared in hardware upon completion.
0 = Baud rate measurement is disabled or has completed
Synchronous mode:
Unused in this mode.
2011 Microchip Technology Inc. DS39960C-page 331
PIC18F87K22 FAMILY
22.1 Baud Rate Generator (BRG)
The BRG is a dedicated, 8-bit or 16-bit generator that
supports both the Asynchronous and Synchronous
modes of the EUSART. By default, the BRG operates
in 8-bit mode; setting the BRG16 bit (BAUDCONx<3>)
selects 16-bit mode.
The SPBRGHx:SPBRGx register pair controls the period
of a free-running timer. In Asynchronous mode, bits,
BRGH (TXSTAx<2>) and BRG16 (BAUDCONx<3>),
also control the baud rate. In Synchronous mode, BRGH
is ignored. Table 22-1 shows the formula for computation
of the baud rate for different EUSART modes which only
apply in Master mode (internally generated clock).
Given the desired baud rate and FOSC, the nearest
integer value for the SPBRGHx:SPBRGx registers can
be calculated using the formulas in Tab le 2 2-1 . From this,
the error in baud rate can be determined. An example
calculation is shown in Example 22-1. Typical baud rates
and error values for the various Asynchronous modes
are shown in Ta b l e 2 2 - 2. It may be advantageous to use
the high baud rate (BRGH = 1) or the 16-bit BRG to
reduce the baud rate error, or achieve a slow baud rate
for a fast oscillator frequency.
Writing a new value to the SPBRGHx:SPBRGx
registers causes the BRG timer to be reset (or cleared).
This ensures the BRG does not wait for a timer over-
flow before outputting the new baud rate. When
operated in the Synchronous mode, SPBRGH:SPBRG
values of 0000h and 0001h are not supported. In the
Asynchronous mode, all BRG values may be used.
22.1.1 OPERATION IN POWER-MANAGED
MODES
The device clock is used to generate the desired baud
rate. When one of the power-managed modes is
entered, the new clock source may be operating at a
different frequency. This may require an adjustment to
the value in the SPBRGx register pair.
22.1.2 SAMPLING
The data on the RXx pin (either RC7/RX1/DT1 or
RG2/RX2/DT2/AN18/C3INA) is sampled three times
by a majority detect circuit to determine if a high or a
low level is present at the RXx pin.
TABLE 22-1: BAUD RATE FORMULAS
Configuration Bits BRG/EUSART Mode Baud Rate Formula
SYNC BRG16 BRGH
000 8-bit/Asynchronous FOSC/[64 (n + 1)]
001 8-bit/Asynchronous FOSC/[16 (n + 1)]
010 16-bit/Asynchronous
011 16-bit/Asynchronous
FOSC/[4 (n + 1)]10x 8-bit/Synchronous
11x 16-bit/Synchronous
Legend: x = Don’t care, n = value of SPBRGHx:SPBRGx register pair
PIC18F87K22 FAMILY
DS39960C-page 332 2011 Microchip Technology Inc.
EXAMPLE 22-1: CALCULATING BAUD RATE ERROR
TABLE 22-2: REGISTERS ASSOCIATED WITH BAUD RATE GENERATOR
Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
TXSTA1 CSRC TX9 TXEN SYNC SENDB BRGH TRMT TX9D
RCSTA1 SPEN RX9 SREN CREN ADDEN FERR OERR RX9D
BAUDCON1 ABDOVF RCIDL RXDTP TXCKP BRG16 —WUE ABDEN
SPBRGH1 EUSART1 Baud Rate Generator Register High Byte
SPBRG1 EUSART1 Baud Rate Generator Register
TXSTA2 CSRC TX9 TXEN SYNC SENDB BRGH TRMT TX9D
RCSTA2 SPEN RX9 SREN CREN ADDEN FERR OERR RX9D
BAUDCON2 ABDOVF RCIDL RXDTP TXCKP BRG16 —WUE ABDEN
SPBRGH2 EUSART2 Baud Rate Generator Register High Byte
SPBRG2 EUSART2 Baud Rate Generator Register
PMD0 CCP3MD CCP2MD CCP1MD UART2MD UART1MD SSP2MD SSP1MD ADCMD
Legend: — = unimplemented, read as ‘0’. Shaded cells are not used by the BRG.
For a device with FOSC of 16 MHz, desired baud rate of 9600, Asynchronous mode, and 8-bit BRG:
Desired Baud Rate = FOSC/(64 ([SPBRGHx:SPBRGx] + 1))
Solving for SPBRGHx:SPBRGx:
X = ((FOSC/Desired Baud Rate)/64) – 1
= ((16000000/9600)/64) – 1
= [25.042] = 25
Calculated Baud Rate = 16000000/(64 (25 + 1))
= 9615
Error = (Calculated Baud Rate – Desired Baud Rate)/Desired Baud Rate
= (9615 – 9600)/9600 = 0.16%
2011 Microchip Technology Inc. DS39960C-page 333
PIC18F87K22 FAMILY
TABLE 22-3: BAUD RATES FOR ASYNCHRONOUS MODES
BAUD
RATE
(K)
SYNC = 0, BRGH = 0, BRG16 = 0
FOSC = 40.000 MHz FOSC = 20.000 MHz FOSC = 10.000 MHz FOSC = 8.000 MHz
Actual
Rate
(K)
%
Error
SPBRG
value
(decimal)
Actual
Rate
(K)
%
Error
SPBRG
value
(decimal)
Actual
Rate
(K)
%
Error
SPBRG
value
(decimal)
Actual
Rate
(K)
%
Error
SPBRG
value
(decimal)
0.3————————————
1.2 — — — 1.221 1.73 255 1.202 0.16 129 1.201 -0.16 103
2.4 2.441 1.73 255 2.404 0.16 129 2.404 0.16 64 2.403 -0.16 51
9.6 9.615 0.16 64 9.766 1.73 31 9.766 1.73 15 9.615 -0.16 12
19.2 19.531 1.73 31 19.531 1.73 15 19.531 1.73 7 — — —
57.6 56.818 -1.36 10 62.500 8.51 4 52.083 -9.58 2 — — —
115.2 125.000 8.51 4 104.167 -9.58 2 78.125 -32.18 1 — — —
BAUD
RATE
(K)
SYNC = 0, BRGH = 0, BRG16 = 0
FOSC = 4.000 MHz FOSC = 2.000 MHz FOSC = 1.000 MHz
Actual
Rate
(K)
%
Error
SPBRG
value
(decimal)
Actual
Rate
(K)
%
Error
SPBRG
value
(decimal)
Actual
Rate
(K)
%
Error
SPBRG
value
(decimal)
0.3 0.300 0.16 207 0.300 -0.16 103 0.300 -0.16 51
1.2 1.202 0.16 51 1.201 -0.16 25 1.201 -0.16 12
2.4 2.404 0.16 25 2.403 -0.16 12 — — —
9.6 8.929 -6.99 6 — — — — — —
19.2 20.833 8.51 2 — — — — — —
57.6 62.500 8.51 0 — — — — — —
115.2 62.500 -45.75 0 — — — — — —
BAUD
RATE
(K)
SYNC = 0, BRGH = 1, BRG16 = 0
FOSC = 40.000 MHz FOSC = 20.000 MHz FOSC = 10.000 MHz FOSC = 8.000 MHz
Actual
Rate
(K)
%
Error
SPBRG
value
(decimal)
Actual
Rate
(K)
%
Error
SPBRG
value
(decimal)
Actual
Rate
(K)
%
Error
SPBRG
value
(decimal)
Actual
Rate
(K)
%
Error
SPBRG
value
(decimal)
0.3————————————
1.2————————————
2.4 — — — — — — 2.441 1.73 255 2.403 -0.16 207
9.6 9.766 1.73 255 9.615 0.16 129 9.615 0.16 64 9.615 -0.16 51
19.2 19.231 0.16 129 19.231 0.16 64 19.531 1.73 31 19.230 -0.16 25
57.6 58.140 0.94 42 56.818 -1.36 21 56.818 -1.36 10 55.555 3.55 8
115.2 113.636 -1.36 21 113.636 -1.36 10 125.000 8.51 4 — — —
BAUD
RATE
(K)
SYNC = 0, BRGH = 1, BRG16 = 0
FOSC = 4.000 MHz FOSC = 2.000 MHz FOSC = 1.000 MHz
Actual
Rate
(K)
%
Error
SPBRG
value
(decimal)
Actual
Rate
(K)
%
Error
SPBRG
value
(decimal)
Actual
Rate
(K)
%
Error
SPBRG
value
(decimal)
0.3 — — — — — — 0.300 -0.16 207
1.2 1.202 0.16 207 1.201 -0.16 103 1.201 -0.16 51
2.4 2.404 0.16 103 2.403 -0.16 51 2.403 -0.16 25
9.6 9.615 0.16 25 9.615 -0.16 12 — — —
19.2 19.231 0.16 12 — — — — — —
57.6 62.500 8.51 3 — — — — — —
115.2 125.000 8.51 1 — — — — — —
PIC18F87K22 FAMILY
DS39960C-page 334 2011 Microchip Technology Inc.
BAUD
RATE
(K)
SYNC = 0, BRGH = 0, BRG16 = 1
FOSC = 40.000 MHz FOSC = 20.000 MHz FOSC = 10.000 MHz FOSC = 8.000 MHz
Actual
Rate
(K)
%
Error
SPBRG
value
(decimal)
Actual
Rate
(K)
%
Error
SPBRG
value
(decimal)
Actual
Rate
(K)
%
Error
SPBRG
value
(decimal)
Actual
Rate
(K)
%
Error
SPBRG
value
(decimal)
0.3 0.300 0.00 8332 0.300 0.02 4165 0.300 0.02 2082 0.300 -0.04 1665
1.2 1.200 0.02 2082 1.200 -0.03 1041 1.200 -0.03 520 1.201 -0.16 415
2.4 2.402 0.06 1040 2.399 -0.03 520 2.404 0.16 259 2.403 -0.16 207
9.6 9.615 0.16 259 9.615 0.16 129 9.615 0.16 64 9.615 -0.16 51
19.2 19.231 0.16 129 19.231 0.16 64 19.531 1.73 31 19.230 -0.16 25
57.6 58.140 0.94 42 56.818 -1.36 21 56.818 -1.36 10 55.555 3.55 8
115.2 113.636 -1.36 21 113.636 -1.36 10 125.000 8.51 4 — — —
BAUD
RATE
(K)
SYNC = 0, BRGH = 0, BRG16 = 1
FOSC = 4.000 MHz FOSC = 2.000 MHz FOSC = 1.000 MHz
Actual
Rate
(K)
%
Error
SPBRG
value
(decimal)
Actual
Rate
(K)
%
Error
SPBRG
value
(decimal)
Actual
Rate
(K)
%
Error
SPBRG
value
(decimal)
0.3 0.300 0.04 832 0.300 -0.16 415 0.300 -0.16 207
1.2 1.202 0.16 207 1.201 -0.16 103 1.201 -0.16 51
2.4 2.404 0.16 103 2.403 -0.16 51 2.403 -0.16 25
9.6 9.615 0.16 25 9.615 -0.16 12 — — —
19.2 19.231 0.16 12 — — — — — —
57.6 62.500 8.51 3 — — — — — —
115.2 125.000 8.51 1 — — — — — —
BAUD
RATE
(K)
SYNC = 0, BRGH = 1, BRG16 = 1 or SYNC = 1, BRG16 = 1
FOSC = 40.000 MHz FOSC = 20.000 MHz FOSC = 10.000 MHz FOSC = 8.000 MHz
Actual
Rate
(K)
%
Error
SPBRG
value
(decimal)
Actual
Rate
(K)
%
Error
SPBRG
value
(decimal)
Actual
Rate
(K)
%
Error
SPBRG
value
(decimal)
Actual
Rate
(K)
%
Error
SPBRG
value
(decimal)
0.3 0.300 0.00 33332 0.300 0.00 16665 0.300 0.00 8332 0.300 -0.01 6665
1.2 1.200 0.00 8332 1.200 0.02 4165 1.200 0.02 2082 1.200 -0.04 1665
2.4 2.400 0.02 4165 2.400 0.02 2082 2.402 0.06 1040 2.400 -0.04 832
9.6 9.606 0.06 1040 9.596 -0.03 520 9.615 0.16 259 9.615 -0.16 207
19.2 19.193 -0.03 520 19.231 0.16 259 19.231 0.16 129 19.230 -0.16 103
57.6 57.803 0.35 172 57.471 -0.22 86 58.140 0.94 42 57.142 0.79 34
115.2 114.943 -0.22 86 116.279 0.94 42 113.636 -1.36 21 117.647 -2.12 16
BAUD
RATE
(K)
SYNC = 0, BRGH = 1, BRG16 = 1 or SYNC = 1, BRG16 = 1
FOSC = 4.000 MHz FOSC = 2.000 MHz FOSC = 1.000 MHz
Actual
Rate
(K)
%
Error
SPBRG
value
(decimal)
Actual
Rate
(K)
%
Error
SPBRG
value
(decimal)
Actual
Rate
(K)
%
Error
SPBRG
value
(decimal)
0.3 0.300 0.01 3332 0.300 -0.04 1665 0.300 -0.04 832
1.2 1.200 0.04 832 1.201 -0.16 415 1.201 -0.16 207
2.4 2.404 0.16 415 2.403 -0.16 207 2.403 -0.16 103
9.6 9.615 0.16 103 9.615 -0.16 51 9.615 -0.16 25
19.2 19.231 0.16 51 19.230 -0.16 25 19.230 -0.16 12
57.6 58.824 2.12 16 55.555 3.55 8 — — —
115.2 111.111 -3.55 8 — — — — — —
TABLE 22-3: BAUD RATES FOR ASYNCHRONOUS MODES (CONTINUED)
2011 Microchip Technology Inc. DS39960C-page 335
PIC18F87K22 FAMILY
22.1.3 AUTO-BAUD RATE DETECT
The Enhanced USART module supports the automatic
detection and calibration of baud rate. This feature is
active only in Asynchronous mode and while the WUE
bit is clear.
The automatic baud rate measurement sequence
(Figure 22-1) begins whenever a Start bit is received
and the ABDEN bit is set. The calculation is
self-averaging.
In the Auto-Baud Rate Detect (ABD) mode, the clock to
the BRG is reversed. Rather than the BRG clocking the
incoming RXx signal, the RXx signal is timing the BRG.
In ABD mode, the internal Baud Rate Generator is
used as a counter to time the bit period of the incoming
serial byte stream.
Once the ABDEN bit is set, the state machine will clear
the BRG and look for a Start bit. The Auto-Baud Rate
Detect must receive a byte with the value, 55h (ASCII
“U”, which is also the LIN/J2602 bus Sync character), in
order to calculate the proper bit rate. The measurement
is taken over both a low and a high bit time in order to
minimize any effects caused by asymmetry of the incom-
ing signal. After a Start bit, the SPBRGx begins counting
up, using the preselected clock source on the first rising
edge of RXx. After eight bits on the RXx pin or the fifth
rising edge, an accumulated value totalling the proper
BRG period is left in the SPBRGHx:SPBRGx register
pair. Once the 5th edge is seen (this should correspond
to the Stop bit), the ABDEN bit is automatically cleared.
If a rollover of the BRG occurs (an overflow from FFFFh
to 0000h), the event is trapped by the ABDOVF status
bit (BAUDCONx<7>). It is set in hardware by BRG roll-
overs and can be set or cleared by the user in software.
ABD mode remains active after rollover events and the
ABDEN bit remains set (Figure 22-2).
While calibrating the baud rate period, the BRG regis-
ters are clocked at 1/8th the preconfigured clock rate.
The BRG clock will be configured by the BRG16 and
BRGH bits. The BRG16 bit must be set to use both
SPBRG1 and SPBRGH1 as a 16-bit counter. This
allows the user to verify that no carry occurred for 8-bit
modes by checking for 00h in the SPBRGHx register.
Refer to Table 22-4 for counter clock rates to the BRG.
While the ABD sequence takes place, the EUSART
state machine is held in Idle. The RCxIF interrupt is set
once the fifth rising edge on RXx is detected. The value
in the RCREGx needs to be read to clear the RCxIF
interrupt. The contents of RCREGx should be
discarded.
TABLE 22-4: BRG COUNTER
CLOCK RATES
22.1.3.1 ABD and EUSART Transmission
Since the BRG clock is reversed during ABD acquisi-
tion, the EUSART transmitter cannot be used during
ABD. This means that whenever the ABDEN bit is set,
TXREGx cannot be written to. Users should also
ensure that ABDEN does not become set during a
transmit sequence. Failing to do this may result in
unpredictable EUSART operation.
Note 1: If the WUE bit is set with the ABDEN bit,
Auto-Baud Rate Detection will occur on
the byte following the Break character.
2: It is up to the user to determine that the
incoming character baud rate is within the
range of the selected BRG clock source.
Some combinations of oscillator
frequency and EUSART baud rates are
not possible due to bit error rates. Overall
system timing and communication baud
rates must be taken into consideration
when using the Auto-Baud Rate Detection
feature.
3: To maximize baud rate range, if that
feature is used it is recommended that
the BRG16 bit (BAUDCONx<3>) be set.
BRG16 BRGH BRG Counter Clock
00 FOSC/512
01 FOSC/128
10 FOSC/128
11 FOSC/32
PIC18F87K22 FAMILY
DS39960C-page 336 2011 Microchip Technology Inc.
FIGURE 22-1: AUTOMATIC BAUD RATE CALCULATION
FIGURE 22-2: BRG OVERFLOW SEQUENCE
BRG Value
RXx Pin
ABDEN bit
RCxIF bit
Bit 0 Bit 1
(Interrupt)
Read
RCREGx
BRG Clock
Start
Auto-Cleared
Set by User
XXXXh 0000h
Edge #1
Bit 2 Bit 3
Edge #2
Bit 4 Bit 5
Edge #3
Bit 6 Bit 7
Edge #4
001Ch
Note: The ABD sequence requires the EUSART module to be configured in Asynchronous mode and WUE = 0.
SPBRGx XXXXh 1Ch
SPBRGHx XXXXh 00h
Edge #5
Stop Bit
Start Bit 0
XXXXh 0000h 0000h
FFFFh
BRG Clock
ABDEN bit
RXx Pin
ABDOVF bit
BRG Value
2011 Microchip Technology Inc. DS39960C-page 337
PIC18F87K22 FAMILY
22.2 EUSART Asynchronous Mode
The Asynchronous mode of operation is selected by
clearing the SYNC bit (TXSTAx<4>). In this mode, the
EUSART uses standard Non-Return-to-Zero (NRZ)
format (one Start bit, eight or nine data bits and one Stop
bit). The most common data format is 8 bits. An on-chip,
dedicated 8-bit/16-bit Baud Rate Generator can be used
to derive standard baud rate frequencies from the
oscillator.
The EUSART transmits and receives the LSb first. The
EUSART’s transmitter and receiver are functionally
independent but use the same data format and baud
rate. The Baud Rate Generator produces a clock, either
x16 or x64 of the bit shift rate, depending on the BRGH
and BRG16 bits (TXSTAx<2> and BAUDCONx<3>).
Parity is not supported by the hardware but can be
implemented in software and stored as the 9th data bit.
When operating in Asynchronous mode, the EUSART
module consists of the following important elements:
• Baud Rate Generator
• Sampling Circuit
• Asynchronous Transmitter
• Asynchronous Receiver
• Auto-Wake-up on Sync Break Character
• 12-Bit Break Character Transmit
• Auto-Baud Rate Detection
22.2.1 EUSART ASYNCHRONOUS
TRANSMITTER
The EUSART transmitter block diagram is shown in
Figure 22-3. The heart of the transmitter is the Transmit
(Serial) Shift Register (TSR). The Shift register obtains
its data from the Read/Write Transmit Buffer register,
TXREGx. The TXREGx register is loaded with data in
software. The TSR register is not loaded until the Stop
bit has been transmitted from the previous load. As
soon as the Stop bit is transmitted, the TSR is loaded
with new data from the TXREGx register (if available).
Once the TXREGx register transfers the data to the TSR
register (occurs in one T
CY), the TXREGx register is
empty and the TXxIF flag bit is set. This interrupt can be
enabled or disabled by setting or clearing the interrupt
enable bit, TXxIE. TXxIF will be set regardless of the
state of TXxIE; it cannot be cleared in software. TXxIF is
also not cleared immediately upon loading TXREGx, but
becomes valid in the second instruction cycle following
the load instruction. Polling TXxIF immediately following
a load of TXREGx will return invalid results.
While TXxIF indicates the status of the TXREGx regis-
ter; another bit, TRMT (TXSTAx<1>), shows the status
of the TSR register. TRMT is a read-only bit which is set
when the TSR register is empty. No interrupt logic is
tied to this bit so the user has to poll this bit in order to
determine if the TSR register is empty.
To set up an Asynchronous Transmission:
1. Initialize the SPBRGHx:SPBRGx registers for
the appropriate baud rate. Set or clear the
BRGH and BRG16 bits, as required, to achieve
the desired baud rate.
2. Enable the asynchronous serial port by clearing
bit, SYNC, and setting bit, SPEN.
3. If interrupts are desired, set enable bit, TXxIE.
4. If 9-bit transmission is desired, set transmit bit,
TX9. Can be used as address/data bit.
5. Enable the transmission by setting bit, TXEN,
which will also set bit, TXxIF.
6. If 9-bit transmission is selected, the ninth bit
should be loaded in bit, TX9D.
7. Load data to the TXREGx register (starts
transmission).
8. If using interrupts, ensure that the GIE and PEIE
bits in the INTCON register (INTCON<7:6>) are
set.
FIGURE 22-3: EUS ART TRANSMIT BLOCK DIAGRAM
Note 1: The TSR register is not mapped in data
memory, so it is not available to the user.
2: Flag bit, TXxIF, is set when enable bit,
TXEN, is set.
TXxIF
TXxIE
Interrupt
TXEN Baud Rate CLK
SPBRGx
Baud Rate Generator TX9D
MSb LSb
Data Bus
TXREGx Register
TSR Register
(8) 0
TX9
TRMT SPEN
TXx Pin
Pin Buffer
and Control
8
SPBRGHx
BRG16
PIC18F87K22 FAMILY
DS39960C-page 338 2011 Microchip Technology Inc.
FIGURE 22-4: ASYNCHRONOUS TRANSMISSION
FIGURE 22-5: ASY NCHR ON OUS TRANSMISSION (BACK-TO-BACK)
Word 1
Word 1
Transmit Shift Reg
Start bit bit 0 bit 1 bit 7/8
Write to TXREGx
BRG Output
(Shift Clock)
TXx (pin)
TXxIF bit
(Transmit Buffer
Reg. Empty Flag)
TRMT bit
(Transmit Shift
Reg. Empty Flag)
1 TCY
Stop bit
Word 1
Transmit Shift Reg.
Write to TXREGx
BRG Output
(Shift Clock)
TXx (pin)
TXxIF bit
(Interrupt Reg. Flag)
TRMT bit
(Transmit Shift
Reg. Empty Flag)
Word 1 Word 2
Word 1 Word 2
Stop bit Start bit
Transmit Shift Reg.
Word 1 Word 2
bit 0 bit 1 bit 7/8 bit 0
Note: This timing diagram shows two consecutive transmissions.
1 TCY
1 TCY
Start bit
2011 Microchip Technology Inc. DS39960C-page 339
PIC18F87K22 FAMILY
TABLE 22-5: REGISTERS ASSOCIATED WITH ASYNCHRONOUS TRANSMISSION
Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 B it 1 Bit 0
INTCON GIE/GIEH PEIE/GIEL TMR0IE INT0IE RBIE TMR0IF INT0IF RBIF
PIR1 PSPIF ADIF RC1IF TX1IF SSP1IF TMR1GIF TMR2IF TMR1IF
PIE1 PSPIE ADIE RC1IE TX1IE SSP1IE TMR1GIE TMR2IE TMR1IE
IPR1 PSPIP ADIP RC1IP TX1IP SSP1IP TMR1GIP TMR2IP TMR1IP
PIR3 TMR5GIF — RC2IF TX2IF CTMUIF CCP2IF CCP1IF RTCCIF
PIE3 TMR5GIE —RC2IE TX2IE CTMUIE CCP2IE CCP1IE RTCCIE
IPR3 TMR5GIP —RC2IP TX2IP CTMUIP CCP2IP CCP1IP RTCCIP
RCSTA1 SPEN RX9 SREN CREN ADDEN FERR OERR RX9D
TXREG1 EUSART1 Transmit Register
TXSTA1 CSRC TX9 TXEN SYNC SENDB BRGH TRMT TX9D
BAUDCON1 ABDOVF RCIDL RXDTP TXCKP BRG16 —WUE ABDEN
SPBRGH1 EUSART1 Baud Rate Generator Register High Byte
SPBRG1 EUSART1 Baud Rate Generator Register
RCSTA2 SPEN RX9 SREN CREN ADDEN FERR OERR RX9D
TXREG2 EUSART2 Transmit Register
TXSTA2 CSRC TX9 TXEN SYNC SENDB BRGH TRMT TX9D
BAUDCON2 ABDOVF RCIDL RXDTP TXCKP BRG16 —WUE ABDEN
SPBRGH2 EUSART2 Baud Rate Generator Register High Byte
SPBRG2 EUSART2 Baud Rate Generator Register
ODCON3 U2OD U1OD — — — — — CTMUDS
PMD0 CCP3MD CCP2MD CCP1MD UART2MD UART1MD SSP2MD SSP1MD ADCMD
Legend: — = unimplemented locations read as ‘0’. Shaded cells are not used for asynchronous transmission.
PIC18F87K22 FAMILY
DS39960C-page 340 2011 Microchip Technology Inc.
22.2.2 EUSART ASYNCHRONOUS
RECEIVER
The receiver block diagram is shown in Figure 22-6.
The data is received on the RXx pin and drives the data
recovery block. The data recovery block is actually a
high-speed shifter operating at x16 times the baud rate,
whereas the main receive serial shifter operates at the
bit rate or at FOSC. This mode would typically be used
in RS-232 systems.
To set up an Asynchronous Reception:
1. Initialize the SPBRGHx:SPBRGx registers for
the appropriate baud rate. Set or clear the
BRGH and BRG16 bits, as required, to achieve
the desired baud rate.
2. Enable the asynchronous serial port by clearing
bit, SYNC, and setting bit, SPEN.
3. If interrupts are desired, set enable bit, RCxIE.
4. If 9-bit reception is desired, set bit, RX9.
5. Enable the reception by setting bit, CREN.
6. Flag bit, RCxIF, will be set when reception is
complete and an interrupt will be generated if
enable bit, RCxIE, was set.
7. Read the RCSTAx register to get the 9th bit (if
enabled) and determine if any error occurred
during reception.
8. Read the 8-bit received data by reading the
RCREGx register.
9. If any error occurred, clear the error by clearing
enable bit, CREN.
10. If using interrupts, ensure that the GIE and PEIE
bits in the INTCON register (INTCON<7:6>) are
set.
22.2.3 SETTING UP 9-BIT MODE WITH
ADDRESS DETECT
This mode would typically be used in RS-485 systems.
To set up an Asynchronous Reception with Address
Detect Enable:
1. Initialize the SPBRGHx:SPBRGx registers for
the appropriate baud rate. Set or clear the
BRGH and BRG16 bits, as required, to achieve
the desired baud rate.
2. Enable the asynchronous serial port by clearing
the SYNC bit and setting the SPEN bit.
3. If interrupts are required, set the RCEN bit and
select the desired priority level with the RCxIP bit.
4. Set the RX9 bit to enable 9-bit reception.
5. Set the ADDEN bit to enable address detect.
6. Enable reception by setting the CREN bit.
7. The RCxIF bit will be set when reception is
complete. The interrupt will be Acknowledged if
the RCxIE and GIE bits are set.
8. Read the RCSTAx register to determine if any
error occurred during reception, as well as read
bit 9 of data (if applicable).
9. Read RCREGx to determine if the device is
being addressed.
10. If any error occurred, clear the CREN bit.
11. If the device has been addressed, clear the
ADDEN bit to allow all received data into the
receive buffer and interrupt the CPU.
FIGURE 22-6: EUS ART RECEIVE BLOCK DIAGRAM
x64 Baud Rate CLK
Baud Rate Generator
RXx
Pin Buffer
and Control
SPEN
Data
Recovery
CREN OERR FERR
RSR Register
MSb LSb
RX9D RCREGx Register
FIFO
Interrupt RCxIF
RCxIE
Data Bus
8
64
16
or
Stop Start
(8) 7 1 0
RX9
SPBRGxSPBRGHx
BRG16
or
4
2011 Microchip Technology Inc. DS39960C-page 341
PIC18F87K22 FAMILY
FIGURE 22-7: ASYNCHRONOUS RECEPTION
TABLE 22-6: REGISTERS ASSOCIATED WITH ASYNCHRONOUS RECEPTION
Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
INTCON GIE/GIEH PEIE/GIEL TMR0IE INT0IE RBIE TMR0IF INT0IF RBIF
PIR1 PSPIF ADIF RC1IF TX1IF SSP1IF TMR1GIF TMR2IF TMR1IF
PIE1 PSPIE ADIE RC1IE TX1IE SSP1IE TMR1GIE TMR2IE TMR1IE
IPR1 PSPIP ADIP RC1IP TX1IP SSP1IP TMR1GIP TMR2IP TMR1IP
PIR3 TMR5GIF — RC2IF TX2IF CTMUIF CCP2IF CCP1IF RTCCIF
PIE3 TMR5GIE — RC2IE TX2IE CTMUIE CCP2IE CCP1IE RTCCIE
IPR3 TMR5GIP — RC2IP TX2IP CTMUIP CCP2IP CCP1IP RTCCIP
RCSTA1 SPEN RX9 SREN CREN ADDEN FERR OERR RX9D
RCREG1 EUSART1 Receive Register
TXSTA1 CSRC TX9 TXEN SYNC SENDB BRGH TRMT TX9D
BAUDCON1 ABDOVF RCIDL RXDTP TXCKP BRG16 — WUE ABDEN
SPBRGH1 EUSART1 Baud Rate Generator Register High Byte
SPBRG1 EUSART1 Baud Rate Generator Register
RCSTA2 SPEN RX9 SREN CREN ADDEN FERR OERR RX9D
RCREG2 EUSART2 Receive Register
TXSTA2 CSRC TX9 TXEN SYNC SENDB BRGH TRMT TX9D
BAUDCON2 ABDOVF RCIDL RXDTP TXCKP BRG16 —WUE ABDEN
SPBRGH2 EUSART2 Baud Rate Generator Register High Byte
SPBRG2 EUSART2 Baud Rate Generator Register
ODCON3 U2OD U1OD — — — — — CTMUDS
PMD0 CCP3MD CCP2MD CCP1MD UART2MD UART1MD SSP2MD SSP1MD ADCMD
Legend: — = unimplemented locations read as ‘0’. Shaded cells are not used for asynchronous reception.
Start
bit bit 7/8
bit 1bit 0 bit 7/8 bit 0
Stop
bit
Start
bit
Start
bit
bit 7/8 Stop
bit
RXx (pin)
Rcv Buffer Reg
Rcv Shift Reg
Read Rcv
Buffer Reg
RCREGx
RCxIF
(Interrupt Flag)
OERR bit
CREN
Word 1
RCREGx
Word 2
RCREGx
Stop
bit
Note: This timing diagram shows three words appearing on the RXx input. The RCREGx (Receive Buffer) is read after the third word,
causing the OERR (Overrun) bit to be set.
PIC18F87K22 FAMILY
DS39960C-page 342 2011 Microchip Technology Inc.
22.2.4 AUTO-WAKE-UP ON SYNC BREAK
CHARACTER
During Sleep mode, all clocks to the EUSART are
suspended. Because of this, the Baud Rate Generator
is inactive and a proper byte reception cannot be per-
formed. The auto-wake-up feature allows the controller
to wake-up due to activity on the RXx/DTx line while the
EUSART is operating in Asynchronous mode.
The auto-wake-up feature is enabled by setting the
WUE bit (BAUDCONx<1>). Once set, the typical
receive sequence on RXx/DTx is disabled and the
EUSART remains in an Idle state, monitoring for a
wake-up event independent of the CPU mode. A
wake-up event consists of a high-to-low transition on
the RXx/DTx line. (This coincides with the start of a
Sync Break or a Wake-up Signal character for the
LIN/J2602 protocol.)
Following a wake-up event, the module generates an
RCxIF interrupt. The interrupt is generated synchro-
nously to the Q clocks in normal operating modes
(Figure 22-8) and asynchronously if the device is in
Sleep mode (Figure 22-9). The interrupt condition is
cleared by reading the RCREGx register.
The WUE bit is automatically cleared once a low-to-high
transition is observed on the RXx line following the
wake-up event. At this point, the EUSART module is in
Idle mode and returns to normal operation. This signals
to the user that the Sync Break event is over.
22.2.4.1 Special Considerations Using
Auto-Wake-up
Since auto-wake-up functions by sensing rising edge
transitions on RXx/DTx, information with any state
changes before the Stop bit may signal a false
End-of-Character (EOC) and cause data or framing
errors. To work properly, therefore, the initial character
in the transmission must be all ‘0’s. This can be 00h
(8 bits) for standard RS-232 devices or 000h (12 bits)
for the LIN/J2602 bus.
Oscillator start-up time must also be considered,
especially in applications using oscillators with longer
start-up intervals (i.e., HS or HSPLL mode). The Sync
Break (or Wake-up Signal) character must be of
sufficient length and be followed by a sufficient interval
to allow enough time for the selected oscillator to start
and provide proper initialization of the EUSART.
2011 Microchip Technology Inc. DS39960C-page 343
PIC18F87K22 FAMILY
22.2.4.2 Special Considerations Using
the WUE Bit
The timing of WUE and RCxIF events may cause some
confusion when it comes to determining the validity of
received data. As noted, setting the WUE bit places the
EUSART in an Idle mode. The wake-up event causes a
receive interrupt by setting the RCxIF bit. The WUE bit
is cleared after this when a rising edge is seen on
RXx/DTx. The interrupt condition is then cleared by
reading the RCREGx register. Ordinarily, the data in
RCREGx will be dummy data and should be discarded.
The fact that the WUE bit has been cleared (or is still
set), and the RCxIF flag is set, should not be used as
an indicator of the integrity of the data in RCREGx.
Users should consider implementing a parallel method
in firmware to verify received data integrity.
To assure that no actual data is lost, check the RCIDL
bit to verify that a receive operation is not in process. If
a receive operation is not occurring, the WUE bit may
then be set just prior to entering the Sleep mode.
FIGURE 22-8: AUTO-WAKE-UP BIT (WUE) TIMINGS DURING NORMAL OPERATION
FIGURE 22-9: AUTO-WAKE-UP BIT (WUE) TIMINGS DURING SLEEP
Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4
OSC1
WUE bit(1)
RXx/DTx Line
RCxIF
Note 1:The EUSART remains in Idle while the WUE bit is set.
Bit Set by User
Cleared due to User Read of RCREGx
Auto-Cleared
Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4
OSC1
WUE bit(2)
RXx/DTx Line
RCxIF
Cleared due to User Read of RCREGx
SLEEP Command Executed
Note 1: If the wake-up event requires long oscillator warm-up time, the auto-clear of the WUE bit can occur before the oscillator is ready. This
sequence should not depend on the presence of Q clocks.
2: The EUSART remains in Idle while the WUE bit is set.
Sleep Ends
Note 1
Auto-Cleared
Bit Set by User
PIC18F87K22 FAMILY
DS39960C-page 344 2011 Microchip Technology Inc.
22.2.5 BREAK CHARACTER SEQUENCE
The EUSART module has the capability of sending the
special Break character sequences that are required by
the LIN/J2602 bus standard. The Break character
transmit consists of a Start bit, followed by twelve ‘0’
bits and a Stop bit. The Frame Break character is sent
whenever the SENDB and TXEN bits (TXSTAx<3> and
TXSTAx<5>, respectively) are set while the Transmit
Shift Register is loaded with data. Note that the value
of data written to TXREGx will be ignored and all ‘0’s
will be transmitted.
The SENDB bit is automatically reset by hardware after
the corresponding Stop bit is sent. This allows the user
to preload the transmit FIFO with the next transmit byte
following the Break character (typically, the Sync
character in the LIN/J2602 specification).
Note that the data value written to the TXREGx for the
Break character is ignored. The write simply serves the
purpose of initiating the proper sequence.
The TRMT bit indicates when the transmit operation is
active or Idle, just as it does during normal transmis-
sion. See Figure 22-10 for the timing of the Break
character sequence.
22.2.5.1 Break and Sync Transmit Sequence
The following sequence will send a message frame
header made up of a Break, followed by an Auto-Baud
Sync byte. This sequence is typical of a LIN/J2602 bus
master.
1. Configure the EUSART for the desired mode.
2. Set the TXEN and SENDB bits to set up the
Break character.
3. Load the TXREGx with a dummy character to
initiate transmission (the value is ignored).
4. Write ‘55h’ to TXREGx to load the Sync
character into the transmit FIFO buffer.
5. After the Break has been sent, the SENDB bit is
reset by hardware. The Sync character now
transmits in the preconfigured mode.
When the TXREGx becomes empty, as indicated by
the TXxIF, the next data byte can be written to
TXREGx.
22.2.6 RECEIVING A BREAK CHARACTER
The Enhanced USART module can receive a Break
character in two ways.
The first method forces configuration of the baud rate
at a frequency of 9/13 the typical speed. This allows for
the Stop bit transition to be at the correct sampling
location (13 bits for Break versus Start bit and 8 data
bits for typical data).
The second method uses the auto-wake-up feature
described in Section 22.2.4 “Auto-Wake-up on Sync
Break Character”. By enabling this feature, the
EUSART will sample the next two transitions on
RXx/DTx, cause an RCxIF interrupt and receive the
next data byte followed by another interrupt.
Note that following a Break character, the user will
typically want to enable the Auto-Baud Rate Detect
feature. For both methods, the user can set the ABDEN
bit once the TXxIF interrupt is observed.
FIGURE 22-10: SEND BREAK CHARACTER SEQUENCE
Write to TXREGx
BRG Output
(Shift Clock)
Start Bit Bit 0 Bit 1 Bit 11 Stop Bit
Break
TXxIF bit
(Transmit Buffer
Reg. Empty Flag)
TXx (pin)
TRMT bit
(Transmit Shift
Reg. Empty Flag)
SENDB bit
(Transmit Shift
Reg. Empty Flag)
SENDB sampled here Auto-Cleared
Dummy Write
2011 Microchip Technology Inc. DS39960C-page 345
PIC18F87K22 FAMILY
22.3 EUSART Synchronous
Master Mode
The Synchronous Master mode is entered by setting
the CSRC bit (TXSTAx<7>). In this mode, the data is
transmitted in a half-duplex manner (i.e., transmission
and reception do not occur at the same time). When
transmitting data, the reception is inhibited and vice
versa. Synchronous mode is entered by setting bit,
SYNC (TXSTAx<4>). In addition, enable bit, SPEN
(RCSTAx<7>), is set in order to configure the TXx and
RXx pins to CKx (clock) and DTx (data) lines,
respectively.
The Master mode indicates that the processor trans-
mits the master clock on the CKx line. Clock polarity is
selected with the TXCKP bit (BAUDCONx<4>). Setting
TXCKP sets the Idle state on CKx as high, while clear-
ing the bit sets the Idle state as low. This option is
provided to support Microwire devices with this module.
22.3.1 EUSART SYNCHRONOUS MASTER
TRANSMISSION
The EUSART transmitter block diagram is shown in
Figure 22-3. The heart of the transmitter is the Transmit
(Serial) Shift Register (TSR). The shift register obtains
its data from the Read/Write Transmit Buffer register,
TXREGx. The TXREGx register is loaded with data in
software. The TSR register is not loaded until the last
bit has been transmitted from the previous load. As
soon as the last bit is transmitted, the TSR is loaded
with new data from the TXREGx (if available).
Once the TXREGx register transfers the data to the
TSR register (occurs in one TCY), the TXREGx is empty
and the TXxIF flag bit is set. The interrupt can be
enabled or disabled by setting or clearing the interrupt
enable bit, TXxIE. TXxIF is set regardless of the state
of enable bit, TXxIE; it cannot be cleared in software. It
will reset only when new data is loaded into the
TXREGx register.
While flag bit, TXxIF, indicates the status of the TXREGx
register, another bit, TRMT (TXSTAx<1>), shows the
status of the TSR register. TRMT is a read-only bit which
is set when the TSR is empty. No interrupt logic is tied to
this bit, so the user must poll this bit in order to determine
if the TSR register is empty. The TSR is not mapped in
data memory so it is not available to the user.
To set up a Synchronous Master Transmission:
1. Initialize the SPBRGHx:SPBRGx registers for the
appropriate baud rate. Set or clear the BRG16
bit, as required, to achieve the desired baud rate.
2. Enable the synchronous master serial port by
setting bits, SYNC, SPEN and CSRC.
3. If interrupts are desired, set enable bit, TXxIE.
4. If 9-bit transmission is desired, set bit, TX9.
5. Enable the transmission by setting bit, TXEN.
6. If 9-bit transmission is selected, the ninth bit
should be loaded in bit, TX9D.
7. Start transmission by loading data to the
TXREGx register.
8. If using interrupts, ensure that the GIE and PEIE
bits in the INTCON register (INTCON<7:6>) are
set.
FIGURE 22-11: SYNCHRONOUS TRANSMISSION
bit 0 bit 1 bit 7
Word 1
Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4
bit 2 bit 0 bit 1 bit 7
Pin
RC6/TX1/CK1/
Write to
TxREG1 Reg
Tx1IF bit
(Interrupt Flag)
TXEN bit ‘1’ ‘1’
Word 2
TRMT bit
Write Word 1 Write Word 2
Note: Sync Master mode, SPBRGx = 0, continuous transmission of two 8-bit words. This example is equally applicable to EUSART2
(RG1/TX2/CK2/AN19/C3OUT and RG2/RX2/DT2/AN18/C3INA).
RC7/RX1/DT1/
Pin (TXCKP = 0)
RC6/TX1/CK1/
Pin (TXCKP = 1)
PIC18F87K22 FAMILY
DS39960C-page 346 2011 Microchip Technology Inc.
FIGURE 22-12: SYNCHRONOUS TRANSMISSION (THROUGH TXEN)
TABLE 22-7: REGISTERS ASSOCIATED WITH SYNCHRONOUS MASTER TRANSMISSION
Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
INTCON GIE/GIEH PEIE/GIEL TMR0IE INT0IE RBIE TMR0IF INT0IF RBIF
PIR1 PSPIF ADIF RC1IF TX1IF SSP1IF TMR1GIF TMR2IF TMR1IF
PIE1 PSPIE ADIE RC1IE TX1IE SSP1IE TMR1GIE TMR2IE TMR1IE
IPR1 PSPIP ADIP RC1IP TX1IP SSP1IP TMR1GIP TMR2IP TMR1IP
PIR3 TMR5GIF — RC2IF TX2IF CTMUIF CCP2IF CCP1IF RTCCIF
PIE3 TMR5GIE — RC2IE TX2IE CTMUIE CCP2IE CCP1IE RTCCIE
IPR3 TMR5GIP — RC2IP TX2IP CTMUIP CCP2IP CCP1IP RTCCIP
RCSTA1 SPEN RX9 SREN CREN ADDEN FERR OERR RX9D
TXREG1 EUSART1 Transmit Register
TXSTA1 CSRC TX9 TXEN SYNC SENDB BRGH TRMT TX9D
BAUDCON1 ABDOVF RCIDL RXDTP TXCKP BRG16 —WUE ABDEN
SPBRGH1 EUSART1 Baud Rate Generator Register High Byte
SPBRG1 EUSART1 Baud Rate Generator Register
RCSTA2 SPEN RX9 SREN CREN ADDEN FERR OERR RX9D
TXREG2 EUSART2 Transmit Register
TXSTA2 CSRC TX9 TXEN SYNC SENDB BRGH TRMT TX9D
BAUDCON2 ABDOVF RCIDL RXDTP TXCKP BRG16 —WUE ABDEN
SPBRGH2 EUSART2 Baud Rate Generator Register High Byte
SPBRG2 EUSART2 Baud Rate Generator Register
ODCON3 U2OD U1OD —————CTMUDS
PMD0 CCP3MD CCP2MD CCP1MD UART2MD UART1MD SSP2MD SSP1MD ADCMD
Legend: — = unimplemented, read as ‘0’. Shaded cells are not used for synchronous master transmission.
RC7/RX1/DT1 Pin
RC6/TX1/CK1 Pin
Write to
TXREG1 reg
TX1IF bit
TRMT bit
bit 0 bit 1 bit 2 bit 6 bit 7
TXEN bit
Note: This example is equally applicable to EUSART2 (RG1/TX2/CK2/AN19/C3OUT and RG2/RX2/DT2/AN18/C3INA).
2011 Microchip Technology Inc. DS39960C-page 347
PIC18F87K22 FAMILY
22.3.2 EUSART SYNCHRONOUS
MASTER RECEPTION
Once Synchronous mode is selected, reception is
enabled by setting either the Single Receive Enable bit,
SREN (RCSTAx<5>) or the Continuous Receive
Enable bit, CREN (RCSTAx<4>). Data is sampled on
the RXx pin on the falling edge of the clock.
If enable bit, SREN, is set, only a single word is
received. If enable bit, CREN, is set, the reception is
continuous until CREN is cleared. If both bits are set,
then CREN takes precedence.
To set up a Synchronous Master Reception:
1. Initialize the SPBRGHx:SPBRGx registers for the
appropriate baud rate. Set or clear the BRG16
bit, as required, to achieve the desired baud rate.
2. Enable the synchronous master serial port by
setting bits, SYNC, SPEN and CSRC.
3. Ensure bits, CREN and SREN, are clear.
4. If interrupts are desired, set enable bit, RCxIE.
5. If 9-bit reception is desired, set bit, RX9.
6. If a single reception is required, set bit, SREN.
For continuous reception, set bit, CREN.
7. Interrupt flag bit, RCxIF, will be set when recep-
tion is complete and an interrupt will be generated
if the enable bit, RCxIE, was set.
8. Read the RCSTAx register to get the 9th bit (if
enabled) and determine if any error occurred
during reception.
9. Read the 8-bit received data by reading the
RCREGx register.
10. If any error occurred, clear the error by clearing
bit CREN.
11. If using interrupts, ensure that the GIE and PEIE bits
in the INTCON register (INTCON<7:6>) are set.
FIGURE 22-13: SYNCHRONOUS RECEPTION (MASTER MODE, SREN)
CREN bit
Write to
bit, SREN
SREN bit
RC1IF bit
(Interrupt)
Read
RCREG1
Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4Q2 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4
‘
0
’
bit 0 bit 1 bit 2 bit 3 bit 4 bit 5 bit 6 bit 7
‘
0
’
Q1 Q2 Q3 Q4
Note: Timing diagram demonstrates Sync Master mode with bit, SREN = 1, and bit, BRGH = 0. This example is equally applicable to EUSART2
(RG1/TX2/CK2/AN19/C3OUT and RG2/RX2/DT2/AN18/C3INA).
Pin
RC7/RX1/DT1
RC6/TX1/CK1
Pin (TXCKP = 0)
RC6/TX1/CK1
Pin (TXCKP = 1)
PIC18F87K22 FAMILY
DS39960C-page 348 2011 Microchip Technology Inc.
TABLE 22-8: REGISTERS ASSOCIATED WITH SYNCHRONOUS MASTER RECEPTION
Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
INTCON GIE/GIEH PEIE/GIEL TMR0IE INT0IE RBIE TMR0IF INT0IF RBIF
PIR1 PSPIF ADIF RC1IF TX1IF SSP1IF TMR1GIF TMR2IF TMR1IF
PIE1 PSPIE ADIE RC1IE TX1IE SSP1IE TMR1GIE TMR2IE TMR1IE
IPR1 PSPIP ADIP RC1IP TX1IP SSP1IP TMR1GIP TMR2IP TMR1IP
PIR3 TMR5GIF —RC2IFTX2IF CTMUIF CCP2IF CCP1IF RTCCIF
PIE3 TMR5GIE —RC2IETX2IE CTMUIE CCP2IE CCP1IE RTCCIE
IPR3 TMR5GIP —RC2IPTX2IP CTMUIP CCP2IP CCP1IP RTCCIP
RCSTA1 SPEN RX9 SREN CREN ADDEN FERR OERR RX9D
RCREG1 EUSART1 Receive Register
TXSTA1 CSRC TX9 TXEN SYNC SENDB BRGH TRMT TX9D
BAUDCON1 ABDOVF RCIDL RXDTP TXCKP BRG16 —WUE ABDEN
SPBRGH1 EUSART1 Baud Rate Generator Register High Byte
SPBRG1 EUSART1 Baud Rate Generator Register
RCSTA2 SPEN RX9 SREN CREN ADDEN FERR OERR RX9D
RCREG2 EUSART2 Receive Register
TXSTA2 CSRC TX9 TXEN SYNC SENDB BRGH TRMT TX9D
BAUDCON2 ABDOVF RCIDL RXDTP TXCKP BRG16 —WUE ABDEN
SPBRGH2 EUSART2 Baud Rate Generator Register High Byte
SPBRG2 EUSART2 Baud Rate Generator Register
ODCON3 U2OD U1OD — — — — — CTMUDS
PMD0 CCP3MD CCP2MD CCP1MD UART2MD UART1MD SSP2MD SSP1MD ADCMD
Legend: — = unimplemented, read as ‘0’. Shaded cells are not used for synchronous master reception.
2011 Microchip Technology Inc. DS39960C-page 349
PIC18F87K22 FAMILY
22.4 EUSART Synchronous
Slave Mode
Synchronous Slave mode is entered by clearing bit,
CSRC (TXSTAx<7>). This mode differs from the
Synchronous Master mode in that the shift clock is sup-
plied externally at the CKx pin (instead of being supplied
internally in Master mode). This allows the device to
transfer or receive data while in any low-power mode.
22.4.1 EUSART SYNCHRONOUS
SLAVE TRANSMISSION
The operation of the Synchronous Master and Slave
modes is identical, except in the case of Sleep mode.
If two words are written to the TXREGx and then the
SLEEP instruction is executed, the following will occur:
a) The first word will immediately transfer to the
TSR register and transmit.
b) The second word will remain in the TXREGx
register.
c) Flag bit, TXxIF, will not be set.
d) When the first word has been shifted out of TSR,
the TXREGx register will transfer the second word
to the TSR and flag bit, TXxIF, will now be set.
e) If enable bit, TXxIE, is set, the interrupt will wake
the chip from Sleep. If the global interrupt is
enabled, the program will branch to the interrupt
vector.
To set up a Synchronous Slave Transmission:
1. Enable the synchronous slave serial port by
setting bits, SYNC and SPEN, and clearing bit,
CSRC.
2. Clear bits, CREN and SREN.
3. If interrupts are desired, set enable bit, TXxIE.
4. If 9-bit transmission is desired, set bit, TX9.
5. Enable the transmission by setting enable bit,
TXEN.
6. If 9-bit transmission is selected, the ninth bit
should be loaded in bit, TX9D.
7. Start transmission by loading data to the
TXREGx register.
8. If using interrupts, ensure that the GIE and PEIE
bits in the INTCON register (INTCON<7:6>) are
set.
TABLE 22-9: REGISTERS ASSOCIATED WITH SYNCHRONOUS SLAVE TRANSMISSION
Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
INTCON GIE/GIEH PEIE/GIEL TMR0IE INT0IE RBIE TMR0IF INT0IF RBIF
PIR1 PSPIF ADIF RC1IF TX1IF SSP1IF TMR1GIF TMR2IF TMR1IF
PIE1 PSPIE ADIE RC1IE TX1IE SSP1IE TMR1GIE TMR2IE TMR1IE
IPR1 PSPIP ADIP RC1IP TX1IP SSP1IP TMR1GIP TMR2IP TMR1IP
PIR3 TMR5GIF — RC2IF TX2IF CTMUIF CCP2IF CCP1IF RTCCIF
PIE3 TMR5GIE —RC2IE TX2IE CTMUIE CCP2IE CCP1IE RTCCIE
IPR3 TMR5GIP —RC2IP TX2IP CTMUIP CCP2IP CCP1IP RTCCIP
RCSTA1 SPEN RX9 SREN CREN ADDEN FERR OERR RX9D
TXREG1 EUSART1 Transmit Register
TXSTA1 CSRC TX9 TXEN SYNC SENDB BRGH TRMT TX9D
BAUDCON1 ABDOVF RCIDL RXDTP TXCKP BRG16 —WUE ABDEN
SPBRGH1 EUSART1 Baud Rate Generator Register High Byte
SPBRG1 EUSART1 Baud Rate Generator Register
RCSTA2 SPEN RX9 SREN CREN ADDEN FERR OERR RX9D
TXREG2 EUSART2 Transmit Register
TXSTA2 CSRC TX9 TXEN SYNC SENDB BRGH TRMT TX9D
BAUDCON2 ABDOVF RCIDL RXDTP TXCKP BRG16 —WUE ABDEN
SPBRGH2 EUSART2 Baud Rate Generator Register High Byte
SPBRG2 EUSART2 Baud Rate Generator Register
ODCON3 U2OD U1OD — — — — — CTMUDS
PMD0 CCP3MD CCP2MD CCP1MD UART2MD UART1MD SSP2MD SSP1MD ADCMD
Legend: — = unimplemented, read as ‘0’. Shaded cells are not used for synchronous slave transmission.
PIC18F87K22 FAMILY
DS39960C-page 350 2011 Microchip Technology Inc.
22.4.2 EUSART SYNCHRONOUS SLAVE
RECEPTION
The operation of the Synchronous Master and Slave
modes is identical, except in the case of Sleep, or any
Idle mode and bit, SREN, which is a “don’t care” in
Slave mode.
If receive is enabled by setting the CREN bit prior to
entering Sleep or any Idle mode, then a word may be
received while in this low-power mode. Once the word
is received, the RSR register will transfer the data to the
RCREGx register. If the RCxIE enable bit is set, the
interrupt generated will wake the chip from the
low-power mode. If the global interrupt is enabled, the
program will branch to the interrupt vector.
To set up a Synchronous Slave Reception:
1. Enable the synchronous master serial port by
setting bits, SYNC and SPEN, and clearing bit,
CSRC.
2. If interrupts are desired, set enable bit, RCxIE.
3. If 9-bit reception is desired, set bit, RX9.
4. To enable reception, set enable bit, CREN.
5. Flag bit, RCxIF, will be set when reception is
complete. An interrupt will be generated if
enable bit, RCxIE, was set.
6. Read the RCSTAx register to get the 9th bit (if
enabled) and determine if any error occurred
during reception.
7. Read the 8-bit received data by reading the
RCREGx register.
8. If any error occurred, clear the error by clearing
bit, CREN.
9. If using interrupts, ensure that the GIE and PEIE
bits in the INTCON register (INTCON<7:6>) are
set.
TABLE 22-10: REGISTERS ASSOCIATED WITH SYNCHRONOUS SLAVE RECEPTION
Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
INTCON GIE/GIEH PEIE/GIEL TMR0IE INT0IE RBIE TMR0IF INT0IF RBIF
PIR1 PSPIF ADIF RC1IF TX1IF SSP1IF TMR1GIF TMR2IF TMR1IF
PIE1 PSPIE ADIE RC1IE TX1IE SSP1IE TMR1GIE TMR2IE TMR1IE
IPR1 PSPIP ADIP RC1IP TX1IP SSP1IP TMR1GIP TMR2IP TMR1IP
PIR3 TMR5GIF — RC2IF TX2IF CTMUIF CCP2IF CCP1IF RTCCIF
PIE3 TMR5GIE — RC2IE TX2IE CTMUIE CCP2IE CCP1IE RTCCIE
IPR3 TMR5GIP — RC2IP TX2IP CTMUIP CCP2IP CCP1IP RTCCIP
RCSTA1 SPEN RX9 SREN CREN ADDEN FERR OERR RX9D
RCREG1 EUSART1 Receive Register
TXSTA1 CSRC TX9 TXEN SYNC SENDB BRGH TRMT TX9D
BAUDCON1 ABDOVF RCIDL RXDTP TXCKP BRG16 —WUE ABDEN
SPBRGH1 EUSART1 Baud Rate Generator Register High Byte
SPBRG1 EUSART1 Baud Rate Generator Register
RCSTA2 SPEN RX9 SREN CREN ADDEN FERR OERR RX9D
RCREG2 EUSART2 Receive Register
TXSTA2 CSRC TX9 TXEN SYNC SENDB BRGH TRMT TX9D
BAUDCON2 ABDOVF RCIDL RXDTP TXCKP BRG16 —WUE ABDEN
SPBRGH2 EUSART2 Baud Rate Generator Register High Byte
SPBRG2 EUSART2 Baud Rate Generator Register
ODCON3 U2OD U1OD — — — — — CTMUDS
PMD0 CCP3MD CCP2MD CCP1MD UART2MD UART1MD SSP2MD SSP1MD ADCMD
Legend: — = unimplemented, read as ‘0’. Shaded cells are not used for synchronous slave reception.
2011 Microchip Technology Inc. DS39960C-page 351
PIC18F87K22 FAMILY
23.0 12-BIT ANALOG-TO-DIGITAL
CONVERTER (A/D) MODULE
The Analog-to-Digital (A/D) Converter module in the
PIC18F87K22 family of devices has 16 inputs for the
64-pin devices and 24 inputs for the 80-pin devices.
This module allows conversion of an analog input
signal to a corresponding 12-bit digital number.
The module has these registers:
• A/D Control Register 0 (ADCON0)
• A/D Control Register 1 (ADCON1)
• A/D Control Register 2 (ADCON2)
• A/D Port Configuration Register 0 (ANCON0)
• A/D Port Configuration Register 1 (ANCON1)
• A/D Port Configuration Register 2 (ANCON2)
• ADRESH (the upper, A/D Results register)
• ADRESL (the lower, A/D Results register)
The ADCON0 register, shown in Register 23-1, con-
trols the operation of the A/D module. The ADCON1
register, shown in Register 23-2, configures the voltage
reference and special trigger selection. The ADCON2
register, shown in Register 23-3, configures the A/D
clock source and programmed acquisition time and
justification.
23.1 Differential A/D Converter
The converter in PIC18F87K22 family devices is
implemented as a differential A/D where the differential
voltage between two channels is measured and
converted to digital values (see Figure 23-1).
The converter also can be configured to measure a
voltage from a single input by clearing the CHSN bits
(ADCON1<2:0>). With this configuration, the negative
channel input is connected internally to AVSS (see
Figure 23-2).
FIGURE 23-1: DIFFERENTIAL CHANNEL
MEASUREMENT
Differential conversion feeds the two input channels to
a unity gain differential amplifier. The positive channel
input is selected using the CHS bits (ADCON0<6:2>)
and the negative channel input is selected using the
CHSN bits (ADCON1<2:0>).
The output from the amplifier is fed to the A/D Con-
verter, as shown in Figure 23-1. The 12-bit result is
available on the ADRESH and ADRESL registers. An
additional bit indicates if the 12-bit result is a positive or
negative value.
FIGURE 23-2: SINGLE CHANNEL
MEASUREMENT
In the Single Channel Measurement mode, the nega-
tive input is connected to AVSS by clearing the CHSN
bits (ADCON1<2:0>).
ADC
Positive Input
CHS<4:0>
Negative Input
CHSN<2:0>
ADC
Positive Input
CHS<4:0>
CHSN<2:0> = 000
PIC18F87K22 FAMILY
DS39960C-page 352 2011 Microchip Technology Inc.
23.2 A/D Registers
23.2.1 A/D CONTROL REGISTERS
REGISTER 23-1: ADCON0: A/D CONTROL REGISTER 0
U-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0
— CHS4 CHS3 CHS2 CHS1 CHS0 GO/DONE ADON
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 Unimplemented: Read as ‘0’
bit 6-2 CHS<4:0>: Analog Channel Select bits
00000 = Channel 00 (AN0) 10000 = Channel 16 (AN16)
00001 = Channel 01 (AN1) 10001 = Channel 17 (AN17)
00010 = Channel 02 (AN2) 10010 = Channel 18 (AN18)
00011 = Channel 03 (AN3) 10011 = Channel 19 (AN19)
00100 = Channel 04 (AN4) 10100 = Channel 20 (AN20)(1,2)
00101 = Channel 05 (AN5) 10101 = Channel 21 (AN21)(1,2)
00110 = Channel 06 (AN6) 10110 = Channel 22 (AN22)(1,2)
00111 = Channel 07 (AN7) 10111 = Channel 23 (AN23)(1,2)
01000 = Channel 08 (AN8) 11000 = (Reserved)(2)
01001 = Channel 09 (AN9) 11001 = (Reserved)(2)
01010 = Channel 10 (AN10) 11010 = (Reserved)(2)
01011 = Channel 11 (AN11) 11011 = (Reserved)(2)
01100 = Channel 12 (AN12)(1,2) 11100 = Channel 28 (Reserved CTMU)
01101 = Channel 13 (AN13)(1,2) 11101 = Channel 29 (Internal temperature diode)
01110 = Channel 14 (AN14)(1,2) 11110 = Channel 30 (VDDCORE)
01111 = Channel 15 (AN15)(1,2) 11111 = Channel 31 (v1.024V band gap)
bit 1 GO/DONE: A/D Conversion Status bit
1 = A/D (or calibration) cycle in progress. Setting this bit starts an A/D conversion cycle. The bit is
cleared automatically by hardware when the A/D conversion is completed.
0 = A/D conversion completed or not in progress
bit 0 ADON: A/D On bit
1 = A/D Converter is operating
0 = A/D conversion module is shut off and consuming no operating current
Note 1: These channels are not implemented on 64-pin devices.
2: Performing a conversion on unimplemented channels will return random values.
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REGISTER 23-2: ADCON1: A/D CONTROL REGISTER 1
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0
TRIGSEL1 TRIGSEL0 VCFG1 VCFG0 VNCFG CHSN2 CHSN1 CHSN0
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7-6 TRIGSEL<1:0>: Special Trigger Select bits
11 = Selects the special trigger from the RTCC
10 = Selects the special trigger from the Timer1
01 = Selects the special trigger from the CTMU
00 = Selects the special trigger from the ECCP2
bit 5-4 VCFG<1:0>: A/D VREF+ Configuration bits
11 = Internal VREF+ (4.096V)
10 = Internal VREF+ (2.048V)
01 = External VREF+
00 = AVDD
bit 3 VNCFG: A/D VREF- Configuration bit
1 =External VREF
0 =AVSS
bit 2-0 CHSN<2:0>: Analog Negative Channel Select bits
111 = Channel 07 (AN6)
110 = Channel 06 (AN5)
101 = Channel 05 (AN4)
100 = Channel 04 (AN3)
011 = Channel 03 (AN2)
010 = Channel 02 (AN1)
001 = Channel 01 (AN0)
000 = Channel 00 (AVSS)
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REGISTER 23-3: ADCON2: A/D CONTROL REGISTER 2
R/W-0 U-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0
ADFM — ACQT2 ACQT1 ACQT0 ADCS2 ADCS1 ADCS0
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 ADFM: A/D Result Format Select bit
1 = Right justified
0 = Left justified
bit 6 Unimplemented: Read as ‘0’
bit 5-3 ACQT<2:0>: A/D Acquisition Time Select bits
111 = 20 T
AD
110 = 16 TAD
101 = 12 TAD
100 = 8 TAD
011 = 6 TAD
010 = 4 TAD
001 = 2 TAD
000 = 0 TAD(1)
bit 2-0 ADCS<2:0>: A/D Conversion Clock Select bits
111 = FRC (clock derived from A/D RC oscillator)(1)
110 = FOSC/64
101 = FOSC/16
100 = FOSC/4
011 = FRC (clock derived from A/D RC oscillator)(1)
010 = FOSC/32
001 = FOSC/8
000 = FOSC/2
Note 1: If the A/D FRC clock source is selected, a delay of one TCY (instruction cycle) is added before the A/D
clock starts. This allows the SLEEP instruction to be executed before starting a conversion.
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23.2.2 A/D RESULT REGISTERS
The ADRESH:ADRESL register pair is where the 12-bit
A/D result and extended sign bits (ADSGN) are loaded
at the completion of a conversion. This register pair is
16 bits wide. The A/D module gives the flexibility of left
or right justifying the 12-bit result in the 16-bit result
register. The A/D Format Select bit (ADFM) controls
this justification.
Figure 23-3 shows the operation of the A/D result justi-
fication and location of the extended sign bits
(ADSGN). The extended sign bits allow for easier
16-bit math to be performed on the result.
When the A/D Converter is disabled, these 8-bit
registers can be used as two, general purpose registers.
FIGURE 23-3: A/D RESULT JUSTIFICATION
REGISTER 23-4: ADRESH: A/D RESULT HIGH BYTE REGISTER, LEFT JUSTIFIED (ADFM = 0)
R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x
ADRES11 ADRES10 ADRES9 ADRES8 ADRES7 ADRES6 ADRES5 ADRES4
bit 7
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7-0 ADRES<11:4>: A/D Result High Byte bits
Result bits ADSGN bit
ADRESH ADRESL ADRESH ADRESL
12-Bit Result
Left Justified
ADFM = 0
Right Justified
ADFM = 1
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REGISTER 23-5: ADRESL: A/D RESULT HIGH BYTE REGISTER, LEFT JUSTIFIED (ADFM = 0)
R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x
ADRES3 ADRES2 ADRES1 ADRES0 ADSGN ADSGN ADSGN ADSGN
bit 7
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7-4 ADRES<3:0>: A/D Result Low Byte bits
bit 3-0 ADSGN: A/D Result Sign bit
1 = A/D result is negative
0 = A/D result is positive
REGISTER 23-6: ADRESH: A/D RESULT HIGH BYTE REGISTER, RIGHT JUSTIFIED (ADFM = 1)
R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x
ADSGN ADSGN ADSGN ADSGN ADRES11 ADRES10 ADRES9 ADRES8
bit 7
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7-4 ADSGN: A/D Result Sign bit
1 = A/D result is negative
0 = A/D result is positive
bit 3-0 ADRESH<11:8>: A/D Result High Byte bits
REGISTER 23-7: ADRESL: A/D RESULT LOW BYTE REGISTER, RIGHT JUSTIFIED (ADFM = 1)
R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x
ADRES7 ADRES6 ADRES5 ADRES4 ADRES3 ADRES2 ADRES1 ADRES0
bit 7
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7-0 ADRES<7:0>: A/D Result Low Byte bits
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The ANCONx registers are used to configure the
operation of the I/O pin associated with each analog
channel. Clearing an ANSELx bit configures the
corresponding pin (ANx) to operate as a digital only I/O.
Setting a bit configures the pin to operate as an analog
input for either the A/D Converter or the comparator
module, with all digital peripherals disabled and digital
inputs read as ‘0’.
As a rule, I/O pins that are multiplexed with analog
inputs default to analog operation on any device Reset.
REGISTER 23-8: ANCON0: A/D PORT CONFIGURATION REGISTER 0
R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1
ANSEL7 ANSEL6 ANSEL5 ANSEL4 ANSEL3 ANSEL2 ANSEL1 ANSEL0
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7-0 ANSEL<7:0>: Analog Port Configuration bits (AN7 and AN0)
1 = Pin configured as an analog channel; digital input is disabled and any inputs read as ‘0’
0 = Pin configured as a digital port
REGISTER 23-9: ANCON1: A/D PORT CONFIGURATION REGISTER 1
R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1
ANSEL15(1) ANSEL14(1) ANSEL13(1) ANSEL12(1) ANSEL11 ANSEL10 ANSEL9 ANSEL8
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7-0 ANSEL<15:8>: Analog Port Configuration bits (AN15 through AN8)
1 = Pin configured as an analog channel, digital input is disabled and any inputs read as ‘0’
0 = Pin configured as a digital port
Note 1: AN15 through AN12 and AN20 to AN23 are implemented only on 80-pin devices. For 64-pin devices, the
corresponding ANSELx bits are still implemented for these channels, but have no effect.
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The analog reference voltage is software-selectable to
either the device’s positive and negative supply voltage
(AVDD and AVSS) or the voltage level on the
RA3/AN3/VREF+ and RA2/AN2/VREF- pins. VREF+ has
two additional internal voltage reference selections:
2.048V and 4.096V.
The A/D Converter can uniquely operate while the
device is in Sleep mode. To operate in Sleep, the A/D
conversion clock must be derived from the A/D’s
internal RC oscillator.
The output of the sample and hold is the input into the
converter, which generates the result via successive
approximation.
Each port pin associated with the A/D Converter can be
configured as an analog input or a digital I/O. The
ADRESH and ADRESL registers contain the result of
the A/D conversion. When the A/D conversion is com-
plete, the result is loaded into the ADRESH:ADRESL
register pair, the GO/DONE bit (ADCON0<1>) is
cleared and the A/D Interrupt Flag bit, ADIF (PIR1<6>),
is set.
A device Reset forces all registers to their Reset state.
This forces the A/D module to be turned off and any
conversion in progress is aborted. The value in the
ADRESH:ADRESL register pair is not modified for a
Power-on Reset. These registers will contain unknown
data after a Power-on Reset.
The block diagram of the A/D module is shown in
Figure 23-4.
REGISTER 23-10: ANCON2: A/D PORT CONFIGURATION REGISTER 2
R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1
ANSEL23(1) ANSEL22(1) ANSEL21(1) ANSEL20(1) ANSEL19 ANSEL18 ANSEL17 ANSEL16
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7-0 ANSEL<23:16>: Analog Port Configuration bits (AN23 through AN16)
1 = Pin configured as an analog channel; digital input is disabled and any inputs read as ‘0’
0 = Pin configured as a digital port
Note 1: AN15 through AN12 and AN 20 through AN23 are implemented only on 80-pin devices. For 64-pin
devices, the corresponding ANSELx bits are still implemented for these channels, but have no effect.
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FIGURE 23-4: A/D BLOCK DIAGRAM
VREF+
Reference
Voltage
VNCFG
CHS<4:0>
AN23(1)
AN22(1)
AN4
AN3
AN2
AN1
AN0
10111
10110
00100
00011
00010
00001
00000
12-Bit
A/D
VREF-
VSS(2)
Converter
1.024V Band Gap
VDDCORE
Reserved CTMU
(Unimplemented)
11111
11110
11101
11100
11011
11010
11001
11000
Note 1: Channels, AN15 through AN12, and AN20 through AN23, are not available on 64-pin devices.
2: I/O pins have diode protection to VDD and VSS.
(Unimplemented)
(Unimplemented)
(Unimplemented)
Negative Input Voltage
Positive Input Voltage CHSN<2:0>
AN6
AN5
AN0
AVSS
111
110
001
000
AN2
VCFG<1:0>
AN3
VDD
11
10
01
00
Internal VREF+
(4.096V)
Internal VREF+
(2.048V)
Reserved
Temperature Diode
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After the A/D module has been configured as desired,
the selected channel must be acquired before the
conversion can start. The analog input channels must
have their corresponding TRIS bits selected as an
input. To determine acquisition time, see Section 23.3
“A/D Acquisition Requirements”. After this acquisi-
tion time has elapsed, the A/D conversion can be
started. An acquisition time can be programmed to
occur between setting the GO/DONE bit and the actual
start of the conversion.
To do an A/D conversion, follow these steps:
1. Configure the A/D module:
• Configure the required ADC pins as analog
pins (ANCON0, ANCON1 and ANCON2)
• Set the voltage reference (ADCON1)
• Select the A/D positive and negative input
channels (ADCON0 and ADCON1)
• Select the A/D acquisition time (ADCON2)
• Select the A/D conversion clock (ADCON2)
• Turn on the A/D module (ADCON0)
2. Configure the A/D interrupt (if desired):
• Clear the ADIF bit (PIR1<6>)
• Set the ADIE bit (PIE1<6>)
• Set the GIE bit (INTCON<7>)
3. Wait the required acquisition time (if required).
4. Start the conversion:
• Set the GO/DONE bit (ADCON0<1>)
5. Wait for A/D conversion to complete, by either:
• Polling for the GO/DONE bit to be cleared
OR
• Waiting for the A/D interrupt
6. Read A/D Result registers (ADRESH:ADRESL)
and, if required, clear bit, ADIF.
7. For the next conversion, begin with Step 1 or 2,
as required.
The A/D conversion time per bit is defined as TAD.
Before the next acquisition starts, a minimum Wait
of 2 T
AD is required.
FIGURE 23-5: ANALOG INPUT MODEL
VAIN CPIN
RSANx
5 pF
VDD
VT = 0.6V
VT = 0.6V ILEAKAGE
RIC 1k
Sampling
Switch
SS RSS
CHOLD = 25 pF
VSS
Sampling Switch
1234
(k)
VDD
±100 nA
Legend: CPIN
VT
ILEAKAGE
RIC
SS
CHOLD
= Input Capacitance
= Threshold Voltage
= Leakage Current at the pin due to
= Interconnect Resistance
= Sampling Switch
= Sample/Hold Capacitance (from DAC)
various junctions
= Sampling Switch ResistanceRSS
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23.3 A/D Acquisition Requirements
For the A/D Converter to meet its specified accuracy,
the Charge Holding (CHOLD) capacitor must be allowed
to fully charge to the input channel voltage level. The
analog input model is shown in Figure 23-5. The
source impedance (RS) and the internal sampling
switch (RSS) impedance directly affect the time
required to charge the capacitor CHOLD. The sampling
switch (RSS) impedance varies over the device voltage
(VDD).
The source impedance affects the offset voltage at the
analog input (due to pin leakage current). The maxi-
mum recom mended impe dance for ana log sources
is 2.5 k. After the analog input channel is selected or
changed, the channel must be sampled for at least the
minimum acquisition time before starting a conversion.
To calculate the minimum acquisition time,
Equation 23-1 can be used. This equation assumes
that 1/2 LSb error is used (1,024 steps for the A/D). The
1/2 LSb error is the maximum error allowed for the A/D
to meet its specified resolution.
Equation 23-3 shows the calculation of the minimum
required acquisition time, T
ACQ. This calculation is
based on the following application system
assumptions:
EQUATION 23-1: ACQUISITION TIME
EQUATION 23-2: A/D MINIMUM CHARGING TIME
EQUATION 23-3: CALCULATING THE MINIMUM REQUIRED ACQUISITION TIME
Note: When the conversion is started, the
holding capacitor is disconnected from the
input pin.
•CHOLD =25 pF
• Rs = 2.5 k
• Conversion Error 1/2 LSb
•V
DD =3VRss = 2 k
• Temperature = 85C (system max.)
TACQ = Amplifier Settling Time + Holding Capacitor Charging Time + Temperature Coefficient
=T
AMP + TC + TCOFF
VHOLD = (VREF – (VREF/2048)) • (1 – e(-TC/CHOLD(RIC + RSS + RS)))
or
TC = -(CHOLD)(RIC + RSS + RS) ln(1/2048)
TACQ =TAMP + TC + TCOFF
TAMP =0.2 s
TCOFF = (Temp – 25C)(0.02 s/C)
(85C – 25C)(0.02 s/C)
1.2 s
Temperature coefficient is only required for temperatures > 25C. Below 25C, TCOFF = 0 ms.
TC = -(CHOLD)(RIC + RSS + RS) ln(1/2048) s
-(25 pF) (1 k + 2 k + 2.5 k) ln(0.0004883) s
1.05 s
TACQ =0.2 s + 1.05 s + 1.2 s
2.45 s
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23.4 Selecting and Configuring
Automatic A c q uis i tio n Time
The ADCON2 register allows the user to select an
acquisition time that occurs each time the GO/DONE
bit is set.
When the GO/DONE bit is set, sampling is stopped and
a conversion begins. The user is responsible for ensur-
ing the required acquisition time has passed between
selecting the desired input channel and setting the
GO/DONE bit.
This occurs when the ACQT<2:0> bits
(ADCON2<5:3>) remain in their Reset state (‘000’),
which is compatible with devices that do not offer
programmable acquisition times.
If desired, the ACQTx bits can be set to select a pro-
grammable acquisition time for the A/D module. When
the GO/DONE bit is set, the A/D module continues to
sample the input for the selected acquisition time, then
automatically begins a conversion. Since the acquisi-
tion time is programmed, there may be no need to wait
for an acquisition time between selecting a channel and
setting the GO/DONE bit.
In either case, when the conversion is completed, the
GO/DONE bit is cleared, the ADIF flag is set and the
A/D begins sampling the currently selected channel
again. If an acquisition time is programmed, there is
nothing to indicate if the acquisition time has ended or
if the conversion has begun.
23.5 Selecting the A/D Conversion
Clock
The A/D conversion time per bit is defined as TAD. The
A/D conversion requires 14 TAD per 12-bit conversion.
The source of the A/D conversion clock is
software-selectable.
The possible options for T
AD are:
•2 T
OSC
•4 TOSC
•8 TOSC
•16 TOSC
•32 TOSC
•64 T
OSC
• Using the internal RC Oscillator
For correct A/D conversions, the A/D conversion clock
(T
AD) must be as short as possible, but greater than
the minimum TAD. (For more information, see
Parameter 130 in Table 31-28.)
Table 23-1 shows the resultant TAD times derived from
the device operating frequencies and the A/D clock
source selected.
TABLE 23-1: TAD vs. DEVICE OPERATING
FREQUENCIES
23.6 Configuring Analog Port Pins
The ANCON0, ANCON1, ANCON2, TRISA, TRISF,
TRISG and TRISH registers control the operation of the
A/D port pins. The port pins needed as analog inputs
must have their corresponding TRISx bits set (input). If
the TRISx bit is cleared (output), the digital output level
(VOH or VOL) will be converted.
The A/D operation is independent of the state of the
CHS<3:0> bits and the TRISx bits.
AD Clock Source (TAD)Maximum
Device
Frequency
Operation ADCS<2:0>
2 TOSC 000 2.50 MHz
4 T
OSC 100 5.00 MHz
8 T
OSC 001 10.00 MHz
16 TOSC 101 20.00 MHz
32 TOSC 010 40.00 MHz
64 TOSC 110 64.00 MHz
RC(2) x11 1.00 MHz(1)
Note 1: The RC source has a typical TAD time of
4s.
2: For device frequencies above 1 MHz, the
device must be in Sleep mode for the
entire conversion or the A/D accuracy may
be out of specification.
Note 1: When reading the PORT register, all pins
configured as analog input channels will
read as cleared (a low level). Pins config-
ured as digital inputs will convert an
analog input. Analog levels on a digitally
configured input will be accurately
converted.
2: Analog levels on any pin defined as a
digital input may cause the digital input
buffer to consume current out of the
device’s specification limits.
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23.7 A/D Conversions
Figure 23-6 shows the operation of the A/D Converter
after the GO/DONE bit has been set and the
ACQT<2:0> bits are cleared. A conversion is started
after the following instruction to allow entry into Sleep
mode before the conversion begins.
Figure 23-7 shows the operation of the A/D Converter
after the GO/DONE bit has been set, the ACQT<2:0>
bits set to ‘010’ and a 4 TAD acquisition time selected.
Clearing the GO/DONE bit during a conversion will
abort the current conversion. The A/D Result register
pair will NOT be updated with the partially completed
A/D conversion sample. This means the
ADRESH:ADRESL registers will continue to contain
the value of the last completed conversion (or the last
value written to the ADRESH:ADRESL registers).
After the A/D conversion is completed or aborted, a
2T
AD Wait is required before the next acquisition can
be started. After this Wait, acquisition on the selected
channel is automatically started.
FIGURE 23-6: A/D CONVE RSION TAD CYCLES (ACQT<2:0> = 000, TACQ = 0)
FIGURE 23-7: A/D CONVE RSION TAD CYCLES (ACQT<2:0> = 010, TACQ = 4 TAD)
Note: The GO/DONE bit should NOT be set in
the same instruction that turns on the A/D.
TAD1 TAD2TAD3TAD4TAD5TAD6 TAD7TAD8TAD11
Set GO/DONE bit
Holding capacitor is disconnected from analog input (typically 100 ns)
T
AD9 TAD10
TCY - TAD
Next Q4: ADRESH:ADRESL is loaded, GO/DONE bit is cleared,
ADIF bit is set, holding capacitor is connected to analog input.
Conversion starts
b2
b11 b8 b7 b6 b5 b4 b3
b10 b9
TAD13TAD12
b0b1
1234567811
Set GO/DONE bit
(Holding capacitor is disconnected)
910
Next Q4: ADRESH:ADRESL is loaded, GO/DONE bit is cleared,
ADIF bit is set, holding capacitor is reconnected to analog input.
Conversion starts
123 4
(Holding capacitor continues
acquiring input)
TACQT Cycles TAD Cycles
Automatic
Acquisition
Time
b2b11 b8 b7 b6 b5 b4 b3
b10 b9
13
12
b0b1
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23.8 Use of the Special Event Triggers
A/D conversion can be started by the Special Event
Trigger of any of these modules:
• ECCP2 – Requires CCP2M<3:0> bits
(CCP2CON<3:0>) set at ‘1011’
• CTMU – Requires the setting of the CTTRIG bit
(CTMUCONH<0>)
•Timer1
•RTCC
To start an A/D conversion:
• The A/D module must be enabled (ADON = 1)
• The appropriate analog input channel selected
• The minimum acquisition period set one of these
ways:
- Timing provided by the user
- Selection made of an appropriate T
ACQ time
With these conditions met, the trigger sets the
GO/DONE bit and the A/D acquisition starts.
If the A/D module is not enabled (ADON = 0), the
module ignores the Special Event Trigger.
23.9 Operation in Power-Managed
Modes
The selection of the automatic acquisition time and A/D
conversion clock is determined in part by the clock
source and frequency while in a power-managed
mode.
If the A/D is expected to operate while the device is in
a power-managed mode, the ACQT<2:0> and
ADCS<2:0> bits in ADCON2 should be updated in
accordance with the power-managed mode clock that
will be used.
After the power-managed mode is entered (either of
the power-managed Run modes), an A/D acquisition or
conversion may be started. Once an acquisition or con-
version is started, the device should continue to be
clocked by the same power-managed mode clock
source until the conversion has been completed. If
desired, the device may be placed into the correspond-
ing power-managed Idle mode during the conversion.
If the power-managed mode clock frequency is less
than 1 MHz, the A/D RC clock source should be
selected.
Operation in Sleep mode requires that the A/D RC
clock be selected. If bits ACQT<2:0> are set to ‘000’
and a conversion is started, the conversion will be
delayed one instruction cycle to allow execution of the
SLEEP instruction and entry into Sleep mode. The
IDLEN and SCS<1:0> bits in the OSCCON register
must have already been cleared prior to starting the
conversion.
Note: With an ECCP2 trigger, Timer1 or Timer 3
is cleared. The timers reset to automati-
cally repeat the A/D acquisition period
with minimal software overhead (moving
ADRESH:ADRESL to the desired loca-
tion). If the A/D module is not enabled, the
Special Event Trigger is ignored by the
module, but the timer’s counter resets.
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TABLE 23-2: REGISTERS ASSOCIATED WITH A/D MODULE
Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
INTCON GIE/GIEH PEIE/GIEL TMR0IE INT0IE RBIE TMR0IF INT0IF RBIF
PIR1 PSPIF ADIF RC1IF TX1IF SSP1IF TMR1GIF TMR2IF TMR1IF
PIE1 PSPIE ADIE RC1IE TX1IE SSP1IE TMR1GIE TMR2IE TMR1IE
IPR1 PSPIP ADIP RC1IP TX1IP SSP1IP TMR1GIP TMR2IP TMR1IP
PIR3 TMR5GIF —RC2IF TX2IF CTMUIF CCP2IF CCP1IF RTCCIF
PIE3 TMR5GIE —RC2IE TX2IE CTMUIE CCP2IE CCP1IE RTCCIE
IPR3 TMR5GIP —RC2IP TX2IP CTMUIP CCP2IP CCP1IP RTCCIP
ADRESH A/D Result Register High Byte
ADRESL A/D Result Register Low Byte
ADCON0 — CHS4 CHS3 CHS2 CHS1 CHS0 GO/DONE ADON
ADCON1 TRIGSEL1 TRIGSEL0 VCFG1 VCFG0 VNCFG CHSN2 CHSN1 CHSN0
ADCON2 ADFM — ACQT2 ACQT1 ACQT0 ADCS2 ADCS1 ADCS0
ANCON0 ANSEL7 ANSEL6 ANSEL5 ANSEL4 ANSEL3 ANSEL2 ANSEL1 ANSEL0
ANCON1 ANSEL15 ANSEL14 ANSEL13 ANSEL12 ANSEL11 ANSEL10 ANSEL9 ANSEL8
ANCON2 ANSEL23 ANSEL22 ANSEL21 ANSEL20 ANSEL19 ANSEL18 ANSEL17 ANSEL16
CCP2CON P2M1 P2M0 DC2B1 DC2B0 CCP2M3 CCP2M2 CCP2M1 CCP2M0
PORTA RA7(2) RA6(2) RA5 RA4 RA3 RA2 RA1 RA0
TRISA TRISA7(2) TRISA6(2) TRISA5 TRISA4 TRISA3 TRISA2 TRISA1 TRISA0
PORTF RF7 RF6 RF5 RF4 RF3 RF2 RF1 —
TRISF TRISF7 TRISF6 TRISF5 TRISF4 TRISF3 TRISF2 TRISF1 —
PORTG — — RG5(3) RG4 RG3 RG2 RG1 RG0
TRISG — — — TRISG4 TRISG3 TRISG2 TRISG1 TRISG0
PORTH(1) RH7 RH6 RH5 RH4 RH3 RH2 RH1 RH0
TRISH(1) TRISH7 TRISH6 TRISH5 TRISH4 TRISH3 TRISH2 TRISH1 TRISH0
PMD0 CCP3MD CCP2MD CCP1MD UART2MD UART1MD SSP2MD SSP1MD ADCMD
Legend: — = unimplemented, read as ‘0’. Shaded cells are not used for A/D conversion.
Note 1: This register is not implemented on 64-pin devices.
2: These bits are available only in certain oscillator modes, when the FOSC2 Configuration bit = 0. If that
Configuration bit is cleared, this signal is not implemented.
3: Bit is available when Master Clear is disabled (MCLRE = 0). When MCLRE is set, the bit is unimplemented.
PIC18F87K22 FAMILY
DS39960C-page 366 2011 Microchip Technology Inc.
NOTES:
2011 Microchip Technology Inc. DS39960C-page 367
PIC18F87K22 FAMILY
24.0 COMPARATOR MODULE
The analog comparator module contains three compar-
ators that can be independently configured in a variety
of ways. The inputs can be selected from the analog
inputs and two internal voltage references. The digital
outputs are available at the pin level and can also be
read through the control register. Multiple output and
interrupt event generation are also available. A generic
single comparator from the module is shown in
Figure 24-1.
Key features of the module includes:
• Independent comparator control
• Programmable input configuration
• Output to both pin and register levels
• Programmable output polarity
• Independent interrupt generation for each
comparator with configurable interrupt-on-change
24.1 Registers
The CMxCON registers (CM1CON, CM2CON and
CM3CON) select the input and output configuration for
each comparator, as well as the settings for interrupt
generation (see Register 24-1).
The CMSTAT register (Register 24-2) provides the out-
put results of the comparators. The bits in this register
are read-only.
FIGURE 24-1: COMPARATOR SIMPLIFIED BLOCK DIAGRAM
Cx
VIN-
VIN+
COE CxOUT
0
1
2
3
0
1
CCH<1:0>
CxINB
CxINC(2)
C2INB/C2IND(1,2)
VBG
CxINA
CVREF
CON
Interrupt
Logic
EVPOL<1:0>
CMPxOUT
(CMSTAT<7:5>)
CMPxIF
CPOL
Polarity
Logic
CREF
Note 1: Comparators, 1 and 3, use C2INB as an input to the inverting terminal. Comparator 2 uses C2IND as an input to
the inverted terminal.
2: C1INC, C2INC and C2IND are all unavailable for 64-pin devices (PIC18F6XK22).
PIC18F87K22 FAMILY
DS39960C-page 368 2011 Microchip Technology Inc.
REGISTER 24-1: CMxCON: COMPARATOR CONTROL x REGISTER
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0
CON COE CPOL EVPOL1 EVPOL0 CREF CCH1 CCH0
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 CON: Comparator Enable bit
1 = Comparator is enabled
0 = Comparator is disabled
bit 6 COE: Comparator Output Enable bit
1 = Comparator output is present on the CxOUT pin
0 = Comparator output is internal only
bit 5 CPOL: Comparator Output Polarity Select bit
1 = Comparator output is inverted
0 = Comparator output is not inverted
bit 4-3 EVPOL<1:0>: Interrupt Polarity Select bits
11 = Interrupt generation on any change of the output(1)
10 = Interrupt generation only on high-to-low transition of the output
01 = Interrupt generation only on low-to-high transition of the output
00 = Interrupt generation is disabled
bit 2 CREF: Comparator Reference Select bit (non-inverting input)
1 = Non-inverting input connects to internal CVREF voltage
0 = Non-inverting input connects to CxINA pin
bit 1-0 CCH<1:0>: Comparator Channel Select bits
11 = Inverting input of comparator connects to VBG
10 = Inverting input of comparator connects to C2INB or C2IND pin(2,3)
01 = Inverting input of comparator connects to CxINC pin
00 = Inverting input of comparator connects to CxINB pin
Note 1: The CMPxIF bit is automatically set any time this mode is selected and must be cleared by the application
after the initial configuration.
2: Comparators, 1 and 3, use C2INB as an input to the inverting terminal. Comparator 2 uses C2IND.
3: C1INC, C2INC and C2IND are all unavailable for 64-pin devices (PIC18F6XK22).
2011 Microchip Technology Inc. DS39960C-page 369
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REGISTER 24-2: CMSTAT: COMPARATOR STATUS REGISTER
R-x R-x R-x U-0 U-0 U-0 U-0 U-0
CMP3OUT CMP2OUT CMP1OUT — — — — —
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7-5 CMP3OUT:CMP1OUT: Comparator x Status bits
If CPOL (CMxCON<5>)= 0 (non-inverted polarity):
1 = Comparator x’s VIN+ > VIN-
0 = Comparator x’s VIN+ < VIN-
If CPOL = 1 (inverted polarity):
1 = Comparator x’s VIN+ < VIN-
0 = Comparator x’s VIN+ > VIN-
bit 4-0 Unimplemented: Read as ‘0’
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DS39960C-page 370 2011 Microchip Technology Inc.
24.2 Comparator Operation
A single comparator is shown in Figure 24-2, along with
the relationship between the analog input levels and
the digital output. When the analog input at VIN+ is less
than the analog input, VIN-, the output of the compara-
tor is a digital low level. When the analog input at VIN+
is greater than the analog input, VIN-, the output of the
comparator is a digital high level. The shaded areas of
the output of the comparator in Figure 24-2 represent
the uncertainty due to input offsets and response time.
FIGURE 24-2: SI NGLE COMPARATOR
24.3 Comparator Response Time
Response time is the minimum time, after selecting a
new reference voltage or input source, before the com-
parator output has a valid level. The response time of
the comparator differs from the settling time of the volt-
age reference. Therefore, both of these times must be
considered when determining the total response to a
comparator input change; otherwise, the maximum
delay of the comparators should be used (see
Section 31.0 “Electrical Characteristics”).
24.4 Analog Input Connection
Considerations
A simplified circuit for an analog input is shown in
Figure 24-3. Since the analog pins are connected to a
digital output, they have reverse biased diodes to VDD
and VSS. The analog input, therefore, must be between
VSS and VDD. If the input voltage deviates from this
range by more than 0.6V in either direction, one of the
diodes is forward biased and a latch-up condition may
occur.
A maximum source impedance of 10 k is
recommended for the analog sources. Any external
component connected to an analog input pin, such as
a capacitor or a Zener diode, should have very little
leakage current.
FIGURE 24-3: COMPARATOR ANALOG INPUT MODEL
Output
VIN-
VIN+
–
+
VIN+
VIN-
Output
VA
RS
AIN
CPIN
5 pF
VDD
VT = 0.6V
VT = 0.6V
RIC
ILEAKAGE
±100 nA
VSS
Legend: CPIN = Input Capacitance
VT= Threshold Voltage
ILEAKAGE = Leakage Current at the pin due to various junctions
RIC = Interconnect Resistance
RS= Source Impedance
VA = Analog Voltage
Comparator
Input
<10k
2011 Microchip Technology Inc. DS39960C-page 371
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24.5 Comparator Control and
Configuration
Each comparator has up to eight possible combina-
tions of inputs: up to four external analog inputs and
one of two internal voltage references.
All of the comparators allow a selection of the signal
from pin, CxINA, or the voltage from the comparator
reference (CVREF) on the non-inverting channel. This is
compared to either CxINB, CxINC, C2INB/C2IND or
the microcontroller’s fixed internal reference voltage
(VBG, 1.024V nominal) on the inverting channel. The
comparator inputs and outputs are tied to fixed I/O pins,
defined in Table 24-1. The available comparator config-
urations and their corresponding bit settings are shown
in Figure 24-4.
TABLE 24-1: COMPARATOR INPUTS AND
OUTPUTS
24.5.1 COMPARATOR ENABLE AND
INPUT SELECTION
Setting the CON bit of the CMxCON register
(CMxCON<7>) enables the comparator for operation.
Clearing the CON bit disables the comparator, resulting
in minimum current consumption.
The CCH<1:0> bits in the CMxCON register
(CMxCON<1:0>) direct either one of three analog input
pins, or the Internal Reference Voltage (VBG), to the
comparator, VIN-. Depending on the comparator
operating mode, either an external or internal voltage
reference may be used. For external analog pins that
are unavailable in 64-pin devices (C1INC, C2INC and
C2IND), the corresponding configurations that use
them as inputs are unavailable.
The analog signal present at VIN- is compared to the
signal at VIN+ and the digital output of the comparator
is adjusted accordingly.
The external reference is used when CREF = 0
(CMxCON<2>) and VIN+ is connected to the CxINA
pin. When external voltage references are used, the
comparator module can be configured to have the
reference sources externally. The reference signal
must be between VSS and VDD and can be applied to
either pin of the comparator.
The comparator module also allows the selection of an
internally generated voltage reference (CVREF) from
the Comparator Voltage Reference module. This
module is described in more detail in Section 25.0
“Comparator Voltage Reference Module”. The
reference from the comparator voltage reference
module is only available when CREF = 1. In this mode,
the internal voltage reference is applied to the
comparator’s VIN+ pin.
24.5.2 COMPARATOR ENABLE AND
OUTPUT SELECTION
The comparator outputs are read through the CMSTAT
register. The CMSTAT<5> bit reads the Comparator 1
output, CMSTAT<6> reads Comparator 2 output and
CMSTAT<7> reads Comparator 3 output. These bits
are read-only.
The comparator outputs may also be directly output to
the RF2, RF1 and RG1 I/O pins by setting the COE bit
(CMxCON<6>). When enabled, multiplexers in the
output path of the pins switch to the output of the com-
parator. While in this mode, the TRISF<2:1> and
TRISG<1> bits still function as the digital output enable
bits for the RF2, RF1 and RG1 pins.
By default, the comparator’s output is at logic high
whenever the voltage on VIN+ is greater than on VIN-.
The polarity of the comparator outputs can be inverted
using the CPOL bit (CMxCON<5>).
The uncertainty of each of the comparators is related to
the input offset voltage and the response time given in
the specifications, as discussed in Section 24.2
“Comp arator Operation”.
Comparator Input or Output I/O Pin
1
C1INA (VIN+) RF6
C1INB (VIN-) RF5
C1INC(1) (VIN-) RH6
C2INB (VIN-) RF3
C1OUT RF2
2
C2INA (VIN+) RF4
C2INB (VIN-) RF3
C2INC(1) (VIN-) RH4
C2IND(1) (VIN-) RH5
C2OUT RF1
3
C3INA (VIN+) RG2
C3INB (VIN-) RG3
C3INC (VIN-) RG4
C2INB (VIN-) RF3
C3OUT RG1
Note 1: C1INC, C2INC and C2IND are all
unavailable for 64-pin devices
(PIC18F6XK22).
Note: The comparator input pin selected by
CCH<1:0> must be configured as an input
by setting both the corresponding TRISF,
TRISG or TRISH bit and the corresponding
ANSELx bit in the ANCONx register.
PIC18F87K22 FAMILY
DS39960C-page 372 2011 Microchip Technology Inc.
FIGURE 24-4: COMPARATOR CONFIGURATIONS
Cx
VIN-
VIN+Off (Read as ‘0’)
Comparator Off
CON = 0, CREF = x, CCH<1:0> = xx COE
Cx
VIN-
VIN+
COE
Comparator CxINB > CxINA Compare
CON = 1, CREF = 0, CCH<1:0> = 00
CxINB
CxINA Cx
VIN-
VIN+
COE
Comparator CxINC > CxINA Compare(2,3)
CON = 1, CREF = 0, CCH<1:0> = 01
CxINC
CxINA
Cx
VIN-
VIN+
COE
Comparator CxIND > CxINA Compare(3)
CON = 1, CREF = 0, CCH<1:0> = 10
C2INB/
CxINA
Cx
VIN-
VIN+
COE
Comparator VIRV > CxINA Compare
CON = 1, CREF = 0, CCH<1:0> = 11
VBG(1)
CxINA
Cx
VIN-
VIN+
COE
Comparator CxINB > CVREF Compare
CON = 1, CREF = 1, CCH<1:0> = 00
CxINB
CVREF Cx
VIN-
VIN+
COE
Comparator CxINC > CVREF Compare(2,3)
CON = 1, CREF = 1, CCH<1:0> = 01
CxINC
CVREF
Cx
VIN-
VIN+
COE
Comparator CxIND > CVREF Compare(3)
CON = 1, CREF = 1, CCH<1:0> = 10
CVREF
Cx
VIN-
VIN+
COE
Pin
Comparator VIRV > CVREF Compare
CON = 1, CREF = 1, CCH<1:0> = 11
VBG(1)
CVREF CxOUT
Note 1: VBG is the Internal Reference Voltage (1.024V nominal).
2: Configuration is unavailable for CM1CON on 64-pin devices (PIC18F6XK22).
3: Configuration is unavailable for CM2CON on 64-pin devices (PIC18F6XK22).
Pin
CxOUT
Pin
CxOUT
Pin
CxOUT
Pin
CxOUT
Pin
CxOUT
Pin
CxOUT
Pin
CxOUT
Pin
CxOUT
C2IND
C2INB/
C2IND
2011 Microchip Technology Inc. DS39960C-page 373
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24.6 Comparator Interrupts
The comparator interrupt flag is set whenever any of
the following occurs:
• Low-to-high transition of the comparator output
• High-to-low transition of the comparator output
• Any change in the comparator output
The comparator interrupt selection is done by the
EVPOL<1:0> bits in the CMxCON register
(CMxCON<4:3>).
In order to provide maximum flexibility, the output of the
comparator may be inverted using the CPOL bit in the
CMxCON register (CMxCON<5>). This is functionally
identical to reversing the inverting and non-inverting
inputs of the comparator for a particular mode.
An interrupt is generated on the low-to-high or high-to-
low transition of the comparator output. This mode of
interrupt generation is dependent on EVPOL<1:0> in
the CMxCON register. When EVPOL<1:0> = 01 or 10,
the interrupt is generated on a low-to-high or high-to-
low transition of the comparator output. Once the
interrupt is generated, it is required to clear the interrupt
flag by software.
When EVPOL<1:0> = 11, the comparator interrupt flag
is set whenever there is a change in the output value of
either comparator. Software will need to maintain
information about the status of the output bits, as read
from CMSTAT<7:5>, to determine the actual change
that occurred.
The CMPxIF bits (PIR6<2:0>) are the Comparator
Interrupt Flags. The CMPxIF bits must be reset by
clearing them. Since it is also possible to write a ‘1’ to
this register, a simulated interrupt may be initiated.
Table 24-2 shows the interrupt generation with respect
to comparator input voltages and EVPOL bit settings.
Both the CMPxIE bits (PIE6<2:0>) and the PEIE bit
(INTCON<6>) must be set to enable the interrupt. In
addition, the GIE bit (INTCON<7>) must also be set. If
any of these bits are clear, the interrupt is not enabled,
though the CMPxIF bits will still be set if an interrupt
condition occurs.
A simplified diagram of the interrupt section is shown in
Figure 24-3.
TABLE 24-2: COMPARATOR INTERRUPT GENERATION
Note: CMPxIF bits will not be set when
EVPOL<1:0> = 00.
CPOL EVPOL<1:0> Comparator
Input Change CxOUT Transition Interrupt
Generated
0
00 VIN+ > VIN- Low-to-High No
VIN+ < VIN-High-to-Low No
01 VIN+ > VIN- Low-to-High Yes
VIN+ < VIN-High-to-Low No
10 VIN+ > VIN- Low-to-High No
VIN+ < VIN-High-to-Low Yes
11 VIN+ > VIN- Low-to-High Yes
VIN+ < VIN-High-to-Low Yes
1
00 VIN+ > VIN-High-to-Low No
VIN+ < VIN- Low-to-High No
01 VIN+ > VIN-High-to-Low No
VIN+ < VIN- Low-to-High Yes
10 VIN+ > VIN-High-to-Low Yes
VIN+ < VIN- Low-to-High No
11 VIN+ > VIN-High-to-Low Yes
VIN+ < VIN- Low-to-High Yes
PIC18F87K22 FAMILY
DS39960C-page 374 2011 Microchip Technology Inc.
24.7 Comparator Operation
During Sleep
When a comparator is active and the device is placed
in Sleep mode, the comparator remains active and the
interrupt is functional, if enabled. This interrupt will
wake-up the device from Sleep mode, when enabled.
Each operational comparator will consume additional
current.
To minimize power consumption while in Sleep mode,
turn off the comparators (CON = 0) before entering
Sleep. If the device wakes up from Sleep, the contents
of the CMxCON register are not affected.
24.8 Effect s of a Reset
A device Reset forces the CMxCON registers to their
Reset state. This forces both comparators and the
voltage reference to the OFF state.
TABLE 24-3: REGISTERS ASSOCIATED WITH COMPARATOR MODULE
Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
INTCON GIE/GIEH PEIE/GIEL TMR0IE INT0IE RBIE TMR0IF INT0IF RBIF
PIR6 — — — EEIF — CMP3IF CMP2IF CMP1IF
PIE6 — — — EEIE — CMP3IE CMP2IE CMP1IE
IPR6 — — — EEIP — CMP3IP CMP2IP CMP1IP
CM1CON CON COE CPOL EVPOL1 EVPOL0 CREF CCH1 CCH0
CM2CON CON COE CPOL EVPOL1 EVPOL0 CREF CCH1 CCH0
CM3CON CON COE CPOL EVPOL1 EVPOL0 CREF CCH1 CCH0
CVRCON CVREN CVROE CVRSS CVR4 CVR3 CVR2 CVR1 CVR0
CMSTAT CMP3OUT CMP2OUT CMP1OUT —————
PORTF RF7 RF6 RF5 RF4 RF3 RF2 RF1 —
LATF LATF7 LATF6 LATF5 LATF4 LATF3 LATF2 LATF1 —
TRISF TRISF7 TRISF6 TRISF5 TRISF4 TRISF3 TRISF2 TRISF1 —
PORTG — — RG5(1) RG4 RG3 RG2 RG1 RG0
LATG — — — LATG4 LATG3 LATG2 LATG1 LATG0
TRISG — — — TRISG4 TRISG3 TRISG2 TRISG1 TRISG0
PORTH RH7 RH6 RH5 RH4 RH3 RH2 RH1 RH0
LATH LATH7 LATH6 LATH5 LATH4 LATH3 LATH2 LATH1 LATH0
TRISH TRISH7 TRISH6 TRISH5 TRISH4 TRISH3 TRISH2 TRISH1 TRISH0
ANCON0 ANSEL7 ANSEL6 ANSEL5 ANSEL4 ANSEL3 ANSEL2 ANSEL1 ANSEL0
ANCON1 ANSEL15 ANSEL14 ANSEL13 ANSEL12 ANSEL11 ANSEL10 ANSEL9 ANSEL8
ANCON2 ANSEL23 ANSEL22 ANSEL21 ANSEL20 ANSEL19 ANSEL18 ANSEL17 ANSEL16
PMD0 CCP3MD CCP2MD CCP1MD UART2MD UART1MD SSP2MD SSP1MD ADCMD
Legend: — = unimplemented, read as ‘0’.
Note 1: Bit is available when Master Clear is disabled (MCLRE = 0). When MCLRE is set, the bit is unimplemented.
2011 Microchip Technology Inc. DS39960C-page 375
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25.0 COMPARATOR VOLTAGE
REFERENC E MODULE
The comparator voltage reference is a 32-tap resistor
ladder network that provides a selectable reference
voltage. Although its primary purpose is to provide a
reference for the analog comparators, it may also be
used independently of them.
A block diagram of the module is shown in Figure 25-1.
The resistor ladder is segmented to provide a range of
CVREF values and has a power-down function to
conserve power when the reference is not being used.
The module’s supply reference can be provided from
either device VDD/VSS or an external voltage reference.
25.1 Configuring the Comp arator
Voltage Reference
The comparator voltage reference module is controlled
through the CVRCON register (Register 25-1). The
comparator voltage reference provides a range of
output voltage with 32 levels.
The CVR<4:0> selection bits (CVRCON<4:0>) offer a
range of output voltages. Equation 25-1 shows the how
the comparator voltage reference is computed.
EQUATION 25-1:
The comparator reference supply voltage can come
from either VDD and VSS, or the external VREF+ and
VREF- that are multiplexed with RA3 and RA2. The
voltage source is selected by the CVRSS bit
(CVRCON<5>).
The settling time of the comparator voltage reference
must be considered when changing the CVREF
output (see Table 31-2 in Section 31.0 “Electrical
Characteristics”).
CVREF = (VREF-) + (CVR<4:0>/32) • (VREF+ – VREF-)
If CVRSS = 1:
CVREF = (AVSS) + (CVR<4:0>/32) • (AVDD – AVSS)
If CVRSS = 0:
REGISTER 25-1: CVRCON: COMPARATOR VOLTAGE REFERENCE CONTROL REGISTER
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0
CVREN CVROE CVRSS CVR4 CVR3 CVR2 CVR1 CVR0
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 CVREN: Comparator Voltage Reference Enable bit
1 =CVREF circuit is powered on
0 =CVREF circuit is powered down
bit 6 CVROE: Comparator VREF Output Enable bit
1 =CVREF voltage level is output on CVREF pin
0 =CVREF voltage level is disconnected from CVREF pin
bit 5 CVRSS: Comparator VREF Source Selection bit
1 = Comparator reference source, CVRSRC = VREF+–VREF-
0 = Comparator reference source, CVRSRC = AVDD –AVSS
bit 4-0 CVR<4:0>: Comparator VREF Value Selection 0 CVR<4:0> 31 bits
When CVRSS = 1:
CVREF = (VREF-) + (CVR<4:0>/32) (VREF+ – VREF-)
When CVRSS = 0:
CVREF = (AVSS) + (CVR<4:0>/32) (AVDD – AVSS)
PIC18F87K22 FAMILY
DS39960C-page 376 2011 Microchip Technology Inc.
FIGURE 25-1: COMPARATOR VOLTAGE REFERENCE BLOCK DIAGRAM
25.2 Voltage Reference Accuracy/Error
The full range of voltage reference cannot be realized
due to the construction of the module. The transistors
on the top and bottom of the resistor ladder network
(Figure 25-1) keep CVREF from approaching the refer-
ence source rails. The voltage reference is derived
from the reference source; therefore, the CVREF output
changes with fluctuations in that source. The tested
absolute accuracy of the voltage reference can be
found in Section 31.0 “Electrical Characteristics”.
25.3 Operation During Sleep
When the device wakes up from Sleep through an
interrupt or a Watchdog Timer time-out, the contents of
the CVRCON register are not affected. To minimize
current consumption in Sleep mode, the voltage
reference should be disabled.
25.4 Effect s of a Reset
A device Reset disables the voltage reference by
clearing bit, CVREN (CVRCON<7>). This Reset also
disconnects the reference from the RF5 pin by clearing
bit, CVROE (CVRCON<6>).
25.5 Connection Considerations
The voltage reference module operates independently
of the comparator module. The output of the reference
generator may be connected to the RF5 pin if the
CVROE bit is set. Enabling the voltage reference out-
put onto RF5 when it is configured as a digital input will
increase current consumption. Connecting RF5 as a
digital output with CVRSS enabled will also increase
current consumption.
The RF5 pin can be used as a simple D/A output with
limited drive capability. Due to the limited current drive
capability, a buffer must be used on the voltage
reference output for external connections to VREF.
Figure 25-2 shows an example buffering technique.
32-to-1 MUX
CVR<4:0>
R
CVREN
CVRSS = 0
AVDD
VREF+CVRSS = 1
R
R
R
R
R
R
32 Steps CVREF
VREF-
CVRSS = 1
CVRSS = 0
2011 Microchip Technology Inc. DS39960C-page 377
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FIGURE 25-2: COMPARATOR VOLTAGE REFERENCE OUTPUT BUFFER EXAMPLE
TABLE 25-1: REGISTERS ASSOCIATED WITH COMPARATOR VOLTAGE REFERENCE
Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
CVRCON CVREN CVROE CVRSS CVR4 CVR3 CVR2 CVR1 CVR0
CM1CON CON COE CPOL EVPOL1 EVPOL0 CREF CCH1 CCH0
CM2CON CON COE CPOL EVPOL1 EVPOL0 CREF CCH1 CCH0
CM3CON CON COE CPOL EVPOL1 EVPOL0 CREF CCH1 CCH0
TRISF TRISF7 TRISF6 TRISF5 TRISF4 TRISF3 TRISF2 TRISF1 —
TRISA TRISA7 TRISA6 TRISA5 TRISA4 TRISA3 TRISA2 TRISA1 TRISA0
ANCON0 ANSEL7 ANSEL6 ANSEL5 ANSEL4 ANSEL3 ANSEL2 ANSEL1 ANSEL0
ANCON1 ANSEL15 ANSEL14 ANSEL13 ANSEL12 ANSEL11 ANSEL10 ANSEL9 ANSEL8
Legend: — = unimplemented, read as ‘0’. Shaded cells are not used with the comparator voltage reference.
CVREF Output
+
–
CVREF
Module
Voltage
Reference
Output
Impedance
R(1)
PIC18F87K22
Note 1: R is dependent upon the Voltage Reference Configuration bits, CVRCON<3:0> and CVRCON<5>.
RF5
PIC18F87K22 FAMILY
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NOTES:
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PIC18F87K22 FAMILY
26.0 HIGH/LOW-VOLTAGE DETECT
(HLVD)
The PIC18F87K22 family of devices has a High/Low-
Voltage Detect module (HLVD). This is a programmable
circuit that sets both a device voltage trip point and the
direction of change from that point. If the device experi-
ences an excursion past the trip point in that direction, an
interrupt flag is set. If the interrupt is enabled, the pro-
gram execution branches to the interrupt vector address
and the software responds to the interrupt.
The High/Low-Voltage Detect Control register
(Register 26-1) completely controls the operation of the
HLVD module. This allows the circuitry to be “turned
off” by the user under software control, which
minimizes the current consumption for the device.
The module’s block diagram is shown in Figure 26-1.
REGISTER 26-1: HLVDCON: HIGH/LOW-VOLTAGE DETECT CONTROL REGISTER
R/W-0 R-0 R-0 R/W-0 R/W-0 R/W-1 R/W-0 R/W-0
VDIRMAG BGVST IRVST HLVDEN HLVDL3(1) HLVDL2(1) HLVDL1(1) HLVDL0(1)
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 VDIRMAG: Voltage Direction Magnitude Select bit
1 = Event occurs when voltage equals or exceeds trip point (HLVDL<3:0>)
0 = Event occurs when voltage equals or falls below trip point (HLVDL<3:0>)
bit 6 BGVST: Band Gap Reference Voltages Stable Status Flag bit
1 = Internal band gap voltage references are stable
0 = Internal band gap voltage references are not stable
bit 5 IRVST: Internal Reference Voltage Stable Flag bit
1 = Indicates that the voltage detect logic will generate the interrupt flag at the specified voltage range
0 = Indicates that the voltage detect logic will not generate the interrupt flag at the specified voltage
range and the HLVD interrupt should not be enabled
bit 4 HLVDEN: High/Low-Voltage Detect Power Enable bit
1 = HLVD is enabled
0 = HLVD is disabled
bit 3-0 HLVDL<3:0>: Voltage Detection Limit bits(1)
1111 = External analog input is used (input comes from the HLVDIN pin)
1110 = Maximum setting
.
.
.
0000 = Minimum setting
Note 1: For the electrical specifications, see Parameter D420.
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The module is enabled by setting the HLVDEN bit
(HLVDCON<4>). Each time the HLVD module is
enabled, the circuitry requires some time to stabilize.
The IRVST bit (HLVDCON<5>) is a read-only bit used
to indicate when the circuit is stable. The module can
only generate an interrupt after the circuit is stable and
IRVST is set.
The VDIRMAG bit (HLVDCON<7>) determines the
overall operation of the module. When VDIRMAG is
cleared, the module monitors for drops in VDD below a
predetermined set point. When the bit is set, the
module monitors for rises in VDD above the set point.
26.1 Operation
When the HLVD module is enabled, a comparator uses
an internally generated reference voltage as the set
point. The set point is compared with the trip point,
where each node in the resistor divider represents a
trip point voltage. The “trip point” voltage is the voltage
level at which the device detects a high or low-voltage
event, depending on the configuration of the module.
When the supply voltage is equal to the trip point, the
voltage tapped off of the resistor array is equal to the
internal reference voltage generated by the voltage
reference module. The comparator then generates an
interrupt signal by setting the HLVDIF bit.
The trip point voltage is software programmable to any of
16 values. The trip point is selected by programming the
HLVDL<3:0> bits (HLVDCON<3:0>).
The HLVD module has an additional feature that allows
the user to supply the trip voltage to the module from an
external source. This mode is enabled when bits,
HLVDL<3:0>, are set to ‘1111’. In this state, the
comparator input is multiplexed from the external input
pin, HLVDIN. This gives users the flexibility of configur-
ing the High/Low-Voltage Detect interrupt to occur at
any voltage in the valid operating range.
FIGURE 26-1: HLVD MODULE BLOCK DIAGRAM (WITH EXTERNAL INPUT)
Set
VDD
16-to-1 MUX
HLVDEN
HLVDCON
HLVDL<3:0> Register
HLVDIN
VDD
Externally Generated
Trip Point
HLVDIF
HLVDEN
BOREN
Internal Voltage
Reference
VDIRMAG
1.024V Typical
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26.2 HLVD Setup
To set up the HLVD module:
1. Select the desired HLVD trip point by writing the
value to the HLVDL<3:0> bits.
2. Set the VDIRMAG bit to detect high voltage
(VDIRMAG = 1) or low voltage (VDIRMAG = 0).
3. Enable the HLVD module by setting the
HLVDEN bit.
4. Clear the HLVD interrupt flag (PIR2<2>), which
may have been set from a previous interrupt.
5. If interrupts are desired, enable the HLVD inter-
rupt by setting the HLVDIE and GIE bits
(PIE2<2> and INTCON<7>, respectively).
An interrupt will not be generated until the
IRVST bit is set.
26.3 Current Consumption
When the module is enabled, the HLVD comparator
and voltage divider are enabled and consume static
current. The total current consumption, when enabled,
is specified in electrical specification Parameter D022B
(Table 31-13).
Depending on the application, the HLVD module does
not need to operate constantly. To reduce current
requirements, the HLVD circuitry may only need to be
enabled for short periods where the voltage is checked.
After such a check, the module could be disabled.
26.4 HLVD Start-up Time
The internal reference voltage of the HLVD module,
specified in electrical specification Parameter 37
(Section 31.0 “Electrical Characteristics”), may be
used by other internal circuitry, such as the
programmable Brown-out Reset. If the HLVD or other
circuits using the voltage reference are disabled to
lower the device’s current consumption, the reference
voltage circuit will require time to become stable before
a low or high-voltage condition can be reliably
detected. This start-up time, TIRVST, is an interval that
is independent of device clock speed. It is specified in
electrical specification Parameter 37 (Table 31-13).
The HLVD interrupt flag is not enabled until TIRVST has
expired and a stable reference voltage is reached. For
this reason, brief excursions beyond the set point may
not be detected during this interval (see Figure 26-2 or
Figure 26-3).
Note: Before changing any module settings
(VDIRMAG, LVDL<3:0>), first disable the
module (LVDEN = 0), make the changes
and re-enable the module. This prevents
the generation of false HLVD events.
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FIGURE 26-2: LOW-VOLTAGE DETECT OPERATION (VDIRMAG = 0)
VHLVD
VDD
HLVDIF
VHLVD
VDD
Enable HLVD
TIRVST
HLVDIF may not be Set
Enable HLVD
HLVDIF
HLVDIF Cleared in Software
HLVDIF Cleared in Software
HLVDIF Cleared in Software,
CASE 1:
CASE 2:
HLVDIF Remains Set since HLVD Condition still Exists
TIRVST
Internal Reference is Stable
Internal Reference is Stable
IRVST
IRVST
2011 Microchip Technology Inc. DS39960C-page 383
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FIGURE 26-3: HIGH-VOLTAGE DETECT OPERATION (VDIRMAG = 1)
26.5 Applications
In many applications, it is desirable to detect a drop
below, or rise above, a particular voltage threshold. For
example, the HLVD module could be periodically
enabled to detect Universal Serial Bus (USB) attach or
detach. This assumes the device is powered by a lower
voltage source than the USB when detached. An attach
would indicate a high-voltage detect from, for example,
3.3V to 5V (the voltage on USB) and vice versa for a
detach. This feature could save a design a few extra
components and an attach signal (input pin).
For general battery applications, Figure 26-4 shows a
possible voltage curve. Over time, the device voltage
decreases. When the device voltage reaches voltage,
VA, the HLVD logic generates an interrupt at time, TA.
The interrupt could cause the execution of an ISR,
which would allow the application to perform “house-
keeping tasks” and a controlled shutdown before the
device voltage exits the valid operating range at TB.
This would give the application a time window, repre-
sented by the difference between TA and TB, to safely
exit.
FIGURE 26-4: TYPICAL LOW-VOLTAGE
DETECT APPLICATION
VHLVD
VDD
HLVDIF
VHLVD
VDD
Enable HLVD
TIRVST
HLVDIF may not be Set
Enable HLVD
HLVDIF
HLVDIF Cleared in Software
HLVDIF Cleared in Software
HLVDIF Cleared in Software,
CASE 1:
CASE 2:
HLVDIF Remains Set since HLVD Condition still Exists
TIRVST
IRVST
Internal Reference is Stable
Internal Reference is Stable
IRVST
Time
Voltage
VA
VB
TATB
VA = HLVD trip point
VB = Minimum valid device
operating voltage
Legend:
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26.6 Operation During Sleep
When enabled, the HLVD circuitry continues to operate
during Sleep. If the device voltage crosses the trip
point, the HLVDIF bit will be set and the device will
wake-up from Sleep. Device execution will continue
from the interrupt vector address if interrupts have
been globally enabled.
26.7 Effects of a Reset
A device Reset forces all registers to their Reset state.
This forces the HLVD module to be turned off.
TABLE 26-1: REGISTERS ASSOCIATED WITH HIGH/LOW-VOLTAGE DETECT MODULE
Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
HLVDCON VDIRMAG BGVST IRVST HLVDEN HLVDL3 HLVDL2 HLVDL1 HLVDL0
INTCON GIE/GIEH PEIE/GIEL TMR0IE INT0IE RBIE TMR0IF INT0IF RBIF
PIR2 OSCFIF —SSP2IF BLC2IF BCL1IF HLVDIF TMR3IF TMR3GIF
PIE2 OSCFIE —SSP2IE BLC2IE BCL1IE HLVDIE TMR3IE TMR3GIE
IPR2 OSCFIP —SSP2IP BLC2IP BCL1IP HLVDIP TMR3IP TMR3GIP
TRISA TRISA7(1) TRISA6(1) TRISA5 TRISA4 TRISA3 TRISA2 TRISA1 TRISA0
ANCON0 ANSEL7 ANSEL6 ANSEL5 ANSEL4 ANSEL3 ANSEL2 ANSEL1 ANSEL0
Legend: — = unimplemented, read as ‘0’. Shaded cells are unused by the HLVD module.
Note 1: PORTA<7:6> and their direction bits are individually configured as port pins based on various primary
oscillator modes. When disabled, these bits read as ‘0’.
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27.0 CHARGE TIME
MEASUREMENT UNIT (CTMU)
The Charge Time Measurement Unit (CTMU) is a
flexible analog module that provides accurate differen-
tial time measurement between pulse sources, as well
as asynchronous pulse generation. By working with
other on-chip analog modules, the CTMU can precisely
measure time, capacitance and relative changes in
capacitance or generate output pulses with a specific
time delay. The CTMU is ideal for interfacing with
capacitive-based sensors.
The module includes these key features:
• Up to 24 channels available for capacitive or time
measurement input
• On-chip precision current source
• Four-edge input trigger sources
• Polarity control for each edge source
• Control of edge sequence
• Control of response to edges
• Time measurement resolution of 1 nanosecond
• High-precision time measurement
• Time delay of external or internal signal
asynchronous to system clock
• Accurate current source suitable for capacitive
measurement
The CTMU works in conjunction with the A/D Converter
to provide up to 24 channels for time or charge
measurement, depending on the specific device and
the number of A/D channels available. When config-
ured for time delay, the CTMU is connected to one of
the analog comparators. The level-sensitive input edge
sources can be selected from four sources: two
external inputs or the ECCP1/ECCP2 Special Event
Triggers.
The CTMU special event can trigger the Analog-to-Digital
Converter module.
Figure 27-1 provides a block diagram of the CTMU.
FIGURE 27-1: CTMU BLOCK DIAGRAM
CTED1
CTED2
Current Source
Edge
Control
Logic
CTMUCON
Pulse
Generator
A/D Converter Comparator 2
Input
ECCP2
ECCP1
Current
Control
ITRIM<5:0>
IRNG<1:0>
CTMUICON
CTMU
Control
Logic
EDGEN
EDGSEQEN
EDG1SELx
EDG1POL
EDG2SELx
EDG2POL
EDG1STAT
EDG2STAT
TGEN
IDISSEN
CTTRIG
A/D Trigger
CTPLS
Comparator 2 Output
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27.1 CTMU Registers
The control registers for the CTMU are:
• CTMUCONH
• CTMUCONL
• CTMUICON
The CTMUCONH and CTMUCONL registers
(Register 27-1 and Register 27-2) contain control bits
for configuring the CTMU module edge source selec-
tion, edge source polarity selection, edge sequencing,
A/D trigger, analog circuit capacitor discharge and
enables. The CTMUICON register (Register 27-3) has
bits for selecting the current source range and current
source trim.
REGISTER 27-1: CTMUCONH: CTMU CONTROL HIGH REGISTER
R/W-0 U-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0
CTMUEN — CTMUSIDL TGEN EDGEN EDGSEQEN IDISSEN CTTRIG
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 CTMUEN: CTMU Enable bit
1 = Module is enabled
0 = Module is disabled
bit 6 Unimplemented: Read as ‘0’
bit 5 CTMUSIDL: Stop in Idle Mode bit
1 = Discontinue module operation when device enters Idle mode
0 = Continue module operation in Idle mode
bit 4 TGEN: Time Generation Enable bit
1 = Enables edge delay generation
0 = Disables edge delay generation
bit 3 EDGEN: Edge Enable bit
1 = Edges are not blocked
0 = Edges are blocked
bit 2 EDGSEQEN: Edge Sequence Enable bit
1 = Edge 1 event must occur before Edge 2 event can occur
0 = No edge sequence is needed
bit 1 IDISSEN: Analog Current Source Control bit
1 = Analog current source output is grounded
0 = Analog current source output is not grounded
bit 0 CTTRIG: Trigger Control bit
1 = Trigger output is enabled
0 = Trigger output is disabled
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REGISTER 27-2: CTMUCONL: CTMU CONTROL LOW REGISTER
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0
EDG2POL EDG2SEL1 EDG2SEL0 EDG1POL EDG1SEL1 EDG1SEL0 EDG2STAT EDG1STAT
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 EDG2POL: Edge 2 Polarity Select bit
1 = Edge 2 is programmed for a positive edge response
0 = Edge 2 is programmed for a negative edge response
bit 6-5 EDG2SEL<1:0>: Edge 2 Source Select bits
11 = CTED1 pin
10 = CTED2 pin
01 = ECCP1 Special Event Trigger
00 = ECCP2 Special Event Trigger
bit 4 EDG1POL: Edge 1 Polarity Select bit
1 = Edge 1 is programmed for a positive edge response
0 = Edge 1 is programmed for a negative edge response
bit 3-2 EDG1SEL<1:0>: Edge 1 Source Select bits
11 = CTED1 pin
10 = CTED2 pin
01 = ECCP1 Special Event Trigger
00 = ECCP2 Special Event Trigger
bit 1 EDG2STAT: Edge 2 Status bit
1 = Edge 2 event has occurred
0 = Edge 2 event has not occurred
bit 0 EDG1STAT: Edge 1 Status bit
1 = Edge 1 event has occurred
0 = Edge 1 event has not occurred
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REGISTER 27-3: CTMUICON: CTMU CURRENT CONTROL REGISTER
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0
ITRIM5 ITRIM4 ITRIM3 ITRIM2 ITRIM1 ITRIM0 IRNG1 IRNG0
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7-2 ITRIM<5:0>: Current Source Trim bits
011111 = Maximum positive change from nominal current
011110
.
.
.
000001 = Minimum positive change from nominal current
000000 = Nominal current output specified by IRNG<1:0>
111111 = Minimum negative change from nominal current
.
.
.
100010
100001 = Maximum negative change from nominal current
bit 1-0 IRNG<1:0>: Current Source Range Select bits
11 = 100 x Base Current
10 = 10 x Base Current
01 = Base Current Level (0.55 A nominal)
00 = Current Source Disabled
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27.2 CTMU Operation
The CTMU works by using a fixed current source to
charge a circuit. The type of circuit depends on the type
of measurement being made.
In the case of charge measurement, the current is fixed
and the amount of time the current is applied to the cir-
cuit is fixed. The amount of voltage read by the A/D
becomes a measurement of the circuit’s capacitance.
In the case of time measurement, the current, as well
as the capacitance of the circuit, is fixed. In this case,
the voltage read by the A/D is representative of the
amount of time elapsed from the time the current
source starts and stops charging the circuit.
If the CTMU is being used as a time delay, both capaci-
tance and current source are fixed, as well as the voltage
supplied to the comparator circuit. The delay of a signal
is determined by the amount of time it takes the voltage
to charge to the comparator threshold voltage.
27.2.1 THEORY OF OPERATION
The operation of the CTMU is based on the equation
for charge:
More simply, the amount of charge measured in
coulombs in a circuit is defined as current in amperes
(I) multiplied by the amount of time in seconds that the
current flows (t). Charge is also defined as the capaci-
tance in farads (C) multiplied by the voltage of the
circuit (V). It follows that:
The CTMU module provides a constant, known current
source. The A/D Converter is used to measure (V) in
the equation, leaving two unknowns: capacitance (C)
and time (t). The above equation can be used to calcu-
late capacitance or time, by either the relationship
using the known fixed capacitance of the circuit:
or by:
using a fixed time that the current source is applied to
the circuit.
27.2.2 CURRENT SOURCE
At the heart of the CTMU is a precision current source,
designed to provide a constant reference for measure-
ments. The level of current is user-selectable across
three ranges or a total of two orders of magnitude, with
the ability to trim the output in ±2% increments
(nominal). The current range is selected by the
IRNG<1:0> bits (CTMUICON<1:0>), with a value of
‘00’ representing the lowest range.
Current trim is provided by the ITRIM<5:0> bits
(CTMUICON<7:2>). These six bits allow trimming of
the current source in steps of approximately 2% per
step. Half of the range adjusts the current source posi-
tively and the other half reduces the current source. A
value of ‘000000’ is the neutral position (no change). A
value of ‘100000’ is the maximum negative adjustment
(approximately -62%) and ‘011111’ is the maximum
positive adjustment (approximately +62%).
27.2.3 EDGE SELECTION AND CONTROL
CTMU measurements are controlled by edge events
occurring on the module’s two input channels. Each
channel, referred to as Edge 1 and Edge 2, can be con-
figured to receive input pulses from one of the edge
input pins (CTED1 and CTED2) or CCPx Special Event
Triggers. The input channels are level-sensitive,
responding to the instantaneous level on the channel
rather than a transition between levels. The inputs are
selected using the EDG1SEL and EDG2SEL bit pairs
(CTMUCONL<3:2, 6:5>).
In addition to source, each channel can be configured for
event polarity using the EDGE2POL and EDGE1POL
bits (CTMUCONL<7,4>). The input channels can also
be filtered for an edge event sequence (Edge 1 occur-
ring before Edge 2) by setting the EDGSEQEN bit
(CTMUCONH<2>).
27.2.4 EDGE STATUS
The CTMUCON register also contains two status bits,
EDG2STAT and EDG1STAT (CTMUCONL<1:0>).
Their primary function is to show if an edge response
has occurred on the corresponding channel. The
CTMU automatically sets a particular bit when an edge
response is detected on its channel. The level-sensitive
nature of the input channels also means that the status
bits become set immediately if the channel’s configura-
tion is changed and matches the channel’s current
state.
The module uses the edge status bits to control the cur-
rent source output to external analog modules (such as
the A/D Converter). Current is only supplied to external
modules when only one (not both) of the status bits is
set. Current is shut off when both bits are either set or
cleared. This allows the CTMU to measure current only
during the interval between edges. After both status
bits are set, it is necessary to clear them before another
measurement is taken. Both bits should be cleared
simultaneously, if possible, to avoid re-enabling the
CTMU current source.
In addition to being set by the CTMU hardware, the
edge status bits can also be set by software. This per-
mits a user application to manually enable or disable
the current source. Setting either (but not both) of the
bits enables the current source. Setting or clearing both
bits at once disables the source.
C = I • dV
dT
I • t = C • V
t = (C • V)/I
C = (I • t)/V
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27.2.5 INTERRUPTS
The CTMU sets its interrupt flag (PIR3<3>) whenever
the current source is enabled, then disabled. An inter-
rupt is generated only if the corresponding interrupt
enable bit (PIE3<3>) is also set. If edge sequencing is
not enabled (i.e., Edge 1 must occur before Edge 2), it
is necessary to monitor the edge status bits and
determine which edge occurred last and caused the
interrupt.
27.3 CTMU Module Initialization
The following sequence is a general guideline used to
initialize the CTMU module:
1. Select the current source range using the
IRNGx bits (CTMUICON<1:0>).
2. Adjust the current source trim using the ITRIMx
bits (CTMUICON<7:2>).
3. Configure the edge input sources for Edge 1 and
Edge 2 by setting the EDG1SEL and EDG2SEL
bits (CTMUCONL<3:2> and <6:5>, respectively).
4. Configure the input polarities for the edge inputs
using the EDG1POL and EDG2POL bits
(CTMUCONL<4,7>).
The default configuration is for negative edge
polarity (high-to-low transitions).
5. Enable edge sequencing using the EDGSEQEN
bit (CTMUCONH<2>).
By default, edge sequencing is disabled.
6. Select the operating mode (Measurement or
Time Delay) with the TGEN bit.
The default mode is Time/Capacitance
Measurement.
7. Configure the module to automatically trigger
an A/D conversion when the second edge
event has occurred using the CTTRIG bit
(CTMUCONH<0>).
The conversion trigger is disabled by default.
8. Discharge the connected circuit by setting the
IDISSEN bit (CTMUCONH<1>).
9. After waiting a sufficient time for the circuit to
discharge, clear IDISSEN.
10. Disable the module by clearing the CTMUEN bit
(CTMUCONH<7>).
11. Clear the Edge Status bits, EDG2STAT and
EDG1STAT (CTMUCONL<1:0>).
12. Enable both edge inputs by setting the EDGEN
bit (CTMUCONH<3>).
13. Enable the module by setting the CTMUEN bit.
Depending on the type of measurement or pulse
generation being performed, one or more additional
modules may also need to be initialized and configured
with the CTMU module:
• Edge Source Generation: In addition to the
external edge input pins, CCPx Special Event
Triggers can be used as edge sources for the
CTMU.
• Capacitance or Time Measurement: The CTMU
module uses the A/D Converter to measure the
voltage across a capacitor that is connected to one
of the analog input channels.
• Pulse Generation: When generating system clock
independent, output pulses, the CTMU module
uses Comparator 2 and the associated
comparator voltage reference.
27.4 Calibrating the CTMU Module
The CTMU requires calibration for precise measure-
ments of capacitance and time, as well as for accurate
time delay. If the application only requires measurement
of a relative change in capacitance or time, calibration is
usually not necessary. An example of a less precise
application is a capacitive touch switch, in which the
touch circuit has a baseline capacitance and the added
capacitance of the human body changes the overall
capacitance of a circuit.
If actual capacitance or time measurement is required,
two hardware calibrations must take place:
• The current source needs calibration to set it to a
precise current.
• The circuit being measured needs calibration to
measure or nullify any capacitance other than that
to be measured.
27.4.1 CURRENT SOURCE CALIBRATION
The current source on board the CTMU module has a
range of ±60% nominal for each of three current
ranges. For precise measurements, it is possible to
measure and adjust this current source by placing a
high-precision resistor, RCAL, onto an unused analog
channel. An example circuit is shown in Figure 27-2.
To measure the current source:
1. Initialize the A/D Converter.
2. Initialize the CTMU.
3. Enable the current source by setting EDG1STAT
(CTMUCONL<0>).
4. Issue the settling time delay.
5. Perform the A/D conversion.
6. Calculate the current source current using
I=V/RCAL, where RCAL is a high-precision
resistance and V is measured by performing an
A/D conversion.
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The CTMU current source may be trimmed with the
trim bits in CTMUICON using an iterative process to get
the exact current desired. Alternatively, the nominal
value without adjustment may be used. That value may
be stored by software, for use in all subsequent
capacitive or time measurements.
To calculate the value for RCAL, the nominal current
must be chosen. Then, the resistance can be
calculated.
For example, if the A/D Converter reference voltage is
3.3V, use 70% of full scale (or 2.31V) as the desired
approximate voltage to be read by the A/D Converter. If
the range of the CTMU current source is selected to be
0.55 A, the resistor value needed is calculated as
RCAL = 2.31V/0.55 A, for a value of 4.2 MΩ. Similarly,
if the current source is chosen to be 5.5 A, RCAL would
be 420,000Ω, and 42,000Ω if the current source is set
to 55 A.
FIGURE 27-2: CTMU CURRENT S OURCE
CALIBRATION CIRCUIT
A value of 70% of full-scale voltage is chosen to make
sure that the A/D Converter was in a range that is well
above the noise floor. If an exact current is chosen to
incorporate the trimming bits from CTMUICON, the
resistor value of RCAL may need to be adjusted accord-
ingly. RCAL also may be adjusted to allow for available
resistor values. RCAL should be of the highest precision
available, in light of the precision needed for the circuit
that the CTMU will be measuring. A recommended
minimum would be 0.1% tolerance.
The following examples show a typical method for
performing a CTMU current calibration.
•Example 27-1 demonstrates how to initialize the
A/D Converter and the CTMU.
This routine is typical for applications using both
modules.
•Example 27-2 demonstrates one method for the
actual calibration routine.
This method manually triggers the A/D Converter to
demonstrate the entire step-wise process. It is also
possible to automatically trigger the conversion by
setting the CTMU’s CTTRIG bit (CTMUCONH<0>).
A/D Converter
CTMU
ANx
RCAL
Current Source
A/D
Trigger
MUX
A/D
PIC18F87K22
PIC18F87K22 FAMILY
DS39960C-page 392 2011 Microchip Technology Inc.
EXAMPLE 27-1: SETUP FOR CT MU CALIBRATION ROUTINES
#include "p18cxxx.h"
/**************************************************************************/
/*Setup CTMU *****************************************************************/
/**************************************************************************/
void setup(void)
{ //CTMUCON - CTMU Control register
CTMUCONH = 0x00; //make sure CTMU is disabled
CTMUCONL = 0X90;
//CTMU continues to run when emulator is stopped,CTMU continues
//to run in idle mode,Time Generation mode disabled, Edges are blocked
//No edge sequence order, Analog current source not grounded, trigger
//output disabled, Edge2 polarity = positive level, Edge2 source =
//source 0, Edge1 polarity = positive level, Edge1 source = source 0,
// Set Edge status bits to zero
//CTMUICON - CTMU Current Control Register
CTMUICON = 0x01; //0.55uA, Nominal - No Adjustment
/**************************************************************************/
//Setup AD converter;
/**************************************************************************/
TRISA=0x04; //set channel 2 as an input
// Configured AN2 as an analog channel
// ANCON0
ANCON0 = 0X04;
// ANCON1
ANCON1 = 0XE0;
// ADCON2
ADCON2bits.ADFM=1; // Resulst format 1= Right justified
ADCON2bits.ACQT=1; // Acquition time 7 = 20TAD 2 = 4TAD 1=2TAD
ADCON2bits.ADCS=2; // Clock conversion bits 6= FOSC/64 2=FOSC/32
// ADCON0
ADCON1bits.VCFG0 =0; // Vref+ = AVdd
ADCON0bits.VCFG1 =0; // Vref+ = AVdd
ADCON0bits.VCFG = 0; // Vref- = AVss
ADCON0bits.CHS=2; // Select ADC channel
ADCON0bits.ADON=1; // Turn on ADC
}
2011 Microchip Technology Inc. DS39960C-page 393
PIC18F87K22 FAMILY
EXAMPLE 27-2: CURRENT CALIBRATION ROUTINE
#include "p18cxxx.h"
#define COUNT 500 //@ 8MHz = 125uS.
#define DELAY for(i=0;i<COUNT;i++)
#define RCAL .027 //R value is 4200000 (4.2M)
//scaled so that result is in
//1/100th of uA
#define ADSCALE 1023 //for unsigned conversion 10 sig bits
#define ADREF 3.3 //Vdd connected to A/D Vr+
int main(void)
{
int i;
int j = 0; //index for loop
unsigned int Vread = 0;
double VTot = 0;
float Vavg=0, Vcal=0, CTMUISrc = 0; //float values stored for calcs
//assume CTMU and A/D have been setup correctly
//see Example 25-1 for CTMU & A/D setup
setup();
CTMUCONHbits.CTMUEN = 1; //Enable the CTMU
for(j=0;j<10;j++)
{
CTMUCONHbits.IDISSEN = 1; //drain charge on the circuit
DELAY; //wait 125us
CTMUCONHbits.IDISSEN = 0; //end drain of circuit
CTMUCONLbits.EDG1STAT = 1; //Begin charging the circuit
//using CTMU current source
DELAY; //wait for 125us
CTMUCONLbits.EDG1STAT = 0; //Stop charging circuit
PIR1bits.ADIF = 0; //make sure A/D Int not set
ADCON0bits.GO=1; //and begin A/D conv.
while(!PIR1bits.ADIF); //Wait for A/D convert complete
Vread = ADRES; //Get the value from the A/D
PIR1bits.ADIF = 0; //Clear A/D Interrupt Flag
VTot += Vread; //Add the reading to the total
}
Vavg = (float)(VTot/10.000); //Average of 10 readings
Vcal = (float)(Vavg/ADSCALE*ADREF);
CTMUISrc = Vcal/RCAL; //CTMUISrc is in 1/100ths of uA
}
PIC18F87K22 FAMILY
DS39960C-page 394 2011 Microchip Technology Inc.
27.4.2 CAPACITANCE CALIBRATION
There is a small amount of capacitance from the inter-
nal A/D Converter sample capacitor as well as stray
capacitance from the circuit board traces and pads that
affect the precision of capacitance measurements. A
measurement of the stray capacitance can be taken by
making sure the desired capacitance to be measured
has been removed.
After removing the capacitance to be measured:
1. Initialize the A/D Converter and the CTMU.
2. Set EDG1STAT (= 1).
3. Wait for a fixed delay of time, t.
4. Clear EDG1STAT.
5. Perform an A/D conversion.
6. Calculate the stray and A/D sample capacitances:
Where:
•I is known from the current source measurement
step
•t is a fixed delay
•V is measured by performing an A/D conversion
This measured value is then stored and used for
calculations of time measurement or subtracted for
capacitance measurement. For calibration, it is
expected that the capacitance of CSTRAY +CAD is
approximately known; CAD is approximately 4 pF.
An iterative process may be required to adjust the time,
t, that the circuit is charged to obtain a reasonable volt-
age reading from the A/D Converter. The value of t may
be determined by setting COFFSET to a theoretical value
and solving for t. For example, if CSTRAY is theoretically
calculated to be 11 pF, and V is expected to be 70% of
VDD or 2.31V, t would be:
or 63 s.
See Example 27-3 for a typical routine for CTMU
capacitance calibration.
COFFSET = CSTRAY + CAD = (I • t)/V
(4 pF + 11 pF) • 2.31V/0.55 A
2011 Microchip Technology Inc. DS39960C-page 395
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EXAMPLE 27-3: CAPACITANCE CALIBRATION ROUTINE
#include "p18cxxx.h"
#define COUNT 25 //@ 8MHz INTFRC = 62.5 us.
#define ETIME COUNT*2.5 //time in uS
#define DELAY for(i=0;i<COUNT;i++)
#define ADSCALE 1023 //for unsigned conversion 10 sig bits
#define ADREF 3.3 //Vdd connected to A/D Vr+
#define RCAL .027 //R value is 4200000 (4.2M)
//scaled so that result is in
//1/100th of uA
int main(void)
{
int i;
int j = 0; //index for loop
unsigned int Vread = 0;
float CTMUISrc, CTMUCap, Vavg, VTot, Vcal;
//assume CTMU and A/D have been setup correctly
//see Example 25-1 for CTMU & A/D setup
setup();
CTMUCONHbits.CTMUEN = 1; //Enable the CTMU
for(j=0;j<10;j++)
{
CTMUCONHbits.IDISSEN = 1; //drain charge on the circuit
DELAY; //wait 125us
CTMUCONHbits.IDISSEN = 0; //end drain of circuit
CTMUCONLbits.EDG1STAT = 1; //Begin charging the circuit
//using CTMU current source
DELAY; //wait for 125us
CTMUCONLbits.EDG1STAT = 0; //Stop charging circuit
PIR1bits.ADIF = 0; //make sure A/D Int not set
ADCON0bits.GO=1; //and begin A/D conv.
while(!PIR1bits.ADIF); //Wait for A/D convert complete
Vread = ADRES; //Get the value from the A/D
PIR1bits.ADIF = 0; //Clear A/D Interrupt Flag
VTot += Vread; //Add the reading to the total
}
Vavg = (float)(VTot/10.000); //Average of 10 readings
Vcal = (float)(Vavg/ADSCALE*ADREF);
CTMUISrc = Vcal/RCAL; //CTMUISrc is in 1/100ths of uA
CTMUCap = (CTMUISrc*ETIME/Vcal)/100;
}
PIC18F87K22 FAMILY
DS39960C-page 396 2011 Microchip Technology Inc.
27.5 Measuring Capacit ance with the
CTMU
There are two ways to measure capacitance with the
CTMU. The absolute method measures the actual
capacitance value. The relative method only measures
for any change in the capacitance.
27.5.1 ABSOLUTE CAPACITANCE
MEASUREMENT
For absolute capacitance measurements, both the
current and capacitance calibration steps found in
Section 27 .4 “Calibratin g the CTMU M odule” should
be followed.
To perform these measurements:
1. Initialize the A/D Converter.
2. Initialize the CTMU.
3. Set EDG1STAT.
4. Wait for a fixed delay, T.
5. Clear EDG1STAT.
6. Perform an A/D conversion.
7. Calculate the total capacitance, CTOTAL = (I * T)/V,
where:
•I is known from the current source
measurement step (Section 27 .4.1 “Current
Source Calibration”)
•T is a fixed delay
•V is measured by performing an A/D conversion
8. Subtract the stray and A/D capacitance
(COFFSET from Section 27.4.2 “Capacitance
Calibration”) from CTOTAL to determine the
measured capacitance.
27.5.2 RELATIVE CHARGE
MEASUREMENT
Not all applications require precise capacitance
measurements. When detecting a valid press of a
capacitance-based switch, only a relative change of
capacitance needs to be detected.
In such an application, when the switch is open (or not
touched), the total capacitance is the capacitance of the
combination of the board traces, the A/D Converter and
other elements. A larger voltage will be measured by the
A/D Converter. When the switch is closed (or touched),
the total capacitance is larger due to the addition of the
capacitance of the human body to the above listed
capacitances and a smaller voltage will be measured by
the A/D Converter.
To detect capacitance changes simply:
1. Initialize the A/D Converter and the CTMU.
2. Set EDG1STAT.
3. Wait for a fixed delay.
4. Clear EDG1STAT.
5. Perform an A/D conversion.
The voltage measured by performing the A/D conver-
sion is an indication of the relative capacitance. In this
case, no calibration of the current source or circuit
capacitance measurement is needed. (For a sample
software routine for a capacitive touch switch, see
Example 27-4.)
2011 Microchip Technology Inc. DS39960C-page 397
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EXAMPLE 27-4: ROUTINE FOR CAPACITIVE TOUCH SWITCH
#include "p18cxxx.h"
#define COUNT 500 //@ 8MHz = 125uS.
#define DELAY for(i=0;i<COUNT;i++)
#define OPENSW 1000 //Un-pressed switch value
#define TRIP 300 //Difference between pressed
//and un-pressed switch
#define HYST 65 //amount to change
//from pressed to un-pressed
#define PRESSED 1
#define UNPRESSED 0
int main(void)
{
unsigned int Vread; //storage for reading
unsigned int switchState;
int i;
//assume CTMU and A/D have been setup correctly
//see Example 25-1 for CTMU & A/D setup
setup();
CTMUCONHbits.CTMUEN = 1; //Enable the CTMU
CTMUCONHbits.IDISSEN = 1; //drain charge on the circuit
DELAY; //wait 125us
CTMUCONHbits.IDISSEN = 0; //end drain of circuit
CTMUCONLbits.EDG1STAT = 1; //Begin charging the circuit
//using CTMU current source
DELAY; //wait for 125us
CTMUCONLbits.EDG1STAT = 0; //Stop charging circuit
PIR1bits.ADIF = 0; //make sure A/D Int not set
ADCON0bits.GO=1; //and begin A/D conv.
while(!PIR1bits.ADIF); //Wait for A/D convert complete
Vread = ADRES; //Get the value from the A/D
if(Vread < OPENSW - TRIP)
{
switchState = PRESSED;
}
else if(Vread > OPENSW - TRIP + HYST)
{
switchState = UNPRESSED;
}
}
PIC18F87K22 FAMILY
DS39960C-page 398 2011 Microchip Technology Inc.
27.6 Measuring Time with the CTMU
Module
Time can be precisely measured after the ratio (C/I) is
measured from the current and capacitance calibration
step. To do that:
1. Initialize the A/D Converter and the CTMU.
2. Set EDG1STAT.
3. Set EDG2STAT.
4. Perform an A/D conversion.
5. Calculate the time between edges as T = (C/I) * V,
where:
•I is calculated in the current calibration
step (Section 2 7.4. 1 “Curr ent Sour ce
Calibration”)
•C is calculated in the capacitance calibra-
tion step (S ecti on 2 7.4.2 “C apacitance
Calibration”)
•V is measured by performing the A/D conversion
It is assumed that the time measured is small enough
that the capacitance, COFFSET, provides a valid voltage
to the A/D Converter. For the smallest time measure-
ment, always set the A/D Channel Select register
(AD1CHS) to an unused A/D channel, the correspond-
ing pin for which is not connected to any circuit board
trace. This minimizes added stray capacitance, keep-
ing the total circuit capacitance close to that of the A/D
Converter itself (25 pF).
To measure longer time intervals, an external capacitor
may be connected to an A/D channel and that channel
selected whenever making a time measurement.
FIGURE 27-3: TYPICAL CONNECTIONS AND INTERNAL CONFIGURATION FOR TIME
MEASUREMENT
A/D Converter
CTMU
CTED1
CTED2
ANX
Output
Pulse
EDG1
EDG2
CAD
RPR
Current Source
PIC18F87K22
2011 Microchip Technology Inc. DS39960C-page 399
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27.7 Creating a Delay with the CTMU
Module
A unique feature on board the CTMU module is its ability
to generate system clock independent output pulses
based on either an external voltage or an external
capacitor value. When using an external voltage, this is
accomplished using the CTDIN input pin as a trigger for
the pulse delay. When using an external capacitor
value, this is accomplished using the internal compara-
tor voltage reference module and Comparator 2 input
pin.The pulse is output onto the CTPLS pin. To enable
this mode, set the TGEN bit.
See Figure 27-4 for an example circuit. When
CTMUDS (ODCON3<0>) is cleared, the pulse delay is
determined by the output of Comparator 2, and when it
is set, the pulse delay is determined by the input of
CTDIN. CDELAY is chosen by the user to determine the
output pulse width on CTPLS. The pulse width is calcu-
lated by T = (CDELAY/I)*V, where I is known from the
current source measurement step (Section 27.4.1
“Current Source Calibration”) and V is the internal
reference voltage (CVREF).
An example use of the external capacitor feature is
interfacing with variable capacitive-based sensors,
such as a humidity sensor. As the humidity varies, the
pulse-width output on CTPLS will vary. An example use
of the CTDIN feature is interfacing with a digital sensor.
The CTPLS output pin can be connected to an input
capture pin and the varying pulse width measured to
determine the sensor’s output in the application.
To use this feature:
1. If CTMUDS is cleared, initialize Comparator 2.
2. If CTMUDS is cleared, initialize the comparator
voltage reference.
3. Initialize the CTMU and enable time delay
generation by setting the TGEN bit.
4. Set EDG1STAT.
When CTMUDS is cleared, as soon as CDELAY charges
to the value of the voltage reference trip point, an out-
put pulse is generated on CTPLS. When CTMUDS is
set, as soon as CTDIN is set, an output pulse is
generated on CTPLS.
FIGURE 27-4: TYPICAL CONNECTIONS AND INTERNAL CONFIGURATION FOR PULSE
DELAY GENERATION
C2
CVREF
CTPLS
Current Source
Comparator
CTMU
CTED1
CTMUI
CDELAY
EDG1
PIC18F87K22
CTMUDS
C1
External Reference
External Comparator
CTDIN
PIC18F87K22 FAMILY
DS39960C-page 400 2011 Microchip Technology Inc.
27.8 Measuring Temperature with the
CTMU Module
The CTMU, along with an internal diode, can be used
to measure the temperature. The ADC can be con-
nected to the internal diode and the CTMU module can
source the current to the diode. The ADC reading will
reflect the temperature. With the increase, the ADC
readings will go low. This can be used for low-cost
temperature measurement applications.
EXAMPLE 27-5: ROUTINE FOR TEMPERATURE MEASUREMENT USING INTERNAL DIODE
// Initialize CTMU
CTMUICON = 0x03;
CTMUCONHbits.CTMUEN = 1;
CTMUCONLbits.EDG1STAT = 1;
// Initialize ADC
ADCON0 = 0xE5; // Enab le ADC and connect to Internal diode
ADCON1 = 0x00;
ADCON2 = 0xBE; //Right Justified
ADCON0bits.GO = 1; // Start conversion
while(ADCON0bits.G0);
Temp = ADRES; // Read ADC results (inversely proportional to temperature)
Note: The temperature diode is not calibrated or standardized; the user must calibrate the diode to their application.
2011 Microchip Technology Inc. DS39960C-page 401
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27.9 Operation During Sleep/Idle Modes
27.9.1 SLEEP MODE
When the device enters any Sleep mode, the CTMU
module current source is always disabled. If the CTMU
is performing an operation that depends on the current
source when Sleep mode is invoked, the operation may
not terminate correctly. Capacitance and time
measurements may return erroneous values.
27.9.2 IDLE MODE
The behavior of the CTMU in Idle mode is determined
by the CTMUSIDL bit (CTMUCONH<5>). If CTMUSIDL
is cleared, the module will continue to operate in Idle
mode. If CTMUSIDL is set, the module’s current source
is disabled when the device enters Idle mode. In this
case, if the module is performing an operation when
Idle mode is invoked, the results will be similar to those
with Sleep mode.
27.10 Effects of a Reset on CTMU
Upon Reset, all registers of the CTMU are cleared. This
disables the CTMU module, turns off its current source
and returns all configuration options to their default set-
tings. The module needs to be re-initialized following
any Reset.
If the CTMU is in the process of taking a measurement
at the time of Reset, the measurement will be lost. A
partial charge may exist on the circuit that was being
measured, which should be properly discharged before
the CTMU makes subsequent attempts to make a
measurement. The circuit is discharged by setting and
clearing the IDISSEN bit (CTMUCONH<1>) while the
A/D Converter is connected to the appropriate channel.
TABLE 27-1: REGISTERS ASSOCIATED WITH CTMU MODULE
Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
CTMUCONH CTMUEN — CTMUSIDL TGEN EDGEN EDGSEQEN IDISSEN CTTRIG
CTMUCONL EDG2POL EDG2SEL1 EDG2SEL0 EDG1POL EDG1SEL1 EDG1SEL0 EDG2STAT EDG1STAT
CTMUICON ITRIM5 ITRIM4 ITRIM3 ITRIM2 ITRIM1 ITRIM0 IRNG1 IRNG0
PIR3 TMR5GIF —RC2IF TX2IF CTMUIF CCP2IF CCP1IF RTCCIF
PIE3 TMR5GIE —RC2IE TX2IE CTMUIE CCP2IE CCP1IE RTCCIE
IPR3 TMR5GIP —RC2IP TX2IP CTMUIP CCP2IP CCP1IP RTCCIP
Legend: — = unimplemented, read as ‘0’. Shaded cells are not used during ECCP operation.
PIC18F87K22 FAMILY
DS39960C-page 402 2011 Microchip Technology Inc.
NOTES:
2011 Microchip Technology Inc. DS39960C-page 403
PIC18F87K22 FAMILY
28.0 SPECIAL FEATURES OF THE
CPU
The PIC18F87K22 family of devices includes several
features intended to maximize reliability and minimize
cost through elimination of external components.
These include:
• Oscillator Selection
• Resets:
- Power-on Reset (POR)
- Power-up Timer (PWRT)
- Oscillator Start-up Timer (OST)
- Brown-out Reset (BOR)
• Interrupts
• Watchdog Timer (WDT) and On-chip Regulator
• Fail-Safe Clock Monitor
• Two-Speed Start-up
• Code Protection
• ID Locations
• In-Circuit Serial Programming™
The oscillator can be configured for the application
depending on frequency, power, accuracy and cost. All
of the options are discussed in detail in Section 3.0
“Oscillator Configurations”.
A complete discussion of device Resets and interrupts
is available in previous sections of this data sheet.
In addition to their Power-up and Oscillator Start-up
Timers provided for Resets, the PIC18F87K22 family of
devices has a Watchdog Timer, which is either perma-
nently enabled via the Configuration bits or software
controlled (if configured as disabled).
The inclusion of an internal RC oscillator (LF-INTOSC)
also provides the additional benefits of a Fail-Safe
Clock Monitor (FSCM) and Two-Speed Start-up. FSCM
provides for background monitoring of the peripheral
clock and automatic switchover in the event of its fail-
ure. Two-Speed Start-up enables code to be executed
almost immediately on start-up, while the primary clock
source completes its start-up delays.
All of these features are enabled and configured by
setting the appropriate Configuration register bits.
28.1 Configuration Bits
The Configuration bits can be programmed (read as
‘0’) or left unprogrammed (read as ‘1’) to select various
device configurations. These bits are mapped starting
at program memory location, 300000h.
The user will note that address, 300000h, is beyond the
user program memory space. In fact, it belongs to the
configuration memory space (300000h-3FFFFFh),
which can only be accessed using table reads and
table writes.
Software programming the Configuration registers is
done in a manner similar to programming the Flash
memory. The WR bit in the EECON1 register starts a
self-timed write to the Configuration register. In normal
operation mode, a TBLWT instruction with the TBLPTR
pointing to the Configuration register sets up the address
and the data for the Configuration register write. Setting
the WR bit starts a long write to the Configuration regis-
ter. The Configuration registers are written a byte at a
time. To write or erase a configuration cell, a TBLWT
instruction can write a ‘1’ or a ‘0’ into the cell. For
additional details on Flash programming, refer to
Section 7.5 “Writing to Flash Program Memory”.
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DS39960C-page 404 2011 Microchip Technology Inc.
TABLE 28-1: CONFIGURATION BITS AND DEVICE IDs
File Nam e Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Default/
Unprogrammed
Value
300000h CONFIG1L —XINST — SOSCSEL1 SOSCSEL0 INTOSCSEL —RETEN
-1-1 1--1
300001h CONFIG1H IESO FCMEN — PLLCFG FOSC3 FOSC2 FOSC1 FOSC0
00-0 100 0
300002h CONFIG2L — BORPWR1 BORWPR0 BORV1 BORV0 BOREN1 BOREN0 PWRTEN
-111 111 1
300003h CONFIG2H — WDTPS4 WDTPS3 WDTPS2 WDTPS1 WDTPS0 WDTEN1 WDTEN0
-111 111 1
300004h CONFIG3L WAIT
(2)
BW
(2)
ABW1
(2)
ABW0
(2)
EASHFT
(2)
— —RTCOSC
---- --- 1
300005h CONFIG3H MCLRE — — — MSSPMSK —ECCPMX
(2)
CCP2MX
1--- 1-1 1
300006h CONFIG4L DEBUG ——BBSIZ0— — —STVREN
1--1 --- 1
300008h CONFIG5L CP7
(1)
CP6
(1)
CP5
(1)
CP4
(1)
CP3 CP2 CP1 CP0
1111 111 1
300009h CONFIG5H CPD CPB — — — — — —
11-- --- -
30000Ah CONFIG6L WRT7
(1)
WRT6
(1)
WRT5
(1)
WRT4
(1)
WRT3 WRT2 WRT1 WRT0
1111 111 1
30000Bh CONFIG6H WRTD WRTB WRTC — — — — —
111- --- -
30000Ch CONFIG7L EBTR7
(1)
EBTR6
(1)
EBTR5
(1)
EBTR4
(1)
EBTR3 EBTR2 EBTR1 EBTR0
1111 111 1
30000Dh CONFIG7H —EBTRB — — — — — —
-1-- --- -
3FFFFEh DEVID1
(3)
DEV2 DEV1 DEV0 REV4 REV3 REV2 REV1 REV0
xxxx xxx x
3FFFFFh DEVID2
(3)
DEV10 DEV9 DEV8 DEV7 DEV6 DEV5 DEV4 DEV3
xxxx xxx x
Legend:
x
= unknown,
u
= unchanged,
-
= unimplemented,
q
= value depends on condition. Shaded cells are unimplemented, read as ‘
0
’.
Note 1:
Implemented only on the PIC18F67K22 and PIC18F87K22 devices.
2:
Implemented only on the 80-pin devices (PIC18F8XK22).
3:
See Register 28-14 for DEVID1 values. DEVID registers are read-only and cannot be programmed by the user.
2011 Microchip Technology Inc. DS39960C-page 405
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REGISTER 28-1: CONFIG1L: CONFIGURATION REGISTER 1 LOW (BYTE ADDRESS 300000h)
U-0 R/P-1 U-0 R/P-1 R/P-1 R/P-1 U-0 R/P-1
—XINST— SOSCSEL1 SOSCSEL0 INTOSCSEL — RETEN
bit 7 bit 0
Legend: P = Programmable bit
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 Unimplemented: Read as ‘0’
bit 6 XINST: Extended Instruction Set Enable bit
1 = Instruction set extension and Indexed Addressing mode are enabled
0 = Instruction set extension and Indexed Addressing mode are disabled (Legacy mode)
bit 5 Unimplemented: Read as ‘0’
bit 4-3 SOSCSEL<1:0>: SOSC Power Selection and Mode Configuration bits
11 = High-power SOSC circuit is selected
10 = Digital (SCLKI) mode; I/O port functionality of RC0 and RC1 is enabled
01 = Low-power SOSC circuit is selected
00 = Reserved
bit 2 INTOSCSEL: LF-INTOSC Low-power Enable bit
1 = LF-INTOSC is in High-Power mode during Sleep
0 = LF-INTOSC is in Low-Power mode during Sleep
bit 1 Unimplemented: Read as ‘0’
bit 0 RETEN: VREG Sleep Enable bit
1 = Regulator power while in Sleep mode is controlled by VREGSLP (WDTCON<7>)
0 = Regulator power while in Sleep mode is controlled by SRETEN (WDTCON<4>). Ultra low-power
regulator is enabled.
PIC18F87K22 FAMILY
DS39960C-page 406 2011 Microchip Technology Inc.
REGISTER 28-2: CONFIG1H: CONFIGURATION REGIST ER 1 HIGH (BYTE ADDRESS 300001h)
R/P-0 R/P-0 U-0 U-0 R/P-1 R/P-0 R/P-0 R/P-0
IESO FCMEN —PLLCFG
(1) FOSC3(2) FOSC2(2) FOSC1(2) FOSC0(2)
bit 7 bit 0
Legend: P = Programmable bit
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 IESO: Internal/External Oscillator Switchover bit
1 = Two-Speed Start-up is enabled
0 = Two-Speed Start-up is disabled
bit 6 FCMEN: Fail-Safe Clock Monitor Enable bit
1 = Fail-Safe Clock Monitor is enabled
0 = Fail-Safe Clock Monitor is disabled
bit 5 Unimplemented: Read as ‘0’
bit 4 PLLCFG: 4x PLL Enable bit(1)
1 = Oscillator is multiplied by 4
0 = Oscillator is used directly
bit 3-0 FOSC<3:0>: Oscillator Selection bits(2)
1101 = EC1, EC oscillator (low power, DC-160 kHz)
1100 = EC1IO, EC oscillator with CLKOUT function on RA6 (low power, DC-160 kHz)
1011 = EC2, EC oscillator (med ium p ower, 1 60 kHz-16 MHz)
1010 = EC2IO, EC oscillator with CLKOUT function on RA6 (medium pow er, DC-160 kHz- 16 MH z )
1001 = INTIO1, internal RC oscillator with CLKOUT function on RA6
1000 = INTIO2, internal RC oscillator
0111 = RC, external RC oscillator
0110 = RCIO, external RC oscillator with CKLOUT function on RA6
0101 = EC3, EC oscillator (high power, 4 MHz-64 MHz)
0100 = EC3IO, EC oscillator with CLKOUT function on RA6 (high power, 4 MHz-6 4 MHz)
0011 = HS1, HS oscillator (medium power, 4 MHz-16 MHz)
0010 = HS2, HS oscillator (high power, 16 MHz-25 MHz)
0001 = XT oscillator
0000 = LP oscillator
Note 1: Not valid for the INTIOx PLL mode.
2: INTIO + PLL can be enabled only by the PLLEN bit (OSCTUNE<6>). Other PLL modes can be enabled by
either the PLLEN bit or the PLLCFG (CONFIG1H<4>) bit.
2011 Microchip Technology Inc. DS39960C-page 407
PIC18F87K22 FAMILY
REGISTER 28-3: CONFIG2L: CONFIGURATION REGISTER 2 LOW (BYTE ADDRESS 300002h)
U-0 R/P-1 R/P-1 R/P-1 R/P-1 R/P-1 R/P-1 R/P-1
—BORPWR1
(1) BORPWR0(1) BORV1(1) BORV0(1) BOREN1(2) BOREN0(2) PWRTEN(2)
bit 7 bit 0
Legend: P = Programmable bit
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 Unimplemented: Read as ‘0’
bit 6-5 BORPWR<1:0>: BORMV Power-Level bits(1)
11 = ZPBORVMV instead of BORMV is selected
10 = BORMV is set to a high-power level
01 = BORMV is set to a medium power level
00 = BORMV is set to a low-power level
bit 4-3 BORV<1:0>: Brown-out Reset Voltage bits(1)
11 =VBORMV is set to 1.8V
10 =VBORMV is set to 2.0V
01 =VBORMV is set to 2.7V
00 =VBORMV is set to 3.0V
bit 2-1 BOREN<1:0>: Brown-out Reset Enable bits(2)
11 = Brown-out Reset is enabled in hardware only (SBOREN is disabled)
10 = Brown-out Reset is enabled in hardware only and disabled in Sleep mode (SBOREN is disabled)
01 = Brown-out Reset is enabled and controlled by software (SBOREN is enabled)
00 = Brown-out Reset is disabled in hardware and software
bit 0 PWRTEN: Power-up Timer Enable bit(2)
1 = PWRT is disabled
0 = PWRT is enabled
Note 1: For the specifications, see Section 31.1 “DC Characteristics: Supply Voltage PIC18F87K22 Family
(Industrial)”.
2: The Power-up Timer is decoupled from Brown-out Reset, allowing these features to be independently
controlled.
PIC18F87K22 FAMILY
DS39960C-page 408 2011 Microchip Technology Inc.
REGISTER 28-4: CONFIG2H: CONFIGURATION REGIST ER 2 HIGH (BYTE ADDRESS 300003h)
U-0 R/P-1 R/P-1 R/P-1 R/P-1 R/P-1 R/P-1 R/P-1
— WDTPS4 WDTPS3 WDTPS2 WDTPS1 WDTPS0 WDTEN1 WDTEN0
bit 7 bit 0
Legend: P = Programmable bit
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 Unimplemented: Read as ‘0’
bit 6-2 WDTPS<4:0>: Watchdog Timer Postscale Select bits
10101-11111 = Reserved
10100 = 1:1,048,576 (4,194.304s)
10011 = 1:524,288 (2,097.152s)
10010 = 1:262,144 (1,048.576s)
10001 = 1:131,072 (524.288s)
10000 = 1:65,536 (262.144s)
01111 = 1:32,768 (131.072s)
01110 = 1:16,384 (65.536s)
01101 = 1:8,192 (32.768s)
01100 = 1:4,096 (16.384s)
01011 = 1:2,048 (8.192s)
01010 = 1:1,024 (4.096s)
01001 = 1:512 (2.048s)
01000 = 1:256 (1.024s)
00111 = 1:128 (512 ms)
00110 = 1:64 (256 ms)
00101 = 1:32 (128 ms)
00100 = 1:16 (64 ms)
00011 = 1:8 (32 ms)
00010 = 1:4 (16 ms)
00001 = 1:2 (8 ms)
00000 = 1:1 (4 ms)
bit 1-0 WDTEN<1:0>: Watchdog Timer Enable bits
11 = WDT is enabled in hardware; SWDTEN bit is disabled
10 = WDT is controlled by the SWDTEN bit setting
01 = WDT is enabled only while the device is active and disabled in Sleep mode; SWDTEN bit is
disabled
00 = WDT is disabled in hardware; SWDTEN bit is disabled
2011 Microchip Technology Inc. DS39960C-page 409
PIC18F87K22 FAMILY
REGISTER 28-5: CONFIG3L: CONFIGURATION REGISTER 3 LOW (BYTE ADDRESS 300004h)
U-1 U-1 U-1 U-1 U-1 U-0 U-0 R/P-1
WAIT(1) BW(1) ABW1(1) ABW0(1) EASHFT(1) — —RTCOSC
bit 7 bit 0
Legend: P = Programmable bit
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 WAIT: External Bus Wait Enable bit(1)
1 = Wait states on the external bus are disabled
0 = Wait states on the external bus are enabled and selected by MEMCON <5:4>
bit 6 BW: Data Bus Width Select bit(1)
1 = 16-Bit Data Width modes
0 = 8-Bit Data Width modes
bit 5-4 ABW: External Memory Bus Configuration bits(1)
11 = 8-Bit Address mode (Microcontroller mode)
10 = 12-Bit Address mode
01 = 16-Bit Address mode
00 = 20-Bit Address mode
bit 3 EASHFT: External Address Bus Shift Enable bit(1)
1 = Address shifting is enabled; external address is shifted to start at 000000h
0 = Address shifting is disabled; external address bus reflects the PC value
bit 2-1 Unimplemented: Read as ‘0’
bit 0 RTCOSC: RTCC Reference Clock Select bit
1 = RTCC uses SOSC as the reference clock
0 = RTCC uses LF-INTOSC as the reference clock
Note 1: Unimplemented on 64-pin devices (PIC18F6XK22), read as ‘0’.
PIC18F87K22 FAMILY
DS39960C-page 410 2011 Microchip Technology Inc.
REGISTER 28-6: CONFIG3H: CONFIGURATION REGIST ER 3 HIGH (BYTE ADDRESS 300005h)
R/P-1 U-0 U-0 U-0 R/P-1 U-0 R/P-1 R/P-1
MCLRE — — — MSSPMSK —ECCPMX
(1) CCP2MX
bit 7 bit 0
Legend: P = Programmable bit
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 MCLRE: MCLR Pin Enable bit
1 = MCLR pin is enabled; RG5 input pin is disabled
0 = RG5 input pin is enabled; MCLR is disabled
bit 6-4 Unimplemented: Read as ‘0’
bit 3 MSSPMSK: MSSP V3 7-Bit Address Masking Mode Enable bit
1 = 7-Bit Address Masking mode is enabled
0 = 5-Bit Address Masking mode is enabled
bit 2 Unimplemented: Read as ‘0’
bit 1 ECCPMX: ECCP MUX bit(1)
1 =
- ECCP1 (P1B/P1C) is multiplexed onto RE6 and RE5, CCP6 onto RE6, and CCP7 onto RE5
- ECCP3 (P3B/P3C) is multiplexed onto RE4 and RE3, CCP8 onto RE4, and CCP9 onto RE3
0 =
- ECCP1 (P1B/P1C) is multiplexed onto RH7 and RH6, CCP6 onto RH7, and CCP7(2) onto RH6
- ECCP3 (P3B/P3C) is multiplexed onto RH5 and RH4, CCP8 onto RH5, and CCP9(2) onto RH4
bit 0 CCP2MX: ECCP2 MUX bit
1 = ECCP2 is multiplexed with RC1
0 = ECCP2 is multiplexed with RB3 in Extended Microcontroller mode; ECCP2 is multiplexed with
RE7 in Microcontroller mode
Note 1: Unimplemented on 64-pin devices (PIC18F6XK22), read as ‘0’.
2: Not implemented on 32K devices (PIC18F65K22 and PIC18F85K22).
2011 Microchip Technology Inc. DS39960C-page 411
PIC18F87K22 FAMILY
REGISTER 28-7: CONFIG4L: CONFIGURATION REGISTER 4 LOW (BYTE ADDRESS 300006h)
R/P-1 U-0 U-0 R/P-0 U-0 U-0 U-0 R/P-1
DEBUG —— BBSIZ0 — — —STVREN
bit 7 bit 0
Legend: P = Programmable bit
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 DEBUG: Background Debugger Enable bit
1 = Background debugger is disabled, RB6 and RB7 are configured as general purpose I/O pins
0 = Background debugger is enabled, RB6 and RB7 are dedicated to In-Circuit Debug
bit 6-5 Unimplemented: Read as ‘0’
bit 4 BBSIZ0: Boot Block Size Select bit
1 = 2 kW boot block size
0 = 1 kW boot block size
bit 3-1 Unimplemented: Read as ‘0’
bit 0 STVREN: Stack Full/Underflow Reset Enable bit
1 = Stack full/underflow will cause Reset
0 = Stack full/underflow will not cause Reset
PIC18F87K22 FAMILY
DS39960C-page 412 2011 Microchip Technology Inc.
REGISTER 28-8: CONFIG5L: CONFIGURATION REGISTER 5 LOW (BYTE ADDRESS 300008h)
R/C-1 R/C-1 R/C-1 R/C-1 R/C-1 R/C-1 R/C-1 R/C-1
CP7(1) CP6(1) CP5(1) CP4(1) CP3 CP2 CP1 CP0
bit 7 bit 0
Legend: C = Clearable bit
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 CP7: Code Protection bit(1)
1 = Block 7, not code-protected(2)
0 = Block 7, code-protected(2)
bit 6 CP6: Code Protection bit(1)
1 = Block 6, not code-protected(2)
0 = Block 6, code-protected(2)
bit 5 CP5: Code Protection bit(1)
1 = Block 5, not code-protected(2)
0 = Block 5, code-protected(2)
bit 4 CP4: Code Protection bit(1)
1 = Block 4, not code-protected(2)
0 = Block 4, code-protected(2)
bit 3 CP3: Code Protection bit
1 = Block 3, not code-protected(2)
0 = Block 3, code-protected(2)
bit 2 CP2: Code Protection bit
1 = Block 2, not code-protected(2)
0 = Block 2, code-protected(2)
bit 1 CP1: Code Protection bit
1 = Block 1, not code-protected(2)
0 = Block 1, code-protected(2)
bit 0 CP0: Code Protection bit
1 = Block 0, not code-protected(2)
0 = Block 0, code-protected(2)
Note 1: This bit is available only on PIC18F67K22 and PIC18F87K22 devices.
2: For the memory size of the blocks, see Figure 28-6.
2011 Microchip Technology Inc. DS39960C-page 413
PIC18F87K22 FAMILY
REGISTER 28-9: CONFIG5H: CONFIGURATION REGIST ER 5 HIGH (BYTE ADDRESS 300009h)
R/C-1 R/C-1 U-0 U-0 U-0 U-0 U-0 U-0
CPD CPB — — — — — —
bit 7 bit 0
Legend: C = Clearable bit
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 CPD: Data EEPROM Code Protection bit
1 = Data EEPROM is not code-protected
0 = Data EEPROM is code-protected
bit 6 CPB: Boot Block Code Protection bit
1 = Boot block, not code-protected(1)
0 = Boot block, code-protected(1)
bit 5-0 Unimplemented: Read as ‘0’
Note 1: For the memory size of the blocks, see Figure 28-6. The boot block size changes with BBSIZ0.
PIC18F87K22 FAMILY
DS39960C-page 414 2011 Microchip Technology Inc.
REGISTER 28-10: CONFIG6L: CONFIGURATION REGISTER 6 LOW (BYTE ADDRESS 30000Ah)
R/C-1 R/C-1 R/C-1 R/C-1 R/C-1 R/C-1 R/C-1 R/C-1
WRT7(1) WRT6(1) WRT5(1) WRT4(1) WRT3 WRT2 WRT1 WRT0
bit 7 bit 0
Legend: C = Clearable bit
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 WRT7: Write Protection bit(1)
1 = Block 7, not write-protected(2)
0 = Block 7, write-protected(2)
bit 6 WRT6: Write Protection bit(1)
1 = Block 6, not write-protected(2)
0 = Block 6, write-protected(2)
bit 5 WRT5: Write Protection bit(1)
1 = Block 5, not write-protected(2)
0 = Block 5, write-protected(2)
bit 4 WRT4: Write Protection bit(1)
1 = Block 4, not write-protected(2)
0 = Block 4, write-protected(2)
bit 3 WRT3: Write Protection bit
1 = Block 3, not write-protected(2)
0 = Block 3, write-protected(2)
bit 2 WRT2: Write Protection bit
1 = Block 2, not write-protected(2)
0 = Block 2, write-protected(2)
bit 1 WRT1: Write Protection bit
1 = Block 1, not write-protected(2)
0 = Block 1, write-protected(2)
bit 0 WRT0: Write Protection bit
1 = Block 0, not write-protected(2)
0 = Block 0, write-protected(2)
Note 1: This bit is available only on PIC18F67K22 and PIC18F87K22.
2: For the memory size of the blocks, see Figure 28-6.
2011 Microchip Technology Inc. DS39960C-page 415
PIC18F87K22 FAMILY
REGISTER 28-11: CONFIG6H: CONFIGURATION REGIS TER 6 HIGH (BYTE ADDRESS 30000Bh)
R/C-1 R/C-1 R-1 U-0 U-0 U-0 U-0 U-0
WRTD WRTB WRTC(1) — — — — —
bit 7 bit 0
Legend: C = Clearable bit
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 WRTD: Data EEPROM Write Protection bit
1 = Data EEPROM not write-protected
0 = Data EEPROM write-protected
bit 6 WRTB: Boot Block Write Protection bit
1 = Boot block, not write-protected(2)
0 = Boot block, write-protected(2)
bit 5 WRTC: Configuration Register Write Protection bit(1)
1 = Configuration registers, not write-protected(2)
0 = Configuration registers, write-protected(2)
bit 4-0 Unimplemented: Read as ‘0’
Note 1: This bit is read-only in normal execution mode; it can be written only in Program mode.
2: For the memory size of the blocks, see Figure 28-6.
PIC18F87K22 FAMILY
DS39960C-page 416 2011 Microchip Technology Inc.
REGISTER 28-12: CONFIG7L: CONFIGURATION REGISTER 7 LOW (BYTE ADDRESS 30000Ch)
R/C-1 R/C-1 R/C-1 R/C-1 R/C-1 R/C-1 R/C-1 R/C-1
EBTR7(1,3) EBTR6(1,3) EBTR5(1,3) EBTR4(1,3) EBTR3(3) EBTR2(3) EBTR1(3) EBTR0(3)
bit 7 bit 0
Legend: C = Clearable bit
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 EBTR7: Table Read Protection bit(1,3)
1 = Block 7, not protected from table reads executed in other blocks(2)
0 = Block 7, protected from table reads executed in other blocks(2)
bit 6 EBTR6: Table Read Protection bit(1,3)
1 = Block 6, not protected from table reads executed in other blocks(2)
0 = Block 6, protected from table reads executed in other blocks(2)
bit 5 EBTR5: Table Read Protection bit(1,3)
1 = Block 5, not protected from table reads executed in other blocks(2)
0 = Block 5, protected from table reads executed in other blocks(2)
bit 4 EBTR4: Table Read Protection bit(1,3)
1 = Block 4, not protected from table reads executed in other blocks(2)
0 = Block 4, protected from table reads executed in other blocks(2)
bit 3 EBTR3: Table Read Protection bit(3)
1 = Block 3, not protected from table reads executed in other blocks(2)
0 = Block 3, protected from table reads executed in other blocks(2)
bit 2 EBTR2: Table Read Protection bit(3)
1 = Block 2, not protected from table reads executed in other blocks(2)
0 = Block 2, protected from table reads executed in other blocks(2)
bit 1 EBTR1: Table Read Protection bit(3)
1 = Block 1, not protected from table reads executed in other blocks(2)
0 = Block 1, protected from table reads executed in other blocks(2)
bit 0 EBTR0: Table Read Protection bit(3)
1 = Block 0, not protected from table reads executed in other blocks(2)
0 = Block 0, protected from table reads executed in other blocks(2)
Note 1: This bit is available only on PIC18F67K22 and PIC18F87K22 devices.
2: For the memory size of the blocks, see Figure 28-6
3: Enable the corresponding CPx bit to protect the block from external read operations.
2011 Microchip Technology Inc. DS39960C-page 417
PIC18F87K22 FAMILY
REGISTER 28-13: CONFIG7H: CONFIGURATION REGISTER 7 HIGH (BYTE ADDRESS 30000Dh)
U-0 R/C-1 U-0 U-0 U-0 U-0 U-0 U-0
— EBTRB(2) — — — — — —
bit 7 bit 0
Legend: C = Clearable bit
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 Unimplemented: Read as ‘0’
bit 6 EBTRB: Boot Block Table Read Protection bit(2)
1 = Boot block, not protected from table reads executed in other blocks(1)
0 = Boot block, protected from table reads executed in other blocks(1)
bit 5-0 Unimplemented: Read as ‘0’
Note 1: For the memory size of the blocks, see Figure 28-6.
2: Enable the corresponding CPx bit to protect the block from external read operations.
PIC18F87K22 FAMILY
DS39960C-page 418 2011 Microchip Technology Inc.
REGISTER 28-14: DEVID1: DEVICE ID REGISTER 1 FOR THE PIC18F87K22 FAMILY
RRRRRRRR
DEV2 DEV1 DEV0 REV4 REV3 REV2 REV1 REV0
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7-5 DEV<2:0>: Device ID bits
Devices with DEV<10:3> of 0101 0010 (see DEVID2):
010 = PIC18F65K22
000 = PIC18F66K22
101 = PIC18F85K22
011 = PIC18F86K22
Devices with DEV<10:3> of 0101 0001:
000 = PIC18F67K22
010 = PIC18F87K22
bit 4-0 REV<4:0>: Revision ID bits
These bits are used to indicate the device revision.
REGISTER 28-15: DEVID2: DEVICE ID REGISTER 2 FOR THE PIC18F87K22 FAMILY
RRRRRRRR
DEV10(1) DEV9(1) DEV8(1) DEV7(1) DEV6(1) DEV5(1) DEV4(1) DEV3(1)
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7-0 DEV<10:3>: Device ID bits(1)
These bits are used with the DEV<2:0> bits in the Device ID Register 1 to identify the part number.
0101 0010 = PIC18F65K22, PIC18F66K22, PIC18F85K22 and PIC18F86K22
0101 0001 = PIC18F67K22 and PIC18F87K22
Note 1: These values for DEV<10:3> may be shared with other devices. The specific device is always identified by
using the entire DEV<10:0> bit sequence.
2011 Microchip Technology Inc. DS39960C-page 419
PIC18F87K22 FAMILY
28.2 W atchdog Timer (WDT)
For the PIC18F87K22 family of devices, the WDT is
driven by the LF-INTOSC source. When the WDT is
enabled, the clock source is also enabled. The nominal
WDT period is 4 ms and has the same stability as the
LF-INTOSC oscillator.
The 4 ms period of the WDT is multiplied by a 16-bit
postscaler. Any output of the WDT postscaler is
selected by a multiplexer, controlled by bits in
Configuration Register 2H. Available periods range
from 4 ms to 4,194 seconds (about one hour). The
WDT and postscaler are cleared when any of the
following events occur: a SLEEP or CLRWDT instruction
is executed, the IRCF bits (OSCCON<6:4>) are
changed or a clock failure has occurred.
The WDT can be operated in one of four modes as
determined by CONFIG2H<WDTEN<1:0> The four
modes are:
•WDT Enabled
• WDT Disabled
• WDT under software control,
SWDTEN (WDTCON<0>)
•WDT
- Enabled during normal operation
- Disabled during Sleep
FIGURE 28-1: WD T BLOCK DIAGRAM
Note 1: The CLRWDT and SLEEP instructions
clear the WDT and postscaler counts
when executed.
2: Changing the setting of the IRCF bits
(OSCCON<6:4>) clears the WDT and
postscaler counts.
3: When a CLRWDT instruction is executed,
the postscaler count will be cleared.
INTRC Source
WDT
Reset
WDT Counter
Programmable Postscaler
1:1 to 1:1,048,576
Enable WDT
WDTPS<3:0>
CLRWDT
4
Reset
All Device Resets
Sleep
128
Change on IRCF bits
INTRC Source
Enable WDT
SWDTEN
WDTEN<1:0>
WDT Enabled,
SWDTEN Disabled
WDT Controlled with
SWDTEN bit Setting
WDT Disabled in Hardware,
SWDTEN Disabled
WDT Enabled only while
Device is Active, Disabled
Wake-up from
Power-Managed
Modes
WDTEN1
WDTEN0
PIC18F87K22 FAMILY
DS39960C-page 420 2011 Microchip Technology Inc.
28.2.1 CONTROL REGISTER
Register 28-16 shows the WDTCON register. This is a
readable and writable register which contains a control
bit that allows software to override the WDT Enable
Configuration bit, but only if the Configuration bit has
disabled the WDT.
TABLE 28-2: SUMMARY OF WATCHDOG TIMER REGISTERS
REGISTER 28-16: WDTCON: WATCHDOG TIMER CONTROL REGISTER
R/W-0 U-0 R-x R/W-0 U-0 R/W-0 R/W-0 R/W-0
REGSLP —ULPLVLSRETEN
(2) — ULPEN ULPSINK SWDTEN(1)
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7 REGSLP: Regulator Voltage Sleep Enable bit
1 = Regulator goes into Low-Power mode when device’s Sleep mode is enabled
0 = Regulator stays in normal mode when device’s Sleep mode is activated
bit 6 Unimplemented: Read as ‘0’
bit 5 ULPLVL: Ultra Low-Power Wake-up Output bit
Not valid unless ULPEN = 1.
1 = Voltage on RA0 pin > ~ 0.5V
0 = Voltage on RA0 pin < ~ 0.5V.
bit 4 SRETEN: Regulator Voltage Sleep Disable bit(2)
1 = If RETEN (CONFIG1L<0>) = 0 and the regulator is enabled, the device goes into Ultra Low-Power
mode in Sleep
0 = The regulator is on when device’s Sleep mode is enabled and the Low-Power mode is controlled
by REGSLP
bit 3 Unimplemented: Read as ‘0’
bit 2 ULPEN: Ultra Low-Power Wake-up Module Enable bit
1 = Ultra low-power wake-up module is enabled; ULPLVL bit indicates the comparator output
0 = Ultra low-power wake-up module is disabled
bit 1 ULPSINK: Ultra Low-Power Wake-up Current Sink Enable bit
Not valid unless ULPEN = 1.
1 = Ultra low-power wake-up current sink is enabled
0 = Ultra low-power wake-up current sink is disabled
bit 0 SWDTEN: Software Controlled Watchdog Timer Enable bit(1)
1 = Watchdog Timer is on
0 = Watchdog Timer is off
Note 1: This bit has no effect if the Configuration bits, WDTEN<1:0>, are enabled.
2: This bit is available only when ENVREG = 1 and RETEN = 0.
Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
RCON IPEN SBOREN CM RI TO PD POR BOR
WDTCON REGSLP —ULPLVLSRETEN— ULPEN ULPSINK SWDTEN
Legend: — = unimplemented, read as ‘0’. Shaded cells are not used by the Watchdog Timer.
2011 Microchip Technology Inc. DS39960C-page 421
PIC18F87K22 FAMILY
28.3 On-Chip Voltage Regulator
All of the PIC18F87K22 family devices power their core
digital logic at a nominal 3.3V. For designs that are
required to operate at a higher typical voltage, such as
5V, all family devices incorporate two on-chip regula-
tors that allows the device to run its core logic from
VDD. Those regulators are:
• Normal on-chip regulator
• Ultra Low-Power, on-chip regulator
The hardware configuration of these regulators are the
same and are explained in Section 28.3.1 “ Regul ator
Enable/Disable By Hardware”. The regulators’ only
differences relate to when the device enters Sleep, as
explained in Section 28.3.2 “Operation of Regulator
in Sleep”.
28.3.1 REGULATOR ENABLE/DISABLE BY
HARDWARE
The regulator can be enabled or disabled only by hard-
ware. The regulator is controlled by the ENVREG pin
and the VDDCORE/VCAP pin.
28.3.1.1 Regulator Enable Mode
Tying VDD to the pin enables the regulator, which in turn,
provides power to the core from the other VDD pins.
When the regulator is enabled, a low-ESR filter capac-
itor must be connected to the VDDCORE/VCAP pin (see
Figure 28-2). This helps maintain the regulator’s
stability. The recommended value for the filter capacitor
is given in Section 31.2 “DC Characteristics: Power-
Down and Supply Current PIC18F87K22 Family
(Industrial)”.
28.3.1.2 Regulator Disable Mode
If the regulator is disabled by connecting VSS to the
ENVREG pin, the power to the core is supplied directly
by VDD. The voltage levels for VDD must not exceed the
specified VDDCORE levels. In Regulator Disabled mode,
a 0.1 µF capacitor should be connected to the
VDDCORE/VCAP pin (see Figure 28-2).
When the regulator is being used, the overall voltage
budget is very tight. The regulator should operate the
device down to 1.8V. When VDD drops below 3.3V, the
regulator no longer regulates, but the output voltage fol-
lows the input until VDD reaches 1.8V. Below this voltage,
the output of the regulator output may drop to 0V.
FIGURE 28-2: CONNECTIONS FOR THE
ON-CHIP REGULATOR
VDD
ENVREG
VDDCORE/VCAP
VSS
CF
5V
Regul ato r Enabled (ENV REG tie d to VDD):
VDD
ENVREG
VDDCORE/VCAP
VSS
3.3V(1)
Regulator Disabled (ENVREG tied to VSS):
Note 1: These are typical operating voltages. For the
full operating ranges of VDD and VDDCORE,
see Section 31.2 “DC Characteristics:
Power-Down and Supply Current
PIC18F87K22 Family (Industrial) ”.
PIC18F87K22
PIC18F87K22
0.1µF
PIC18F87K22 FAMILY
DS39960C-page 422 2011 Microchip Technology Inc.
28.3.2 OPERATION OF REGULATOR IN
SLEEP
The difference in the two regulators’ operation arises
with Sleep mode. The ultra low-power regulator gives
the device the lowest current in the Regulator Enabled
mode.
The on-chip regulator can go into a lower power mode
when the device goes to Sleep by setting the REGSLP
bit (WDTCON<7>). This puts the regulator in a standby
mode so that the device consumes much less current.
The on-chip regulator can also go into the Ultra Low-
Power mode, which consumes the lowest current
possible with the regulator enabled. This mode is
controlled by the RETEN bit (CONFIG1L<0>) and
SRETEN bit (WDTCON<4>).
The various modes of regulator operation are shown in
Table 28-3.
When the ultra low-power regulator is in Sleep mode,
the internal reference voltages in the chip will be shut
off and any interrupts referring to the internal reference
will not wake up the device. If the BOR or LVD is
enabled, the regulator will keep the internal references
on and the lowest possible current will not be achieved.
When using the ultra low-power regulator in Sleep
mode, the device will take about 250 s typical to start
executing the code after it wakes up.
TABLE 28-3: SLEEP MODE REGULATOR SETTINGS(1)
Regulator Power Mode VREGSLP
WDTCON<7> SRETEN
WDTCON<4> RETEN
CONFIG1L<0>
Enabled Normal Operation (Sleep) 0x1
Enabled Low-Power mode (Sleep) 1x1
Enabled Normal Operation (Sleep) 00x
Enabled Low-Power mode (Sleep) 10x
Enabled Ultra Low-Power mode (Sleep) x10
Note 1: x = Indicates that VIT status is invalid.
2011 Microchip Technology Inc. DS39960C-page 423
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28.4 Two-Speed Start-up
The Two-Speed Start-up feature helps to minimize the
latency period from oscillator start-up to code execution
by allowing the microcontroller to use the INTOSC
(LF-INTOSC, MF-INTOSC, HF-INTOSC) oscillator as a
clock source until the primary clock source is available.
It is enabled by setting the IESO Configuration bit.
Two-Speed Start-up should be enabled only if the
primary oscillator mode is LP, XT or HS (Crystal-Based
modes). Other sources do not require an OST start-up
delay; for these, Two-Speed Start-up should be
disabled.
When enabled, Resets and wake-ups from Sleep mode
cause the device to configure itself to run from the
internal oscillator block as the clock source, following
the time-out of the Power-up Timer after a Power-on
Reset is enabled. This allows almost immediate code
execution while the primary oscillator starts and the
OST is running. Once the OST times out, the device
automatically switches to PRI_RUN mode.
To use a higher clock speed on wake-up, the INTOSC
or postscaler clock sources can be selected to provide
a higher clock speed by setting bits, IRCF<2:0>,
immediately after Reset. For wake-ups from Sleep, the
INTOSC or postscaler clock sources can be selected
by setting the IRCF2:0> bits prior to entering Sleep
mode.
In all other power-managed modes, Two-Speed Start-
up is not used. The device will be clocked by the
currently selected clock source until the primary clock
source becomes available. The setting of the IESO bit
is ignored.
28.4.1 SPECIAL CONSIDERATIONS FOR
USING TWO-SPEED START-UP
While using the INTOSC oscillator in Two-Speed Start-
up, the device still obeys the normal command
sequences for entering power-managed modes,
including multiple SLEEP instructions (refer to
Section 4.1.4 “Multiple Sleep Commands”). In
practice, this means that user code can change the
SCS<1:0> bit settings or issue SLEEP instructions
before the OST times out. This would allow an
application to briefly wake-up, perform routine
“housekeeping” tasks and return to Sleep before the
device starts to operate from the primary oscillator.
User code can also check if the primary clock source is
currently providing the device clocking by checking the
status of the OSTS bit (OSCCON<3>). If the bit is set,
the primary oscillator is providing the clock. Otherwise,
the internal oscillator block is providing the clock during
wake-up from Reset or Sleep mode.
FIGURE 28-3: TIMING TRA NSITION FOR TW O-SPEED START-UP (INTOSC TO HSPLL)
Q1 Q3 Q4
OSC1
Peripheral
Program PC PC + 2
INTOSC
PLL Clock
Q1
PC + 6
Q2
Output
Q3 Q4 Q1
CPU Clock
PC + 4
Clock
Counter
Q2 Q2 Q3
Note 1: TOST = 1024 TOSC; TPLL = 2 ms (approx). These intervals are not shown to scale.
2: Clock transition typically occurs within 2-4 TOSC.
Wake from Interrupt Event
TPLL(1)
12 n-1n
Clock
OSTS bit Set
Transition(2)
Multiplexer
TOST(1)
PIC18F87K22 FAMILY
DS39960C-page 424 2011 Microchip Technology Inc.
28.5 Fail-Safe Clock Monitor
The Fail-Safe Clock Monitor (FSCM) allows the
microcontroller to continue operation in the event of an
external oscillator failure by automatically switching the
device clock to the internal oscillator block. The FSCM
function is enabled by setting the FCMEN Configuration
bit.
When FSCM is enabled, the LF-INTOSC oscillator runs
at all times to monitor clocks to peripherals and provide
a backup clock in the event of a clock failure. Clock
monitoring (shown in Figure 28-4) is accomplished by
creating a sample clock signal, which is the output from
the LF-INTOSC divided by 64. This allows ample time
between FSCM sample clocks for a peripheral clock
edge to occur. The peripheral device clock and the
sample clock are presented as inputs to the Clock
Monitor (CM) latch. The CM is set on the falling edge of
the device clock source, but cleared on the rising edge
of the sample clock.
FIGURE 28-4: FSCM BLOCK DIAGRAM
Clock failure is tested for on the falling edge of the
sample clock. If a sample clock falling edge occurs
while CM is still set, a clock failure has been detected
(Figure 28-5). This causes the following:
• The FSCM generates an oscillator fail interrupt by
setting bit, OSCFIF (PIR2<7>)
• The device clock source switches to the internal
oscillator block (OSCCON is not updated to show
the current clock source – this is the fail-safe
condition)
•The WDT is reset
During switchover, the postscaler frequency from the
internal oscillator block may not be sufficiently stable for
timing-sensitive applications. In these cases, it may be
desirable to select another clock configuration and enter
an alternate power-managed mode. This can be done to
attempt a partial recovery or execute a controlled shut-
down. See Section 4.1.4 “Multiple Sleep Commands”
and Section 28.4.1 “Special Considerations for
Using Two-Speed Start-up” for more details.
To use a higher clock speed on wake-up, the INTOSC
or postscaler clock sources can be selected to provide
a higher clock speed by setting bits, IRCF<2:0>,
immediately after Reset. For wake-ups from Sleep, the
INTOSC or postscaler clock sources can be selected
by setting the IRCF<2:0> bits prior to entering Sleep
mode.
The FSCM will detect only failures of the primary or
secondary clock sources. If the internal oscillator block
fails, no failure would be detected nor would any action
be possible.
28.5.1 FSCM AND THE WATCHDOG TIMER
Both the FSCM and the WDT are clocked by the
INTOSC oscillator. Since the WDT operates with a
separate divider and counter, disabling the WDT has
no effect on the operation of the INTOSC oscillator
when the FSCM is enabled.
As already noted, the clock source is switched to the
INTOSC clock when a clock failure is detected.
Depending on the frequency selected by the
IRCF<2:0> bits, this may mean a substantial change in
the speed of code execution. If the WDT is enabled
with a small prescale value, a decrease in clock speed
allows a WDT time-out to occur and a subsequent
device Reset. For this reason, Fail-Safe Clock events
also reset the WDT and postscaler, allowing it to start
timing from when execution speed was changed and
decreasing the likelihood of an erroneous time-out.
28.5.2 EXITING FAIL-SAFE OPERATION
The Fail-Safe condition is terminated by either a device
Reset or by entering a power-managed mode. On
Reset, the controller starts the primary clock source
specified in Configuration Register 1H (with any
required start-up delays that are required for the
oscillator mode, such as the OST or PLL timer). The
INTOSC multiplexer provides the device clock until the
primary clock source becomes ready (similar to a Two-
Speed Start-up). The clock source is then switched to
the primary clock (indicated by the OSTS bit in the
OSCCON register becoming set). The Fail-Safe Clock
Monitor then resumes monitoring the peripheral clock.
The primary clock source may never become ready
during start-up. In this case, operation is clocked by the
INTOSC multiplexer. The OSCCON register will remain
in its Reset state until a power-managed mode is
entered.
Peripheral
INTRC ÷ 64
S
C
Q
(32 s) 488 Hz
(2.048 ms)
Clock Monitor
Latc h ( C M)
(edge-triggered)
Clock
Failure
Detected
Source
Clock
Q
2011 Microchip Technology Inc. DS39960C-page 425
PIC18F87K22 FAMILY
FIGURE 28-5: FSCM TIMING DIAGRAM
28.5.3 FSCM INTERRUPTS IN
POWER-MANAGED MODES
By entering a power-managed mode, the clock
multiplexer selects the clock source selected by the
OSCCON register. Fail-Safe Clock Monitoring of
the power-managed clock source resumes in the
power-managed mode.
If an oscillator failure occurs during power-managed
operation, the subsequent events depend on whether
or not the oscillator failure interrupt is enabled. If
enabled (OSCFIF = 1), code execution will be clocked
by the INTOSC multiplexer. An automatic transition
back to the failed clock source will not occur.
If the interrupt is disabled, subsequent interrupts while
in Idle mode will cause the CPU to begin executing
instructions while being clocked by the INTOSC
source.
28.5.4 POR OR WAKE FROM SLEEP
The FSCM is designed to detect oscillator failure at any
point after the device has exited Power-on Reset
(POR) or low-power Sleep mode. When the primary
device clock is EC, RC or INTRC modes, monitoring
can begin immediately following these events.
For oscillator modes involving a crystal or resonator
(HS, HSPLL, LP or XT), the situation is somewhat
different. Since the oscillator may require a start-up
time considerably longer than the FCSM sample clock
time, a false clock failure may be detected. To prevent
this, the internal oscillator block is automatically config-
ured as the device clock and functions until the primary
clock is stable (when the OST and PLL timers have
timed out).
This is identical to Two-Speed Start-up mode. Once the
primary clock is stable, the INTOSC returns to its role
as the FSCM source.
As noted in Sect ion 28. 4.1 “Spec ial Cons idera tions
for Using Two-Speed Start-up”, it is also possible to
select another clock configuration and enter an
alternate power-managed mode while waiting for the
primary clock to become stable. When the new power-
managed mode is selected, the primary clock is
disabled.
OSCFIF
CM Output
Device
Clock
Output
Sample Clock
Failure
Detected
Oscillator
Failure
Note: The device clock is normally at a much higher frequency than the sample clock. The relative frequencies in this
example have been chosen for clarity.
(Q)
CM Test CM Test CM Test
Note: The same logic that prevents false oscilla-
tor failure interrupts on POR, or wake from
Sleep, also prevents the detection of the
oscillator’s failure to start at all following
these events. This can be avoided by
monitoring the OSTS bit and using a
timing routine to determine if the oscillator
is taking too long to start. Even so, no
oscillator failure interrupt will be flagged.
PIC18F87K22 FAMILY
DS39960C-page 426 2011 Microchip Technology Inc.
28.6 Program Verification and
Code Protection
The user program memory is divided into four blocks
for the PIC18FX5K22 and PIC18FX6K22 devices and
eight blocks for PIC18FX7K22 devices. One of these is
a boot block of 1 or 2 Kbytes. The remainder of the
memory is divided into blocks on binary boundaries.
Each of the blocks has three code protection bits
associated with them. They are:
• Code-Protect bit (CPx)
• Write-Protect bit (WRTx)
• External Block Table Read bit (EBTRx)
Figure 28-6 shows the program memory organization for
48, 64, 96 and 128 Kbyte devices and the specific code
protection bit associated with each block. The actual
locations of the bits are summarized in Table 28-4.
FIGURE 28-6: CODE-P ROTECTED PROGRAM MEMORY FOR THE PIC18F87K22 FAMILY
000000h
200000h
3FFFFFh
01FFFFh
Note 1: Sizes of memory areas are not to scale.
2: Boot block size is determined by the BBSIZ0 bit (CONFIG4L<4>).
Code Memory
Unimplemented
Read as ‘0’
Configuration
and ID
Space
Device/Memory Size
Address
PIC18FX7K22 PIC18FX6K22 PIC18FX5K22
BBSIZ =
1
BBSIZ =
0
BBSIZ =
1
BBSIZ =
0
BBSIZ =
1
BBSIZ =
0
Boot
Block
2kW
Boot
Block
Boot
Block
2kW
Boot
Block
Boot
Block
2kW
Boot
Block
0000h
Block 0
7kW
Block 0
7kW
Block 0
3kW
0800h
Block 0
6kW
Block 0
6kW
Block 0
2kW
1000h
17FFh
Block 1
4kW
Block 1
4kW
1800
3FFF
Block 1
8kW
Block 1
8kW
Block 1
8kW
Block 1
8kW
Block 2
4kW
Block 2
4kW
4000h
5FFFh
Block 3
4kW
Block 3
4kW
6000h
7FFF
Block 2
8kW
Block 2
8kW
Block 2
8kW
Block 2
8kW
8000h
BFFFh
Block 3
8kW
Block 3
8kW
Block 3
8kW
Block 3
8kW
C000h
FFFFh
Block 4
8kW
Block 4
8kW
10000h
13FFFh
Block 5
8kW
Block 5
8kW
14000h
17FFFh
Block 6
8kW
Block 6
8kW
18000h
1BFFFh
Block 7
8kW
Block 7
8kW
1C000h
1FFFFh
2011 Microchip Technology Inc. DS39960C-page 427
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TABLE 28-4: SUMMARY OF CODE PROTECTION REGISTERS
28.6.1 PROGRAM MEMORY
CODE PROTECTION
The program memory may be read to, or written from,
any location using the table read and table write
instructions. The Device ID may be read with table
reads. The Configuration registers may be read and
written with the table read and table write instructions.
In normal execution mode, the CPx bits have no direct
effect. CPx bits inhibit external reads and writes. A block
of user memory may be protected from table writes if the
WRTx Configuration bit is ‘0’.
The EBTRx bits control table reads. For a block of user
memory, with the EBTRx bit set to ‘0’, a table read
instruction that executes from within that block is allowed
to read. A table read instruction that executes from a
location outside of that block is not allowed to read and
will result in reading ‘0’s. Figures 28-7 through 28-9
illustrate table write and table read protection.
FIGURE 28-7: TABLE WRITE (WRTx) DISALLOWED
File Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
300008h CONFIG5L CP7(1) CP6(1) CP5(1) CP4(1) CP3 CP2 CP1 CP0
300009h CONFIG5H CPD CPB — — — — — —
30000Ah CONFIG6L WRT7(1) WRT6(1) WRT5(1) WRT4(1) WRT3 WRT2 WRT1 WRT0
30000Bh CONFIG6H WRTD WRTB WRTC — — — — —
30000Ch CONFIG7L EBTR7(1) EBTR6(1) EBTR5(1) EBTR4(1) EBTR3 EBTR2 EBTR1 EBTR0
30000Dh CONFIG7H — EBTRB — — — — — —
Legend: Shaded cells are unimplemented.
Note 1: This bit is available only on the PIC18F67K22 and PIC18F87K22 devices.
Note: Code protection bits may only be written
to a ‘0’ from a ‘1’ state. It is not possible to
write a ‘1’ to a bit in the ‘0’ state. Code
protection bits are only set to ‘1’ by a full
chip erase or block erase function. The full
chip erase and block erase functions can
only be initiated via ICSP or an external
programmer. Refer to the device
programming specification for more
information.
000000h
0007FFh
000800h
003FFFh
004000h
007FFFh
008000h
00BFFFh
00C000h
00FFFFh
WRTB, EBTRB = 11
WRT0, EBTR0 = 01
WRT1, EBTR1 = 11
WRT2, EBTR2 = 11
WRT3, EBTR3 = 11
TBLWT*
TBLPTR = 0008FFh
PC = 003FFEh
TBLWT*
PC = 00BFFEh
Register Values Program Memory Configuration Bit Settings
Results: All table writes are disabled to Blockn whenever WRTx = 0.
PIC18F87K22 FAMILY
DS39960C-page 428 2011 Microchip Technology Inc.
FIGURE 28-8: EX TERN AL BLOCK TABLE READ (EBTRx) DISALLOWED
FIGURE 28-9: EX TERN AL BLOCK TABLE READ (EBTRx) ALLOWED
WRTB, EBTRB = 11
WRT0, EBTR0 = 10
WRT1, EBTR1 = 11
WRT2, EBTR2 = 11
WRT3, EBTR3 = 11
TBLRD*
TBLPTR = 0008FFh
PC = 007FFEh
Results: All table reads from external blocks to Blockn are disabled whenever EBTRx = 0.
The TABLAT register returns a value of ‘0’.
Register Values Program Memory Configuration Bit Settings
000000h
0007FFh
000800h
003FFFh
004000h
007FFFh
008000h
00BFFFh
00C000h
00FFFFh
WRTB, EBTRB = 11
WRT0, EBTR0 = 10
WRT1, EBTR1 = 11
WRT2, EBTR2 = 11
WRT3, EBTR3 = 11
TBLRD*
TBLPTR = 0008FFh
PC = 003FFEh
Register Values Program Memory Configuration Bit Settings
Results: Table reads permitted within Blockn, even when EBTRBx = 0.
The TABLAT register returns the value of the data at the location, TBLPTR.
000000h
0007FFh
000800h
003FFFh
004000h
007FFFh
008000h
00BFFFh
00C000h
00FFFFh
2011 Microchip Technology Inc. DS39960C-page 429
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28.6.2 DATA EEPROM
CODE PROTECTION
The entire data EEPROM is protected from external
reads and writes by two bits: CPD and WRTD. CPD
inhibits external reads and writes of data EEPROM.
WRTD inhibits internal and external writes to data
EEPROM. The CPU can always read data EEPROM
under normal operation, regardless of the protection bit
settings.
28.6.3 CONFIGURATION REGISTER
PROTECTION
The Configuration registers can be write-protected.
The WRTC bit controls protection of the Configuration
registers. In normal execution mode, the WRTC bit is
readable only. WRTC can only be written via ICSP or
an external programmer.
28.7 ID Locations
Eight memory locations (200000h-200007h) are
designated as ID locations, where the user can store
checksum or other code identification numbers. These
locations are both readable and writable during normal
execution through the TBLRD and TBLWT instructions
or during program/verify. The ID locations can be read
when the device is code-protected.
28.8 In-Circuit Serial Programming
The PIC18F87K22 family of devices can be serially
programmed while in the end application circuit. This is
simply done with two lines for clock and data and three
other lines for power, ground and the programming
voltage. This allows customers to manufacture boards
with unprogrammed devices and then program the
microcontroller just before shipping the product. This
also allows the most recent firmware or a custom
firmware to be programmed.
For the various programming modes, see the
programming specification
28.9 In-Circuit Debugger
When the DEBUG Configuration bit is programmed to
a ‘0’, the In-Circuit Debugger functionality is enabled.
This function allows simple debugging functions when
used with MPLAB® IDE. When the microcontroller has
this feature enabled, some resources are not available
for general use. Ta bl e 2 8 - 5 shows which resources are
required by the background debugger.
TABLE 28-5: DEBUGGER RESOURCES
To use the In-Circuit Debugger function of the micro-
controller, the design must implement In-Circuit Serial
Programming connections to MCLR/RG5/VPP, VDD,
VSS, RB7 and RB6. This will interface to the In-Circuit
Debugger module available from Microchip or one of
the third-party development tool companies.
I/O Pins: RB6, RB7
Stack: Two levels
Program Memory: 512 bytes
Data Memory: 10 bytes
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NOTES:
2011 Microchip Technology Inc. DS39960C-page 431
PIC18F87K22 FAMILY
29.0 INSTRUCTION SET SUMMARY
The PIC18F87K22 family of devices incorporates the
standard set of 75 PIC18 core instructions, as well as
an extended set of 8 new instructions for the optimiza-
tion of code that is recursive or that utilizes a software
stack. The extended set is discussed later in this
section.
29.1 Standard Instruction Set
The standard PIC18 MCU instruction set adds many
enhancements to the previous PIC® MCU instruction
sets, while maintaining an easy migration from these
PIC MCU instruction sets. Most instructions are a
single program memory word (16 bits), but there are
four instructions that require two program memory
locations.
Each single-word instruction is a 16-bit word divided
into an opcode, which specifies the instruction type and
one or more operands, which further specify the
operation of the instruction.
The instruction set is highly orthogonal and is grouped
into four basic categories:
•Byte-oriented operations
•Bit-oriented operations
•Literal operations
•Control operations
The PIC18 instruction set summary in Table 29-2 lists
byte-oriented, bit-oriented, literal and control
operations. Table 29-1 shows the opcode field
descriptions.
Most byte-oriented instructions have three operands:
1. The file register (specified by ‘f’)
2. The destination of the result (specified by ‘d’)
3. The accessed memory (specified by ‘a’)
The file register designator, ‘f’, specifies which file reg-
ister is to be used by the instruction. The destination
designator, ‘d’, specifies where the result of the
operation is to be placed. If ‘d’ is zero, the result is
placed in the WREG register. If ‘d’ is one, the result is
placed in the file register specified in the instruction.
All bit-oriented instructions have three operands:
1. The file register (specified by ‘f’)
2. The bit in the file register (specified by ‘b’)
3. The accessed memory (specified by ‘a’)
The bit field designator, ‘b’, selects the number of the bit
affected by the operation, while the file register desig-
nator, ‘f’, represents the number of the file in which the
bit is located.
The literal instructions may use some of the following
operands:
• A literal value to be loaded into a file register
(specified by ‘k’)
• The desired FSR register to load the literal value
into (specified by ‘f’)
• No operand required
(specified by ‘—’)
The control instructions may use some of the following
operands:
• A program memory address (specified by ‘n’)
• The mode of the CALL or RETURN instructions
(specified by ‘s’)
• The mode of the table read and table write
instructions (specified by ‘m’)
• No operand required
(specified by ‘—’)
All instructions are a single word, except for four
double-word instructions. These instructions were
made double-word to contain the required information
in 32 bits. In the second word, the 4 MSbs are ‘1’s. If
this second word is executed as an instruction (by
itself), it will execute as a NOP.
All single-word instructions are executed in a single
instruction cycle, unless a conditional test is true or the
program counter is changed as a result of the instruc-
tion. In these cases, the execution takes two instruction
cycles with the additional instruction cycle(s) executed
as a NOP.
The double-word instructions execute in two instruction
cycles.
One instruction cycle consists of four oscillator periods.
Thus, for an oscillator frequency of 4 MHz, the normal
instruction execution time is 1 s. If a conditional test is
true, or the program counter is changed as a result of
an instruction, the instruction execution time is 2 s.
Two-word branch instructions (if true) would take 3 s.
Figure 29-1 shows the general formats that the instruc-
tions can have. All examples use the convention ‘nnh’
to represent a hexadecimal number.
The Instruction Set Summary, shown in Table 29-2,
lists the standard instructions recognized by the
Microchip MPASMTM Assembler.
Section 29.1.1 “Standard Instruction Set” provides
a description of each instruction.
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DS39960C-page 432 2011 Microchip Technology Inc.
TABLE 29-1: OPCODE FIELD DESCRIPTIONS
Field Description
aRAM access bit:
a = 0: RAM location in Access RAM (BSR register is ignored)
a = 1: RAM bank is specified by BSR register
bbb Bit address within an 8-bit file register (0 to 7).
BSR Bank Select Register. Used to select the current RAM bank.
C, DC, Z, OV, N ALU Status bits: Carry, Digit Carry, Zero, Overflow, Negative.
dDestination select bit:
d = 0: store result in WREG
d = 1: store result in file register f
dest Destination: either the WREG register or the specified register file location.
f8-bit register file address (00h to FFh), or 2-bit FSR designator (0h to 3h).
fs12-bit register file address (000h to FFFh). This is the source address.
fd12-bit register file address (000h to FFFh). This is the destination address.
GIE Global Interrupt Enable bit.
kLiteral field, constant data or label (may be either an 8-bit, 12-bit or a 20-bit value).
label Label name.
mm The mode of the TBLPTR register for the table read and table write instructions.
Only used with table read and table write instructions:
*No Change to register (such as TBLPTR with table reads and writes)
*+ Post-Increment register (such as TBLPTR with table reads and writes)
*- Post-Decrement register (such as TBLPTR with table reads and writes)
+* Pre-Increment register (such as TBLPTR with table reads and writes)
nThe relative address (2’s complement number) for relative branch instructions or the direct address for
Call/Branch and Return instructions.
PC Program Counter.
PCL Program Counter Low Byte.
PCH Program Counter High Byte.
PCLATH Program Counter High Byte Latch.
PCLATU Program Counter Upper Byte Latch.
PD Power-Down bit.
PRODH Product of Multiply High Byte.
PRODL Product of Multiply Low Byte.
sFast Call/Return mode select bit:
s = 0: do not update into/from shadow registers
s = 1: certain registers loaded into/from shadow registers (Fast mode)
TBLPTR 21-bit Table Pointer (points to a Program Memory location).
TABLAT 8-bit Table Latch.
TO Time-out bit.
TOS Top-of-Stack.
uUnused or Unchanged.
WDT Watchdog Timer.
WREG Working register (accumulator).
xDon’t care (‘0’ or ‘1’). The assembler will generate code with x = 0. It is the recommended form of use for
compatibility with all Microchip software tools.
zs7-bit offset value for Indirect Addressing of register files (source).
zd7-bit offset value for Indirect Addressing of register files (destination).
{ } Optional argument.
[text] Indicates an Indexed Address.
(text) The contents of text.
[expr]<n> Specifies bit n of the register indicated by the pointer expr.
Assigned to.
< > Register bit field.
In the set of.
italics User-defined term (font is Courier New).
2011 Microchip Technology Inc. DS39960C-page 433
PIC18F87K22 FAMILY
FIGURE 29-1: GENE RAL FORMAT FOR INSTRUCTIONS
Byte-oriented file register operations
15 10 9 8 7 0
d = 0 for result destination to be WREG register
OPCODE d a f (FILE #)
d = 1 for result destination to be file register (f)
a = 0 to force Access Bank
Bit-oriented file register operations
15 12 11 9 8 7 0
OPCODE b (BIT #) a f (FILE #)
b = 3-bit position of bit in file register (f)
Literal operations
15 8 7 0
OPCODE k (literal)
k = 8-bit immediate value
Byte to Byte move operations (2-word)
15 12 11 0
OPCODE f (Source FILE #)
CALL, GOTO and Branch operations
15 8 7 0
OPCODE n<7:0> (literal)
n = 20-bit immediate value
a = 1 for BSR to select bank
f = 8-bit file register address
a = 0 to force Access Bank
a = 1 for BSR to select bank
f = 8-bit file register address
15 12 11 0
1111 n<19:8> (literal)
15 12 11 0
1111 f (Destination FILE #)
f = 12-bit file register address
Control operations
Example Instruction
ADDWF MYREG, W, B
MOVFF MYREG1, MYREG2
BSF MYREG, bit, B
MOVLW 7Fh
GOTO Label
15 8 7 0
OPCODE S n<7:0> (literal)
15 12 11 0
1111 n<19:8> (literal)
CALL MYFUNC
15 11 10 0
OPCODE n<10:0> (literal)
S = Fast bit
BRA MYFUNC
15 8 7 0
OPCODE n<7:0> (literal) BC MYFUNC
PIC18F87K22 FAMILY
DS39960C-page 434 2011 Microchip Technology Inc.
TABLE 29-2: PIC18F87K22 FAMILY INSTRUCTION SET
Mnemonic,
Operands Description Cycles 16-Bit Instruction Word Status
Affected Notes
MSb LSb
BYTE-ORIENTED OPERAT IONS
ADDWF
ADDWFC
ANDWF
CLRF
COMF
CPFSEQ
CPFSGT
CPFSLT
DECF
DECFSZ
DCFSNZ
INCF
INCFSZ
INFSNZ
IORWF
MOVF
MOVFF
MOVWF
MULWF
NEGF
RLCF
RLNCF
RRCF
RRNCF
SETF
SUBFWB
SUBWF
SUBWFB
SWAPF
TSTFSZ
XORWF
f, d, a
f, d, a
f, d, a
f, a
f, d, a
f, a
f, a
f, a
f, d, a
f, d, a
f, d, a
f, d, a
f, d, a
f, d, a
f, d, a
f, d, a
fs, fd
f, a
f, a
f, a
f, d, a
f, d, a
f, d, a
f, d, a
f, a
f, d, a
f, d, a
f, d, a
f, d, a
f, a
f, d, a
Add WREG and f
Add WREG and Carry bit to f
AND WREG with f
Clear f
Complement f
Compare f with WREG, Skip =
Compare f with WREG, Skip >
Compare f with WREG, Skip <
Decrement f
Decrement f, Skip if 0
Decrement f, Skip if Not 0
Increment f
Increment f, Skip if 0
Increment f, Skip if Not 0
Inclusive OR WREG with f
Move f
Move fs (source) to 1st word
fd (destination) 2nd word
Move WREG to f
Multiply WREG with f
Negate f
Rotate Left f through Carry
Rotate Left f (No Carry)
Rotate Right f through Carry
Rotate Right f (No Carry)
Set f
Subtract f from WREG with
Borrow
Subtract WREG from f
Subtract WREG from f with
Borrow
Swap Nibbles in f
Test f, Skip if 0
Exclusive OR WREG with f
1
1
1
1
1
1 (2 or 3)
1 (2 or 3)
1 (2 or 3)
1
1 (2 or 3)
1 (2 or 3)
1
1 (2 or 3)
1 (2 or 3)
1
1
2
1
1
1
1
1
1
1
1
1
1
1
1
1 (2 or 3)
1
0010
0010
0001
0110
0001
0110
0110
0110
0000
0010
0100
0010
0011
0100
0001
0101
1100
1111
0110
0000
0110
0011
0100
0011
0100
0110
0101
0101
0101
0011
0110
0001
01da
00da
01da
101a
11da
001a
010a
000a
01da
11da
11da
10da
11da
10da
00da
00da
ffff
ffff
111a
001a
110a
01da
01da
00da
00da
100a
01da
11da
10da
10da
011a
10da
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
C, DC, Z, OV, N
C, DC, Z, OV, N
Z, N
Z
Z, N
None
None
None
C, DC, Z, OV, N
None
None
C, DC, Z, OV, N
None
None
Z, N
Z, N
None
None
None
C, DC, Z, OV, N
C, Z, N
Z, N
C, Z, N
Z, N
None
C, DC, Z, OV, N
C, DC, Z, OV, N
C, DC, Z, OV, N
None
None
Z, N
1, 2
1, 2
1,2
2
1, 2
4
4
1, 2
1, 2, 3, 4
1, 2, 3, 4
1, 2
1, 2, 3, 4
4
1, 2
1, 2
1
1, 2
1, 2
1, 2
1, 2
4
1, 2
Note 1: When a PORT register is modified as a function of itself (e.g., MOVF PORTB, 1, 0), the value used will be that
value present on the pins themselves. For example, if the data latch is ‘1’ for a pin configured as input and is
driven low by an external device, the data will be written back with a ‘0’.
2: If this instruction is executed on the TMR0 register (and, where applicable, d = 1), the prescaler will be cleared
if assigned.
3: If the Program Counter (PC) is modified or a conditional test is true, the instruction requires two cycles. The
second cycle is executed as a NOP.
4: Some instructions are two-word instructions. The second word of these instructions will be executed as a NOP
unless the first word of the instruction retrieves the information embedded in these 16 bits. This ensures that all
program memory locations have a valid instruction.
2011 Microchip Technology Inc. DS39960C-page 435
PIC18F87K22 FAMILY
BIT-ORIENTED OPERATIONS
BCF
BSF
BTFSC
BTFSS
BTG
f, b, a
f, b, a
f, b, a
f, b, a
f, b, a
Bit Clear f
Bit Set f
Bit Test f, Skip if Clear
Bit Test f, Skip if Set
Bit Toggle f
1
1
1 (2 or 3)
1 (2 or 3)
1
1001
1000
1011
1010
0111
bbba
bbba
bbba
bbba
bbba
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
None
None
None
None
None
1, 2
1, 2
3, 4
3, 4
1, 2
CONTROL OPERATIONS
BC
BN
BNC
BNN
BNOV
BNZ
BOV
BRA
BZ
CALL
CLRWDT
DAW
GOTO
NOP
NOP
POP
PUSH
RCALL
RESET
RETFIE
RETLW
RETURN
SLEEP
n
n
n
n
n
n
n
n
n
n, s
—
—
n
—
—
—
—
n
s
k
s
—
Branch if Carry
Branch if Negative
Branch if Not Carry
Branch if Not Negative
Branch if Not Overflow
Branch if Not Zero
Branch if Overflow
Branch Unconditionally
Branch if Zero
Call Subroutine 1st word
2nd word
Clear Watchdog Timer
Decimal Adjust WREG
Go to Address 1st word
2nd word
No Operation
No Operation
Pop Top of Return Stack (TOS)
Push Top of Return Stack (TOS)
Relative Call
Software Device Reset
Return from Interrupt Enable
Return with Literal in WREG
Return from Subroutine
Go into Standby mode
1 (2)
1 (2)
1 (2)
1 (2)
1 (2)
1 (2)
1 (2)
2
1 (2)
2
1
1
2
1
1
1
1
2
1
2
2
2
1
1110
1110
1110
1110
1110
1110
1110
1101
1110
1110
1111
0000
0000
1110
1111
0000
1111
0000
0000
1101
0000
0000
0000
0000
0000
0010
0110
0011
0111
0101
0001
0100
0nnn
0000
110s
kkkk
0000
0000
1111
kkkk
0000
xxxx
0000
0000
1nnn
0000
0000
1100
0000
0000
nnnn
nnnn
nnnn
nnnn
nnnn
nnnn
nnnn
nnnn
nnnn
kkkk
kkkk
0000
0000
kkkk
kkkk
0000
xxxx
0000
0000
nnnn
1111
0001
kkkk
0001
0000
nnnn
nnnn
nnnn
nnnn
nnnn
nnnn
nnnn
nnnn
nnnn
kkkk
kkkk
0100
0111
kkkk
kkkk
0000
xxxx
0110
0101
nnnn
1111
000s
kkkk
001s
0011
None
None
None
None
None
None
None
None
None
None
TO, PD
C
None
None
None
None
None
None
All
GIE/GIEH,
PEIE/GIEL
None
None
TO, PD
4
TABLE 29-2: PIC18F87K22 FAMILY INSTRUCTION SET (CONTINUED)
Mnemonic,
Operands Description Cycles 16-Bit Instruction Word Status
Affected Notes
MSb LSb
Note 1: When a PORT register is modified as a function of itself (e.g., MOVF PORTB, 1, 0), the value used will be that
value present on the pins themselves. For example, if the data latch is ‘1’ for a pin configured as input and is
driven low by an external device, the data will be written back with a ‘0’.
2: If this instruction is executed on the TMR0 register (and, where applicable, d = 1), the prescaler will be cleared
if assigned.
3: If the Program Counter (PC) is modified or a conditional test is true, the instruction requires two cycles. The
second cycle is executed as a NOP.
4: Some instructions are two-word instructions. The second word of these instructions will be executed as a NOP
unless the first word of the instruction retrieves the information embedded in these 16 bits. This ensures that all
program memory locations have a valid instruction.
PIC18F87K22 FAMILY
DS39960C-page 436 2011 Microchip Technology Inc.
LITERAL OPERATIONS
ADDLW
ANDLW
IORLW
LFSR
MOVLB
MOVLW
MULLW
RETLW
SUBLW
XORLW
k
k
k
f, k
k
k
k
k
k
k
Add Literal and WREG
AND Literal with WREG
Inclusive OR Literal with WREG
Move literal (12-bit) 2nd word
to FSR(f) 1st word
Move Literal to BSR<3:0>
Move Literal to WREG
Multiply Literal with WREG
Return with Literal in WREG
Subtract WREG from Literal
Exclusive OR Literal with WREG
1
1
1
2
1
1
1
2
1
1
0000
0000
0000
1110
1111
0000
0000
0000
0000
0000
0000
1111
1011
1001
1110
0000
0001
1110
1101
1100
1000
1010
kkkk
kkkk
kkkk
00ff
kkkk
0000
kkkk
kkkk
kkkk
kkkk
kkkk
kkkk
kkkk
kkkk
kkkk
kkkk
kkkk
kkkk
kkkk
kkkk
kkkk
kkkk
C, DC, Z, OV, N
Z, N
Z, N
None
None
None
None
None
C, DC, Z, OV, N
Z, N
DATA MEMORY PROGRAM MEMORY OPERATIONS
TBLRD*
TBLRD*+
TBLRD*-
TBLRD+*
TBLWT*
TBLWT*+
TBLWT*-
TBLWT+*
Table Read
Table Read with Post-Increment
Table Read with Post-Decrement
Table Read with Pre-Increment
Table Write
Table Write with Post-Increment
Table Write with Post-Decrement
Table Write with Pre-Increment
2
2
0000
0000
0000
0000
0000
0000
0000
0000
0000
0000
0000
0000
0000
0000
0000
0000
0000
0000
0000
0000
0000
0000
0000
0000
1000
1001
1010
1011
1100
1101
1110
1111
None
None
None
None
None
None
None
None
TABLE 29-2: PIC18F87K22 FAMILY INSTRUCTION SET (CONTINUED)
Mnemonic,
Operands Description Cycles 16-Bit Instruction Word Status
Affected Notes
MSb LSb
Note 1: When a PORT register is modified as a function of itself (e.g., MOVF PORTB, 1, 0), the value used will be that
value present on the pins themselves. For example, if the data latch is ‘1’ for a pin configured as input and is
driven low by an external device, the data will be written back with a ‘0’.
2: If this instruction is executed on the TMR0 register (and, where applicable, d = 1), the prescaler will be cleared
if assigned.
3: If the Program Counter (PC) is modified or a conditional test is true, the instruction requires two cycles. The
second cycle is executed as a NOP.
4: Some instructions are two-word instructions. The second word of these instructions will be executed as a NOP
unless the first word of the instruction retrieves the information embedded in these 16 bits. This ensures that all
program memory locations have a valid instruction.
2011 Microchip Technology Inc. DS39960C-page 437
PIC18F87K22 FAMILY
29.1.1 STANDARD INSTRUCTION SET
ADDLW ADD Literal to W
Syntax: ADDLW k
Operands: 0 k 255
Operation: (W) + k W
Status Affected: N, OV, C, DC, Z
Encoding: 0000 1111 kkkk kkkk
Description: The contents of W are added to the
8-bit literal ‘k’ and the result is placed in
W.
Words: 1
Cycles: 1
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read
literal ‘k’
Process
Data
Write to
W
Example: ADDLW 15h
Before Instruction
W = 10h
After Instruction
W = 25h
ADDWF ADD W to f
Syntax: ADDWF f {,d {,a}}
Operands: 0 f 255
d [0,1]
a [0,1]
Operation: (W) + (f) dest
Status Affected: N, OV, C, DC, Z
Encoding: 0010 01da ffff ffff
Description: Add W to register ‘f’. If ‘d’ is ‘0’, the
result is stored in W. If ‘d’ is ‘1’, the
result is stored back in register ‘f’.
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank.
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f 95 (5Fh). See
Section 29.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Index e d
Literal Offset Mode” for details.
Words: 1
Cycles: 1
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read
register ‘f’
Process
Data
Write to
destination
Example: ADDWF REG, 0, 0
Before Instruction
W = 17h
REG = 0C2h
After Instruction
W = 0D9h
REG = 0C2h
Note: All PIC18 instructions may take an optional label argument preceding the instruction mnemonic for use in
symbolic addressing. If a label is used, the instruction format then becomes: {label} instruction argument(s).
PIC18F87K22 FAMILY
DS39960C-page 438 2011 Microchip Technology Inc.
ADDWFC ADD W and Carry bit to f
Syntax: ADDWFC f {,d {,a}}
Operands: 0 f 255
d [0,1]
a [0,1]
Operation: (W) + (f) + (C) dest
Status Affected: N,OV, C, DC, Z
Encoding: 0010 00da ffff ffff
Description: Add W, the Carry flag and data memory
location ‘f’. If ‘d’ is ‘0’, the result is
placed in W. If ‘d’ is ‘1’, the result is
placed in data memory location ‘f’.
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank.
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f 95 (5Fh). See
Section 29.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
Words: 1
Cycles: 1
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read
register ‘f’
Process
Data
Write to
destination
Example: ADDWFC REG, 0, 1
Before Instruction
Carry bit = 1
REG = 02h
W=4Dh
After Instruction
Carry bit = 0
REG = 02h
W = 50h
ANDLW AND Literal with W
Syntax: ANDLW k
Operands: 0 k 255
Operation: (W) .AND. k W
Status Affected: N, Z
Encoding: 0000 1011 kkkk kkkk
Description: The contents of W are ANDed with the
8-bit literal ‘k’. The result is placed in W.
Words: 1
Cycles: 1
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read literal
‘k’
Process
Data
Write to
W
Example: ANDLW 05Fh
Before Instruction
W=A3h
After Instruction
W = 03h
2011 Microchip Technology Inc. DS39960C-page 439
PIC18F87K22 FAMILY
ANDWF AND W with f
Syntax: ANDWF f {,d {,a}}
Operands: 0 f 255
d [0,1]
a [0,1]
Operation: (W) .AND. (f) dest
Status Affected: N, Z
Encoding: 0001 01da ffff ffff
Description: The contents of W are ANDed with
register ‘f’. If ‘d’ is ‘0’, the result is stored
in W. If ‘d’ is ‘1’, the result is stored back
in register ‘f’.
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank.
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f 95 (5Fh). See
Section 29.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
Words: 1
Cycles: 1
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read
register ‘f’
Process
Data
Write to
destination
Example: ANDWF REG, 0, 0
Before Instruction
W = 17h
REG = C2h
After Instruction
W = 02h
REG = C2h
BC Branch if Carry
Syntax: BC n
Operands: -128 n 127
Operation: if Carry bit is ‘1’,
(PC) + 2 + 2n PC
Status Affected: None
Encoding: 1110 0010 nnnn nnnn
Description: If the Carry bit is ’1’, then the program
will branch.
The 2’s complement number ‘2n’ is
added to the PC. Since the PC will have
incremented to fetch the next
instruction, the new address will be
PC + 2 + 2n. This instruction is then a
two-cycle instruction.
Words: 1
Cycles: 1(2)
Q Cycle Activity:
If Jump:
Q1 Q2 Q3 Q4
Decode Read literal
‘n’
Process
Data
Write to
PC
No
operation
No
operation
No
operation
No
operation
If No Jump:
Q1 Q2 Q3 Q4
Decode Read literal
‘n’
Process
Data
No
operation
Example: HERE BC 5
Before Instruction
PC = address (HERE)
After Instruction
If Carry = 1;
PC = address (HERE + 12)
If Carry = 0;
PC = address (HERE + 2)
PIC18F87K22 FAMILY
DS39960C-page 440 2011 Microchip Technology Inc.
BCF Bit Clear f
Syntax: BCF f, b {,a}
Operands: 0 f 255
0 b 7
a [0,1]
Operation: 0 f<b>
Status Affected: None
Encoding: 1001 bbba ffff ffff
Description: Bit ‘b’ in register ‘f’ is cleared.
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank.
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f 95 (5Fh). See
Section 29.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
Words: 1
Cycles: 1
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read
register ‘f’
Process
Data
Write
register ‘f’
Example: BCF FLAG_REG, 7, 0
Before Instruction
FLAG_REG = C7h
After Instruction
FLAG_REG = 47h
BN Branch if Negative
Syntax: BN n
Operands: -128 n 127
Operation: if Negative bit is ‘1’,
(PC) + 2 + 2n PC
Status Affected: None
Encoding: 1110 0110 nnnn nnnn
Description: If the Negative bit is ‘1’, then the
program will branch.
The 2’s complement number ‘2n’ is
added to the PC. Since the PC will have
incremented to fetch the next
instruction, the new address will be
PC + 2 + 2n. This instruction is then a
two-cycle instruction.
Words: 1
Cycles: 1(2)
Q Cycle Activity:
If Jump:
Q1 Q2 Q3 Q4
Decode Read literal
‘n’
Process
Data
Write to
PC
No
operation
No
operation
No
operation
No
operation
If No Jump:
Q1 Q2 Q3 Q4
Decode Read literal
‘n’
Process
Data
No
operation
Example: HERE BN Jump
Before Instruction
PC = address (HERE)
After Instruction
If Negative = 1;
PC = address
(Jump)
If Negative = 0;
PC = address
(HERE + 2)
2011 Microchip Technology Inc. DS39960C-page 441
PIC18F87K22 FAMILY
BNC Branch if Not Carry
Syntax: BNC n
Operands: -128 n 127
Operation: if Carry bit is ‘0’,
(PC) + 2 + 2n PC
Status Affected: None
Encoding: 1110 0011 nnnn nnnn
Description: If the Carry bit is ‘0’, then the program
will branch.
The 2’s complement number ‘2n’ is
added to the PC. Since the PC will have
incremented to fetch the next
instruction, the new address will be
PC + 2 + 2n. This instruction is then a
two-cycle instruction.
Words: 1
Cycles: 1(2)
Q Cycle Activity:
If Jump:
Q1 Q2 Q3 Q4
Decode Read literal
‘n’
Process
Data
Write to
PC
No
operation
No
operation
No
operation
No
operation
If No Jump:
Q1 Q2 Q3 Q4
Decode Read literal
‘n’
Process
Data
No
operation
Example: HERE BNC Jump
Before Instruction
PC = address (HERE)
After Instruction
If Carry = 0;
PC = address
(Jump)
If Carry = 1;
PC = address (HERE + 2)
BNN Branch if Not Negative
Syntax: BNN n
Operands: -128 n 127
Operation: if Negative bit is ‘0’,
(PC) + 2 + 2n PC
Status Affected: None
Encoding: 1110 0111 nnnn nnnn
Description: If the Negative bit is ‘0’, then the
program will branch.
The 2’s complement number ‘2n’ is
added to the PC. Since the PC will have
incremented to fetch the next
instruction, the new address will be
PC + 2 + 2n. This instruction is then a
two-cycle instruction.
Words: 1
Cycles: 1(2)
Q Cycle Activity:
If Jump:
Q1 Q2 Q3 Q4
Decode Read literal
‘n’
Process
Data
Write to
PC
No
operation
No
operation
No
operation
No
operation
If No Jump:
Q1 Q2 Q3 Q4
Decode Read literal
‘n’
Process
Data
No
operation
Example: HERE BNN Jump
Before Instruction
PC = address (HERE)
After Instruction
If Negative = 0;
PC = address (Jump)
If Negative = 1;
PC = address (HERE + 2)
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BNOV Branch if Not Overflow
Syntax: BNOV n
Operands: -128 n 127
Operation: if Overflow bit is ‘0’,
(PC) + 2 + 2n PC
Status Affected: None
Encoding: 1110 0101 nnnn nnnn
Description: If the Overflow bit is ‘0’, then the
program will branch.
The 2’s complement number ‘2n’ is
added to the PC. Since the PC will have
incremented to fetch the next
instruction, the new address will be
PC + 2 + 2n. This instruction is then a
two-cycle instruction.
Words: 1
Cycles: 1(2)
Q Cycle Activity:
If Jump:
Q1 Q2 Q3 Q4
Decode Read literal
‘n’
Process
Data
Write to
PC
No
operation
No
operation
No
operation
No
operation
If No Jump:
Q1 Q2 Q3 Q4
Decode Read literal
‘n’
Process
Data
No
operation
Example: HERE BNOV Jump
Before Instruction
PC = address (HERE)
After Instruction
If Overflow = 0;
PC = address (Jump)
If Overflow = 1;
PC = address (HERE + 2)
BNZ Branch if Not Zero
Syntax: BNZ n
Operands: -128 n 127
Operation: if Zero bit is ‘0’,
(PC) + 2 + 2n PC
Status Affected: None
Encoding: 1110 0001 nnnn nnnn
Description: If the Zero bit is ‘0’, then the program
will branch.
The 2’s complement number ‘2n’ is
added to the PC. Since the PC will have
incremented to fetch the next
instruction, the new address will be
PC + 2 + 2n. This instruction is then a
two-cycle instruction.
Words: 1
Cycles: 1(2)
Q Cycle Activity:
If Jump:
Q1 Q2 Q3 Q4
Decode Read literal
‘n’
Process
Data
Write to
PC
No
operation
No
operation
No
operation
No
operation
If No Jump:
Q1 Q2 Q3 Q4
Decode Read literal
‘n’
Process
Data
No
operation
Example: HERE BNZ Jump
Before Instruction
PC = address (HERE)
After Instruction
If Zero = 0;
PC = address
(Jump)
If Zero = 1;
PC = address
(HERE + 2)
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BRA Un conditiona l B r a nc h
Syntax: BRA n
Operands: -1024 n 1023
Operation: (PC) + 2 + 2n PC
Status Affected: None
Encoding: 1101 0nnn nnnn nnnn
Description: Add the 2’s complement number ‘2n’ to
the PC. Since the PC will have
incremented to fetch the next
instruction, the new address will be
PC + 2 + 2n. This instruction is a
two-cycle instruction.
Words: 1
Cycles: 2
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read literal
‘n’
Process
Data
Write to
PC
No
operation
No
operation
No
operation
No
operation
Example: HERE BRA Jump
Before Instruction
PC = address (HERE)
After Instruction
PC = address (Jump)
BSF Bit Set f
Syntax: BSF f, b {,a}
Operands: 0 f 255
0 b 7
a [0,1]
Operation: 1 f<b>
Status Affected: None
Encoding: 1000 bbba ffff ffff
Description: Bit ‘b’ in register ‘f’ is set.
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank.
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f 95 (5Fh). See
Section 29.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Index e d
Literal Offset Mode” for details.
Words: 1
Cycles: 1
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read
register ‘f’
Process
Data
Write
register ‘f’
Example: BSF FLAG_REG, 7, 1
Before Instruction
FLAG_REG = 0Ah
After Instruction
FLAG_REG = 8Ah
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BTFSC Bit Tes t File, Sk ip if Clear
Syntax: BTFSC f, b {,a}
Operands: 0 f 255
0 b 7
a [0,1]
Operation: skip if (f<b>) = 0
Status Affected: None
Encoding: 1011 bbba ffff ffff
Description: If bit ‘b’ in register ‘f’ is ‘0’, then the next
instruction is skipped. If bit ‘b’ is ‘0’, then
the next instruction fetched during the
current instruction execution is discarded
and a NOP is executed instead, making
this a two-cycle instruction.
If ‘a’ is ‘0’, the Access Bank is selected. If
‘a’ is ‘1’, the BSR is used to select the
GPR bank.
If ‘a’ is ‘0’ and the extended instruction set
is enabled, this instruction operates in
Indexed Literal Offset Addressing mode
whenever f 95 (5Fh). See
Section 29.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
Words: 1
Cycles: 1(2)
Note: 3 cycles if skip and followed
by a 2-word instruction.
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read
register ‘f’
Process
Data
No
operation
If skip:
Q1 Q2 Q3 Q4
No
operation
No
operation
No
operation
No
operation
If skip and followed by 2-word instruction:
Q1 Q2 Q3 Q4
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
Example: HERE
FALSE
TRUE
BTFSC
:
:
FLAG, 1, 0
Before Instruction
PC = address (HERE)
After Instruction
If FLAG<1> = 0;
PC = address (TRUE)
If FLAG<1> = 1;
PC = address (FALSE)
BTFSS Bit Test Fi le , S k ip if Se t
Syntax: BTFSS f, b {,a}
Operands: 0 f 255
0 b < 7
a [0,1]
Operation: skip if (f<b>) = 1
Status Affected: None
Encoding: 1010 bbba ffff ffff
Description: If bit ‘b’ in register ‘f’ is ‘1’, then the next
instruction is skipped. If bit ‘b’ is ‘1’, then
the next instruction fetched during the
current instruction execution is discarded
and a NOP is executed instead, making
this a two-cycle instruction.
If ‘a’ is ‘0’, the Access Bank is selected. If
‘a’ is ‘1’, the BSR is used to select the
GPR bank.
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates in
Indexed Literal Offset Addressing mode
whenever f 95 (5Fh). See
Section 29.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Index e d
Literal Offset Mode” for details.
Words: 1
Cycles: 1(2)
Note: 3 cycles if skip and followed
by a 2-word instruction.
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read
register ‘f’
Process
Data
No
operation
If skip:
Q1 Q2 Q3 Q4
No
operation
No
operation
No
operation
No
operation
If skip and followed by 2-word instruction:
Q1 Q2 Q3 Q4
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
Example: HERE
FALSE
TRUE
BTFSS
:
:
FLAG, 1, 0
Before Instruction
PC = address (HERE)
After Instruction
If FLAG<1> = 0;
PC = address (FALSE)
If FLAG<1> = 1;
PC = address
(TRUE)
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BTG Bit Toggle f
Syntax: BTG f, b {,a}
Operands: 0 f 255
0 b < 7
a [0,1]
Operation: (f<b>) f<b>
Status Affected: None
Encoding: 0111 bbba ffff ffff
Description: Bit ‘b’ in data memory location, ‘f’, is
inverted.
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank.
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f 95 (5Fh). See
Section 29.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Liter a l Offset Mode” for details.
Words: 1
Cycles: 1
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read
register ‘f’
Process
Data
Write
register ‘f’
Example: BTG PORTC, 4, 0
Before Instruction:
PORTC = 0111 0101 [75h]
After Instruction:
PORTC = 0110 0101 [65h]
BOV B r a nch if O v e r f l ow
Syntax: BOV n
Operands: -128 n 127
Operation: if Overflow bit is ‘1’,
(PC) + 2 + 2n PC
Status Affected: None
Encoding: 1110 0100 nnnn nnnn
Description: If the Overflow bit is ‘1’, then the
program will branch.
The 2’s complement number ‘2n’ is
added to the PC. Since the PC will have
incremented to fetch the next
instruction, the new address will be
PC + 2 + 2n. This instruction is then a
two-cycle instruction.
Words: 1
Cycles: 1(2)
Q Cycle Activity:
If Jump:
Q1 Q2 Q3 Q4
Decode Read literal
‘n’
Process
Data
Write to PC
No
operation
No
operation
No
operation
No
operation
If No Jump:
Q1 Q2 Q3 Q4
Decode Read literal
‘n’
Process
Data
No
operation
Example: HERE BOV Jump
Before Instruction
PC = address (HERE)
After Instruction
If Overflow = 1;
PC = address (Jump)
If Overflow = 0;
PC = address (HERE + 2)
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BZ Branch if Zero
Syntax: BZ n
Operands: -128 n 127
Operation: if Zero bit is ‘1’,
(PC) + 2 + 2n PC
Status Affected: None
Encoding: 1110 0000 nnnn nnnn
Description: If the Zero bit is ‘1’, then the program
will branch.
The 2’s complement number ‘2n’ is
added to the PC. Since the PC will have
incremented to fetch the next
instruction, the new address will be
PC + 2 + 2n. This instruction is then a
two-cycle instruction.
Words: 1
Cycles: 1(2)
Q Cycle Activity:
If Jump:
Q1 Q2 Q3 Q4
Decode Read literal
‘n’
Process
Data
Write to
PC
No
operation
No
operation
No
operation
No
operation
If No Jump:
Q1 Q2 Q3 Q4
Decode Read literal
‘n’
Process
Data
No
operation
Example: HERE BZ Jump
Before Instruction
PC = address (HERE)
After Instruction
If Zero = 1;
PC = address (Jump)
If Zero = 0;
PC = address (HERE + 2)
CALL Subroutine Call
Syntax: CALL k {,s}
Operands: 0 k 1048575
s [0,1]
Operation: (PC) + 4 TOS,
k PC<20:1>;
if s = 1
(W) WS,
(STATUS) STATUSS,
(BSR) BSRS
Status Affected: None
Encoding:
1st word (k<7:0>)
2nd word(k<19:8>)
1110
1111 110s
k19kkk k7kkk
kkkk kkkk0
kkkk8
Description: Subroutine call of entire 2-Mbyte
memory range. First, return address
(PC+ 4) is pushed onto the return stack.
If ‘s’ = 1, the W, STATUS and BSR
registers are also pushed into their
respective shadow registers, WS,
STATUSS and BSRS. If ‘s’ = 0, no
update occurs. Then, the 20-bit value ‘k’
is loaded into PC<20:1>. CALL is a
two-cycle instruction.
Words: 2
Cycles: 2
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read literal
‘k’<7:0>,
Push PC to
stack
Read literal
’k’<19:8>,
Write to PC
No
operation
No
operation
No
operation
No
operation
Example: HERE CALL THERE,1
Before Instruction
PC = address (HERE)
After Instruction
PC = address (THERE)
TOS = address (HERE + 4)
WS = W
BSRS = BSR
STATUSS = STATUS
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CLRF Clear f
Syntax: CLRF f {,a}
Operands: 0 f 255
a [0,1]
Operation: 000h f,
1 Z
Status Affected: Z
Encoding: 0110 101a ffff ffff
Description: Clears the contents of the specified
register.
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank.
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f 95 (5Fh). See
Section 29.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
Words: 1
Cycles: 1
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read
register ‘f’
Process
Data
Write
register ‘f’
Example: CLRF FLAG_REG,1
Before Instruction
FLAG_REG = 5Ah
After Instruction
FLAG_REG = 00h
CLRWDT Clear Watchdog Timer
Syntax: CLRWDT
Operands: None
Operation: 000h WDT,
000h WDT postscaler,
1 TO,
1 PD
Status Affected: TO, PD
Encoding: 0000 0000 0000 0100
Description: CLRWDT instruction resets the
Watchdog Timer. It also resets the post-
scaler of the WDT. Status bits, TO and
PD, are set.
Words: 1
Cycles: 1
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode No
operation
Process
Data
No
operation
Example: CLRWDT
Before Instruction
WDT Counter = ?
After Instruction
WDT Counter = 00h
WDT Postscaler = 0
TO =1
PD =1
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COMF Complement f
Syntax: COMF f {,d {,a}}
Operands: 0 f 255
d [0,1]
a [0,1]
Operation: f dest
Status Affected: N, Z
Encoding: 0001 11da ffff ffff
Description: The contents of register ‘f’ are
complemented. If ‘d’ is ‘0’, the result is
stored in W. If ‘d’ is ‘1’, the result is
stored back in register ‘f’.
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank.
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f 95 (5Fh). See
Section 29.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
Words: 1
Cycles: 1
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read
register ‘f’
Process
Data
Write to
destination
Example: COMF REG, 0, 0
Before Instruction
REG = 13h
After Instruction
REG = 13h
W=ECh
CPFSEQ Compare f with W, Skip if f = W
Syntax: CPFSEQ f {,a}
Operands: 0 f 255
a [0,1]
Operation: (f) – (W),
skip if (f) = (W)
(unsigned comparison)
Status Affected: None
Encoding: 0110 001a ffff ffff
Description: Compares the contents of data memory
location ‘f’ to the contents of W by
performing an unsigned subtraction.
If ‘f’ = W, then the fetched instruction is
discarded and a NOP is executed
instead, making this a two-cycle
instruction.
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank.
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f 95 (5Fh). See
Section 29.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Index e d
Literal Offset Mode” for details.
Words: 1
Cycles: 1(2)
Note: 3 cycles if skip and followed
by a 2-word instruction.
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read
register ‘f’
Process
Data
No
operation
If skip:
Q1 Q2 Q3 Q4
No
operation
No
operation
No
operation
No
operation
If skip and followed by 2-word instruction:
Q1 Q2 Q3 Q4
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
Example: HERE CPFSEQ REG, 0
NEQUAL :
EQUAL :
Before Instruction
PC Address = HERE
W=?
REG = ?
After Instruction
If REG = W;
PC = Address (EQUAL)
If REG W;
PC = Address (NEQUAL)
2011 Microchip Technology Inc. DS39960C-page 449
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CPFSGT Compare f with W, Skip if f > W
Syntax: CPFSGT f {,a}
Operands: 0 f 255
a [0,1]
Operation: (f) –W),
skip if (f) > (W)
(unsigned comparison)
Status Affected: None
Encoding: 0110 010a ffff ffff
Description: Compares the contents of data memory
location ‘f’ to the contents of the W by
performing an unsigned subtraction.
If the contents of ‘f’ are greater than the
contents of WREG, then the fetched
instruction is discarded and a NOP is
executed instead, making this a
two-cycle instruction.
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank.
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f 95 (5Fh). See
Section 29.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
Words: 1
Cycles: 1(2)
Note: 3 cycles if skip and followed
by a 2-word instruction.
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read
register ‘f’
Process
Data
No
operation
If skip:
Q1 Q2 Q3 Q4
No
operation
No
operation
No
operation
No
operation
If skip and followed by 2-word instruction:
Q1 Q2 Q3 Q4
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
Example: HERE CPFSGT REG, 0
NGREATER :
GREATER :
Before Instruction
PC = Address (HERE)
W= ?
After Instruction
If REG W;
PC = Address (GREATER)
If REG W;
PC = Address (NGREATER)
CPFSLT Compare f with W, Skip if f < W
Syntax: CPFSLT f {,a}
Operands: 0 f 255
a [0,1]
Operation: (f) –W),
skip if (f) < (W)
(unsigned comparison)
Status Affected: None
Encoding: 0110 000a ffff ffff
Description: Compares the contents of data memory
location ‘f’ to the contents of W by
performing an unsigned subtraction.
If the contents of ‘f’ are less than the
contents of W, then the fetched
instruction is discarded and a NOP is
executed instead, making this a
two-cycle instruction.
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank.
Words: 1
Cycles: 1(2)
Note: 3 cycles if skip and followed
by a 2-word instruction.
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read
register ‘f’
Process
Data
No
operation
If skip:
Q1 Q2 Q3 Q4
No
operation
No
operation
No
operation
No
operation
If skip and followed by 2-word instruction:
Q1 Q2 Q3 Q4
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
Example: HERE CPFSLT REG, 1
NLESS :
LESS :
Before Instruction
PC = Address (HERE)
W= ?
After Instruction
If REG < W;
PC = Address (LESS)
If REG W;
PC = Address (NLESS)
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DAW Decimal Adjust W Register
Syntax: DAW
Operands: None
Operation: If [W<3:0> > 9] or [DC = 1], then
(W<3:0>) + 6 W<3:0>;
else
(W<3:0>) W<3:0>
If [W<7:4> > 9] or [C = 1], then
(W<7:4>) + 6 W<7:4>;
C =1;
else
(W<7:4>) W<7:4>
Status Affected: C
Encoding: 0000 0000 0000 0111
Description: DAW adjusts the 8-bit value in W,
resulting from the earlier addition of two
variables (each in packed BCD format)
and produces a correct packed BCD
result.
Words: 1
Cycles: 1
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read
register W
Process
Data
Write
W
Example 1: DAW
Before Instruction
W=A5h
C=
0
DC = 0
After Instruction
W = 05h
C=
1
DC = 0
Example 2:
Before Instruction
W=CEh
C=
0
DC = 0
After Instruction
W = 34h
C=
1
DC = 0
DECF Decremen t f
Syntax: DECF f {,d {,a}}
Operands: 0 f 255
d [0,1]
a [0,1]
Operation: (f) – 1 dest
Status Affected: C, DC, N, OV, Z
Encoding: 0000 01da ffff ffff
Description: Decrement register, ‘f’. If ‘d’ is ‘0’, the
result is stored in W. If ‘d’ is ‘1’, the
result is stored back in register ‘f’.
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank.
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f 95 (5Fh). See
Section 29.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Index e d
Literal Offset Mode” for details.
Words: 1
Cycles: 1
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read
register ‘f’
Process
Data
Write to
destination
Example: DECF CNT, 1, 0
Before Instruction
CNT = 01h
Z=
0
After Instruction
CNT = 00h
Z=
1
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DECFSZ Decrement f, Skip if 0
Syntax: DECFSZ f {,d {,a}}
Operands: 0 f 255
d [0,1]
a [0,1]
Operation: (f) – 1 dest,
skip if result = 0
Status Affected: None
Encoding: 0010 11da ffff ffff
Description: The contents of register ‘f’ are
decremented. If ‘d’ is ‘0’, the result is
placed in W. If ‘d’ is ‘1’, the result is
placed back in register ‘f’.
If the result is ‘0’, the next instruction
which is already fetched is discarded
and a NOP is executed instead, making
it a two-cycle instruction.
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank.
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f 95 (5Fh). See
Section 29.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
Words: 1
Cycles: 1(2)
Note: 3 cycles if skip and followed
by a 2-word instruction.
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read
register ‘f’
Process
Data
Write to
destination
If skip:
Q1 Q2 Q3 Q4
No
operation
No
operation
No
operation
No
operation
If skip and followed by 2-word instruction:
Q1 Q2 Q3 Q4
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
Example: HERE DECFSZ CNT, 1, 1
GOTO LOOP
CONTINUE
Before Instruction
PC = Address (HERE)
After Instruction
CNT = CNT – 1
If CNT = 0;
PC = Address (CONTINUE)
If CNT 0;
PC = Address (HERE + 2)
DCFSNZ Decrement f, Skip if Not 0
Syntax: DCFSNZ f {,d {,a}}
Operands: 0 f 255
d [0,1]
a [0,1]
Operation: (f) – 1 dest,
skip if result 0
Status Affected: None
Encoding: 0100 11da ffff ffff
Description: The contents of register ‘f’ are
decremented. If ‘d’ is ‘0’, the result is
placed in W. If ‘d’ is ‘1’, the result is
placed back in register ‘f’.
If the result is not ‘0’, the next
instruction which is already fetched is
discarded and a NOP is executed
instead, making it a two-cycle
instruction.
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank.
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f 95 (5Fh). See
Section 29.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Index e d
Literal Offset Mode” for details.
Words: 1
Cycles: 1(2)
Note: 3 cycles if skip and followed
by a 2-word instruction.
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read
register ‘f’
Process
Data
Write to
destination
If skip:
Q1 Q2 Q3 Q4
No
operation
No
operation
No
operation
No
operation
If skip and followed by 2-word instruction:
Q1 Q2 Q3 Q4
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
Example: HERE DCFSNZ TEMP, 1, 0
ZERO :
NZERO :
Before Instruction
TEMP = ?
After Instruction
TEMP = TEMP – 1,
If TEMP = 0;
PC = Address (ZERO)
If TEMP 0;
PC = Address (NZERO)
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GOTO Unconditional Br a nch
Syntax: GOTO k
Operands: 0 k 1048575
Operation: k PC<20:1>
Status Affected: None
Encoding:
1st word (k<7:0>)
2nd word(k<19:8>)
1110
1111 1111
k19kkk k7kkk
kkkk kkkk0
kkkk8
Description: GOTO allows an unconditional branch
anywhere within entire 2-Mbyte memory
range. The 20-bit value ‘k’ is loaded into
PC<20:1>. GOTO is always a two-cycle
instruction.
Words: 2
Cycles: 2
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read literal
‘k’<7:0>,
No
operation
Read literal
‘k’<19:8>,
Write to PC
No
operation
No
operation
No
operation
No
operation
Example: GOTO THERE
After Instruction
PC = Address (THERE)
INCF Increment f
Syntax: INCF f {,d {,a}}
Operands: 0 f 255
d [0,1]
a [0,1]
Operation: (f) + 1 dest
Status Affected: C, DC, N, OV, Z
Encoding: 0010 10da ffff ffff
Description: The contents of register ‘f’ are
incremented. If ‘d’ is ‘0’, the result is
placed in W. If ‘d’ is ‘1’, the result is
placed back in register ‘f’.
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank.
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f 95 (5Fh). See
Section 29.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Index e d
Literal Offset Mode” for details.
Words: 1
Cycles: 1
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read
register ‘f’
Process
Data
Write to
destination
Example: INCF CNT, 1, 0
Before Instruction
CNT = FFh
Z=
0
C=?
DC = ?
After Instruction
CNT = 00h
Z=1
C=1
DC = 1
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INCFSZ Increment f, Skip if 0
Syntax: INCFSZ f {,d {,a}}
Operands: 0 f 255
d [0,1]
a [0,1]
Operation: (f) + 1 dest,
skip if result = 0
Status Affected: None
Encoding: 0011 11da ffff ffff
Description: The contents of register ‘f’ are
incremented. If ‘d’ is ‘0’, the result is
placed in W. If ‘d’ is ‘1’, the result is
placed back in register ‘f’.
If the result is ‘0’, the next instruction
which is already fetched is discarded
and a NOP is executed instead, making
it a two-cycle instruction.
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank.
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f 95 (5Fh). See
Section 29.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
Words: 1
Cycles: 1(2)
Note: 3 cycles if skip and followed
by a 2-word instruction.
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read
register ‘f’
Process
Data
Write to
destination
If skip:
Q1 Q2 Q3 Q4
No
operation
No
operation
No
operation
No
operation
If skip and followed by 2-word instruction:
Q1 Q2 Q3 Q4
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
Example: HERE INCFSZ CNT, 1, 0
NZERO :
ZERO :
Before Instruction
PC = Address (HERE)
After Instruction
CNT = CNT + 1
If CNT = 0;
PC = Address (ZERO)
If CNT 0;
PC = Address (NZERO)
INFSNZ Increment f, Skip if Not 0
Syntax: INFSNZ f {,d {,a}}
Operands: 0 f 255
d [0,1]
a [0,1]
Operation: (f) + 1 dest,
skip if result 0
Status Affected: None
Encoding: 0100 10da ffff ffff
Description: The contents of register ‘f’ are
incremented. If ‘d’ is ‘0’, the result is
placed in W. If ‘d’ is ‘1’, the result is
placed back in register ‘f’.
If the result is not ‘0’, the next
instruction which is already fetched is
discarded and a NOP is executed
instead, making it a two-cycle
instruction.
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank.
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f 95 (5Fh). See
Section 29.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Index e d
Literal Offset Mode” for details.
Words: 1
Cycles: 1(2)
Note: 3 cycles if skip and followed
by a 2-word instruction.
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read
register ‘f’
Process
Data
Write to
destination
If skip:
Q1 Q2 Q3 Q4
No
operation
No
operation
No
operation
No
operation
If skip and followed by 2-word instruction:
Q1 Q2 Q3 Q4
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
Example: HERE INFSNZ REG, 1, 0
ZERO
NZERO
Before Instruction
PC = Address (HERE)
After Instruction
REG = REG + 1
If REG 0;
PC = Address (NZERO)
If REG = 0;
PC = Address (ZERO)
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IORLW Inclusive OR Litera l with W
Syntax: IORLW k
Operands: 0 k 255
Operation: (W) .OR. k W
Status Affected: N, Z
Encoding: 0000 1001 kkkk kkkk
Description: The contents of W are ORed with the
eight-bit literal ‘k’. The result is placed
in W.
Words: 1
Cycles: 1
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read
literal ‘k’
Process
Data
Write to
W
Example: IORLW 35h
Before Instruction
W=9Ah
After Instruction
W=BFh
IOR WF Inclusive OR W with f
Syntax: IORWF f {,d {,a}}
Operands: 0 f 255
d [0,1]
a [0,1]
Operation: (W) .OR. (f) dest
Status Affected: N, Z
Encoding: 0001 00da ffff ffff
Description: Inclusive OR W with register ‘f’. If ‘d’ is
‘0’, the result is placed in W. If ‘d’ is ‘1’,
the result is placed back in register ‘f’.
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank.
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f 95 (5Fh). See
Section 29.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Index e d
Literal Offset Mode” for details.
Words: 1
Cycles: 1
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read
register ‘f’
Process
Data
Write to
destination
Example: IORWF RESULT, 0, 1
Before Instruction
RESULT = 13h
W = 91h
After Instruction
RESULT = 13h
W = 93h
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LFS R Load FSR
Syntax: LFSR f, k
Operands: 0 f 2
0 k 4095
Operation: k FSRf
Status Affected: None
Encoding: 1110
1111 1110
0000 00ff
k7kkk k11kkk
kkkk
Description: The 12-bit literal ‘k’ is loaded into the
file select register pointed to by ‘f’.
Words: 2
Cycles: 2
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read literal
‘k’ MSB
Process
Data
Write
literal ‘k’
MSB to
FSRfH
Decode Read literal
‘k’ LSB
Process
Data
Write literal
‘k’ to FSRfL
Example: LFSR 2, 3ABh
After Instruction
FSR2H = 03h
FSR2L = ABh
MOVF Move f
Syntax: MOVF f {,d {,a}}
Operands: 0 f 255
d [0,1]
a [0,1]
Operation: f dest
Status Affected: N, Z
Encoding: 0101 00da ffff ffff
Description: The contents of register ‘f’ are moved to
a destination dependent upon the
status of ‘d’. If ‘d’ is ‘0’, the result is
placed in W. If ‘d’ is ‘1’, the result is
placed back in register ‘f’. Location ‘f’
can be anywhere in the
256-byte bank.
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank.
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f 95 (5Fh). See
Section 29.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Index e d
Literal Offset Mode” for details.
Words: 1
Cycles: 1
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read
register ‘f’
Process
Data
Write
W
Example: MOVF REG, 0, 0
Before Instruction
REG = 22h
W=FFh
After Instruction
REG = 22h
W = 22h
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MOVFF Move f to f
Syntax: MOVFF fs,fd
Operands: 0 fs 4095
0 fd 4095
Operation: (fs) fd
Status Affected: None
Encoding:
1st word (source)
2nd word (destin.)
1100
1111 ffff
ffff ffff
ffff ffffs
ffffd
Description: The contents of source register, ‘fs’, are
moved to destination register ‘fd’.
Location of source ‘fs’ can be anywhere
in the 4096-byte data space (000h to
FFFh) and location of destination ‘fd’
can also be anywhere from 000h to
FFFh.
Either source or destination can be W
(a useful special situation).
MOVFF is particularly useful for
transferring a data memory location to a
peripheral register (such as the transmit
buffer or an I/O port).
The MOVFF instruction cannot use the
PCL, TOSU, TOSH or TOSL as the
destination register
Words: 2
Cycles: 2
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read
register ‘f’
(src)
Process
Data
No
operation
Decode No
operation
No dummy
read
No
operation
Write
register ‘f’
(dest)
Example: MOVFF REG1, REG2
Before Instruction
REG1 = 33h
REG2 = 11h
After Instruction
REG1 = 33h
REG2 = 33h
MOVLB Move Literal to Low Nibble in BSR
Syntax: MOVLW k
Operands: 0 k 255
Operation: k BSR
Status Affected: None
Encoding: 0000 0001 kkkk kkkk
Description: The eight-bit literal ‘k’ is loaded into the
Bank Select Register (BSR). The value
of BSR<7:4> always remains ‘0’
regardless of the value of k7:k4.
Words: 1
Cycles: 1
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read
literal ‘k’
Process
Data
Write literal
‘k’ to BSR
Example: MOVLB 5
Before Instruction
BSR Register = 02h
After Instruction
BSR Register = 05h
2011 Microchip Technology Inc. DS39960C-page 457
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MOVLW M ov e Lite ral to W
Syntax: MOVLW k
Operands: 0 k 255
Operation: k W
Status Affected: None
Encoding: 0000 1110 kkkk kkkk
Description: The eight-bit literal ‘k’ is loaded into W.
Words: 1
Cycles: 1
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read
literal ‘k’
Process
Data
Write to
W
Example: MOVLW 5Ah
After Instruction
W=5Ah
MOVWF Move W to f
Syntax: MOVWF f {,a}
Operands: 0 f 255
a [0,1]
Operation: (W) f
Status Affected: None
Encoding: 0110 111a ffff ffff
Description: Move data from W to register ‘f’.
Location ‘f’ can be anywhere in the
256-byte bank.
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank.
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f 95 (5Fh). See
Section 29.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Index ed
Literal Offset Mod e” for details.
Words: 1
Cycles: 1
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read
register ‘f’
Process
Data
Write
register ‘f’
Example: MOVWF REG, 0
Before Instruction
W=4Fh
REG = FFh
After Instruction
W=4Fh
REG = 4Fh
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MULLW Multiply Literal with W
Syntax: MULLW k
Operands: 0 k 255
Operation: (W) x k PRODH:PRODL
Status Affected: None
Encoding: 0000 1101 kkkk kkkk
Description: An unsigned multiplication is carried
out between the contents of W and the
8-bit literal ‘k’. The 16-bit result is
placed in the PRODH:PRODL register
pair. PRODH contains the high byte.
W is unchanged.
None of the Status flags are affected.
Note that neither Overflow nor Carry is
possible in this operation. A Zero result
is possible but not detected.
Words: 1
Cycles: 1
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read
literal ‘k’
Process
Data
Write
registers
PRODH:
PRODL
Example: MULLW 0C4h
Before Instruction
W=E2h
PRODH = ?
PRODL = ?
After Instruction
W=E2h
PRODH = ADh
PRODL = 08h
MULWF Multiply W w ith f
Syntax: MULWF f {,a}
Operands: 0 f 255
a [0,1]
Operation: (W) x (f) PRODH:PRODL
Status Affected: None
Encoding: 0000 001a ffff ffff
Description: An unsigned multiplication is carried out
between the contents of W and the
register file location ‘f’. The 16-bit result is
stored in the PRODH:PRODL register
pair. PRODH contains the high byte. Both
W and ‘f’ are unchanged.
None of the Status flags are affected.
Note that neither Overflow nor Carry is
possible in this operation. A Zero result is
possible but not detected.
If ‘a’ is ‘0’, the Access Bank is selected. If
‘a’ is ‘1’, the BSR is used to select the
GPR bank.
If ‘a’ is ‘0’ and the extended instruction set
is enabled, this instruction operates in
Indexed Literal Offset Addressing mode
whenever f 95 (5Fh). See
Section 29.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Index ed
Literal Offset Mod e” for details.
Words: 1
Cycles: 1
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read
register ‘f’
Process
Data
Write
registers
PRODH:
PRODL
Example: MULWF REG, 1
Before Instruction
W=C4h
REG = B5h
PRODH = ?
PRODL = ?
After Instruction
W=C4h
REG = B5h
PRODH = 8Ah
PRODL = 94h
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NEGF Negate f
Syntax: NEGF f {,a}
Operands: 0 f 255
a [0,1]
Operation: (f) + 1 f
Status Affected: N, OV, C, DC, Z
Encoding: 0110 110a ffff ffff
Description: Location ‘f’ is negated using two’s
complement. The result is placed in the
data memory location ‘f’.
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank.
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f 95 (5Fh). See
Section 29.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Liter a l Offset Mode” for details.
Words: 1
Cycles: 1
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read
register ‘f’
Process
Data
Write
register ‘f’
Example: NEGF REG, 1
Before Instruction
REG = 0011 1010 [3Ah]
After Instruction
REG = 1100 0110 [C6h]
NOP No Operation
Syntax: NOP
Operands: None
Operation: No operation
Status Affected: None
Encoding: 0000
1111 0000
xxxx 0000
xxxx 0000
xxxx
Description: No operation.
Words: 1
Cycles: 1
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode No
operation
No
operation
No
operation
Example:
None.
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POP Pop Top of Return Stack
Syntax: POP
Operands: None
Operation: (TOS) bit bucket
Status Affected: None
Encoding: 0000 0000 0000 0110
Description: The TOS value is pulled off the return
stack and is discarded. The TOS value
then becomes the previous value that
was pushed onto the return stack.
This instruction is provided to enable
the user to properly manage the return
stack to incorporate a software stack.
Words: 1
Cycles: 1
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode No
operation
POP TOS
value
No
operation
Example: POP
GOTO NEW
Before Instruction
TOS = 0031A2h
Stack (1 level down) = 014332h
After Instruction
TOS = 014332h
PC = NEW
PUSH Push Top of Return Stack
Syntax: PUSH
Operands: None
Operation: (PC + 2) TOS
Status Affected: None
Encoding: 0000 0000 0000 0101
Description: The PC + 2 is pushed onto the top of
the return stack. The previous TOS
value is pushed down on the stack.
This instruction allows implementing a
software stack by modifying TOS and
then pushing it onto the return stack.
Words: 1
Cycles: 1
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode PUSH
PC + 2 onto
return stack
No
operation
No
operation
Example: PUSH
Before Instruction
TOS = 345Ah
PC = 0124h
After Instruction
PC = 0126h
TOS = 0126h
Stack (1 level down) = 345Ah
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RCALL Relative Call
Syntax: RCALL n
Operands: -1024 n 1023
Operation: (PC) + 2 TOS,
(PC) + 2 + 2n PC
Status Affected: None
Encoding: 1101 1nnn nnnn nnnn
Description: Subroutine call with a jump up to 1K
from the current location. First, return
address (PC + 2) is pushed onto the
stack. Then, add the 2’s complement
number ‘2n’ to the PC. Since the PC will
have incremented to fetch the next
instruction, the new address will be
PC + 2 + 2n. This instruction is a
two-cycle instruction.
Words: 1
Cycles: 2
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read literal
‘n’
PUSH PC
to stack
Process
Data
Write to PC
No
operation
No
operation
No
operation
No
operation
Example: HERE RCALL Jump
Before Instruction
PC = Address (HERE)
After Instruction
PC = Address (Jump)
TOS = Address (HERE + 2)
RESET Reset
Syntax: RESET
Operands: None
Operation: Reset all registers and flags that are
affected by a MCLR Reset.
Status Affected: All
Encoding: 0000 0000 1111 1111
Description: This instruction provides a way to
execute a MCLR Reset in software.
Words: 1
Cycles: 1
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Start
reset
No
operation
No
operation
Example: RESET
After Instruction
Registers = Reset Value
Flags* = Reset Value
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RETFIE Return from Interrupt
Syntax: RETFIE {s}
Operands: s [0,1]
Operation: (TOS) PC,
1 GIE/GIEH or PEIE/GIEL;
if s = 1,
(WS) W,
(STATUSS) STATUS,
(BSRS) BSR,
PCLATU, PCLATH are unchanged
Status Affected: GIE/GIEH, PEIE/GIEL.
Encoding: 0000 0000 0001 000s
Description: Return from interrupt. Stack is popped
and Top-of-Stack (TOS) is loaded into
the PC. Interrupts are enabled by
setting either the high or low-priority
global interrupt enable bit. If ‘s’ = 1, the
contents of the shadow registers WS,
STATUSS and BSRS are loaded into
their corresponding registers W,
STATUS and BSR. If ‘s’ = 0, no update
of these registers occurs.
Words: 1
Cycles: 2
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode No
operation
No
operation
POP PC
from stack
Set GIEH or
GIEL
No
operation
No
operation
No
operation
No
operation
Example: RETFIE 1
After Interrupt
PC = TOS
W=WS
BSR = BSRS
STATUS = STATUSS
GIE/GIEH, PEIE/GIEL = 1
RETLW Return Literal to W
Syntax: RETLW k
Operands: 0 k 255
Operation: k W,
(TOS) PC,
PCLATU, PCLATH are unchanged
Status Affected: None
Encoding: 0000 1100 kkkk kkkk
Description: W is loaded with the 8-bit literal ‘k’. The
program counter is loaded from the top
of the stack (the return address). The
high address latch (PCLATH) remains
unchanged.
Words: 1
Cycles: 2
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read
literal ‘k’
Process
Data
POP PC
from stack,
write to W
No
operation
No
operation
No
operation
No
operation
Example:
CALL TABLE ; W contains table
; offset value
; W now has
; table value
:
TABLE
ADDWF PCL ; W = offset
RETLW k0 ; Begin table
RETLW k1 ;
:
:RETLW kn ; End of table
Before Instruction
W = 07h
After Instruction
W = value of kn
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RETURN Return from Subroutine
Syntax: RETURN {s}
Operands: s [0,1]
Operation: (TOS) PC;
if s = 1,
(WS) W,
(STATUSS) STATUS,
(BSRS) BSR,
PCLATU, PCLATH are unchanged
Status Affected: None
Encoding: 0000 0000 0001 001s
Description: Return from subroutine. The stack is
popped and the top of the stack (TOS)
is loaded into the program counter. If
‘s’= 1, the contents of the shadow
registers WS, STATUSS and BSRS are
loaded into their corresponding
registers W, STATUS and BSR. If
‘s’ = 0, no update of these registers
occurs.
Words: 1
Cycles: 2
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode No
operation
Process
Data
POP PC
from stack
No
operation
No
operation
No
operation
No
operation
Example: RETURN
After Instruction:
PC = TOS
RLCF Rotate Left f through Carry
Syntax: RLCF f {,d {,a}}
Operands: 0 f 255
d [0,1]
a [0,1]
Operation: (f<n>) dest<n + 1>,
(f<7>) C,
(C) dest<0>
Status Affected: C, N, Z
Encoding: 0011 01da ffff ffff
Description: The contents of register ‘f’ are rotated
one bit to the left through the Carry flag.
If ‘d’ is ‘0’, the result is placed in W. If ‘d’
is ‘1’, the result is stored back in register
‘f’.
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank.
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f 95 (5Fh). See
Section 29.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Index ed
Literal Offset Mod e” for details.
Words: 1
Cycles: 1
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read
register ‘f’
Process
Data
Write to
destination
Example: RLCF REG, 0, 0
Before Instruction
REG = 1110 0110
C=0
After Instruction
REG = 1110 0110
W=1100 1100
C=1
Cregister f
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RLNCF Ro tate Left f (No Carry)
Syntax: RLNCF f {,d {,a}}
Operands: 0 f 255
d [0,1]
a [0,1]
Operation: (f<n>) dest<n + 1>,
(f<7>) dest<0>
Status Affected: N, Z
Encoding: 0100 01da ffff ffff
Description: The contents of register ‘f’ are rotated
one bit to the left. If ‘d’ is ‘0’, the result
is placed in W. If ‘d’ is ‘1’, the result is
stored back in register ‘f’.
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank.
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f 95 (5Fh). See
Section 29.2.3 “Byte-Oriented and
Bit-Oriented Instructi ons in Indexed
Literal Offset Mode” for details.
Words: 1
Cycles: 1
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read
register ‘f’
Process
Data
Write to
destination
Example: RLNCF REG, 1, 0
Before Instruction
REG = 1010 1011
After Instruction
REG = 0101 0111
register f
RRCF Rotate Right f through Carry
Syntax: RRCF f {,d {,a}}
Operands: 0 f 255
d [0,1]
a [0,1]
Operation: (f<n>) dest<n – 1>,
(f<0>) C,
(C) dest<7>
Status Affected: C, N, Z
Encoding: 0011 00da ffff ffff
Description: The contents of register ‘f’ are rotated
one bit to the right through the Carry
flag. If ‘d’ is ‘0’, the result is placed in W.
If ‘d’ is ‘1’, the result is placed back in
register ‘f’.
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank.
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f 95 (5Fh). See
Section 29.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Index e d
Literal Offset Mode” for details.
Words: 1
Cycles: 1
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read
register ‘f’
Process
Data
Write to
destination
Example: RRCF REG, 0, 0
Before Instruction
REG = 1110 0110
C=0
After Instruction
REG = 1110 0110
W=0111 0011
C=0
Cregister f
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RRNCF Rotate Right f (No Carry)
Syntax: RRNCF f {,d {,a}}
Operands: 0 f 255
d [0,1]
a [0,1]
Operation: (f<n>) dest<n – 1>,
(f<0>) dest<7>
Status Affected: N, Z
Encoding: 0100 00da ffff ffff
Description: The contents of register ‘f’ are rotated
one bit to the right. If ‘d’ is ‘0’, the result
is placed in W. If ‘d’ is ‘1’, the result is
placed back in register ‘f’.
If ‘a’ is ‘0’, the Access Bank will be
selected, overriding the BSR value. If ‘a’
is ‘1’, then the bank will be selected as
per the BSR value.
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f 95 (5Fh). See
Section 29.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
Words: 1
Cycles: 1
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read
register ‘f’
Process
Data
Write to
destination
Example 1: RRNCF REG, 1, 0
Before Instruction
REG = 1101 0111
After Instruction
REG = 1110 1011
Example 2: RRNCF REG, 0, 0
Before Instruction
W=?
REG = 1101 0111
After Instruction
W=1110 1011
REG = 1101 0111
register f
SETF Set f
Syntax: SETF f {,a}
Operands: 0 f 255
a [0,1]
Operation: FFh f
Status Affected: None
Encoding: 0110 100a ffff ffff
Description: The contents of the specified register
are set to FFh.
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank.
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f 95 (5Fh). See
Section 29.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Index e d
Literal Offset Mode” for details.
Words: 1
Cycles: 1
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read
register ‘f’
Process
Data
Write
register ‘f’
Example: SETF REG,1
Before Instruction
REG = 5Ah
After Instruction
REG = FFh
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SLEEP Enter Sleep Mod e
Syntax: SLEEP
Operands: None
Operation: 00h WDT,
0 WDT postscaler,
1 TO,
0 PD
Status Affected: TO, PD
Encoding: 0000 0000 0000 0011
Description: The Power-Down status bit (PD) is
cleared. The Time-out status bit (TO)
is set. The Watchdog Timer and its
postscaler are cleared.
The processor is put into Sleep mode
with the oscillator stopped.
Words: 1
Cycles: 1
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode No
operation
Process
Data
Go to
Sleep
Example: SLEEP
Before Instruction
TO =?
PD =?
After Instruction
TO =1 †
PD =0
† If WDT causes wake-up, this bit is cleared.
SUBFWB Subtract f f r om W with Borrow
Syntax: SUBFWB f {,d {,a}}
Operands: 0 f 255
d [0,1]
a [0,1]
Operation: (W) – (f) – (C) dest
Status Affected: N, OV, C, DC, Z
Encoding: 0101 01da ffff ffff
Description: Subtract register ‘f’ and Carry flag
(borrow) from W (2’s complement
method). If ‘d’ is ‘0’, the result is stored in
W. If ‘d’ is ‘1’, the result is stored in
register ‘f’.
If ‘a’ is ‘0’, the Access Bank is selected. If
‘a’ is ‘1’, the BSR is used to select the
GPR bank.
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates in
Indexed Literal Offset Addressing mode
whenever f 95 (5Fh). See
Section 29.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
Words: 1
Cycles: 1
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read
register ‘f’
Process
Data
Write to
destination
Example 1: SUBFWB REG, 1, 0
Before Instruction
REG = 3
W=2
C=1
After Instruction
REG = FF
W=2
C=0
Z=0
N = 1 ; result is negative
Example 2: SUBFWB REG, 0, 0
Before Instruction
REG = 2
W=5
C=1
After Instruction
REG = 2
W=3
C=1
Z=0
N = 0 ; result is positive
Example 3: SUBFWB REG, 1, 0
Before Instruction
REG = 1
W=2
C=0
After Instruction
REG = 0
W=2
C=1
Z = 1 ; result is zero
N=0
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SUBLW Subtract W from Literal
Syntax: SUBLW k
Operands: 0 k 255
Operation: k – (W) W
Status Affected: N, OV, C, DC, Z
Encoding: 0000 1000 kkkk kkkk
Description: W is subtracted from the eight-bit
literal ‘k’. The result is placed in W.
Words: 1
Cycles: 1
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read
literal ‘k’
Process
Data
Write to
W
Example 1: SUBLW 02h
Before Instruction
W = 01h
C=?
After Instruction
W = 01h
C=
1 ; result is positive
Z=
0
N=0
Example 2: SUBLW 02h
Before Instruction
W = 02h
C=?
After Instruction
W = 00h
C=
1 ; result is zero
Z=
1
N=0
Example 3: SUBLW 02h
Before Instruction
W = 03h
C=?
After Instruction
W = FFh ; (2’s complement)
C=
0 ; result is negative
Z=
0
N=1
SUBWF Subtract W from f
Syntax: SUBWF f {,d {,a}}
Operands: 0 f 255
d [0,1]
a [0,1]
Operation: (f) – (W) dest
Status Affected: N, OV, C, DC, Z
Encoding: 0101 11da ffff ffff
Description: Subtract W from register ‘f’ (2’s
complement method). If ‘d’ is ‘0’, the
result is stored in W. If ‘d’ is ‘1’, the result
is stored back in register ‘f’.
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank.
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f 95 (5Fh). See
Section 29.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Liter a l Offset Mode” for details.
Words: 1
Cycles: 1
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read
register ‘f’
Process
Data
Write to
destination
Example 1: SUBWF REG, 1, 0
Before Instruction
REG = 3
W=2
C=?
After Instruction
REG = 1
W=2
C = 1 ; result is positive
Z=0
N=0
Example 2: SUBWF REG, 0, 0
Before Instruction
REG = 2
W=2
C=?
After Instruction
REG = 2
W=0
C = 1 ; result is zero
Z=1
N=0
Example 3: SUBWF REG, 1, 0
Before Instruction
REG = 1
W=2
C=?
After Instruction
REG = FFh ;(2’s complement)
W=2
C = 0 ; result is negative
Z=0
N=1
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SUBWFB Subtract W from f with Borrow
Syntax: SUBWFB f {,d {,a}}
Operands: 0 f 255
d [0,1]
a [0,1]
Operation: (f) – (W) – (C) dest
Status Affected: N, OV, C, DC, Z
Encoding: 0101 10da ffff ffff
Description: Subtract W and the Carry flag (borrow)
from register ‘f’ (2’s complement
method). If ‘d’ is ‘0’, the result is stored
in W. If ‘d’ is ‘1’, the result is stored back
in register ‘f’.
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank.
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f 95 (5Fh). See
Section 29.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
Words: 1
Cycles: 1
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read
register ‘f’
Process
Data
Write to
destination
Example 1: SUBWFB REG, 1, 0
Before Instruction
REG = 19h (0001 1001)
W=0Dh (0000 1101)
C=1
After Instruction
REG = 0Ch (0000 1011)
W=0Dh (0000 1101)
C=1
Z=0
N=0 ; result is positive
Example 2: SUBWFB REG, 0, 0
Before Instruction
REG = 1Bh (0001 1011)
W=1Ah (0001 1010)
C=0
After Instruction
REG = 1Bh (0001 1011)
W = 00h
C=
1
Z=1 ; result is zero
N=
0
Example 3: SUBWFB REG, 1, 0
Before Instruction
REG = 03h (0000 0011)
W=0Eh (0000 1101)
C=1
After Instruction
REG = F5h (1111 0100)
; [2’s comp]
W=0Eh (0000 1101)
C=0
Z=0
N=1 ; result is negative
SW APF Swap f
Syntax: SWAPF f {,d {,a}}
Operands: 0 f 255
d [0,1]
a [0,1]
Operation: (f<3:0>) dest<7:4>,
(f<7:4>) dest<3:0>
Status Affected: None
Encoding: 0011 10da ffff ffff
Description: The upper and lower nibbles of register
‘f’ are exchanged. If ‘d’ is ‘0’, the result
is placed in W. If ‘d’ is ‘1’, the result is
placed in register ‘f’.
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank.
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f 95 (5Fh). See
Section 29.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Index e d
Literal Offset Mode” for details.
Words: 1
Cycles: 1
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read
register ‘f’
Process
Data
Write to
destination
Example: SWAPF REG, 1, 0
Before Instruction
REG = 53h
After Instruction
REG = 35h
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TBLRD Table Read
Syntax: TBLRD ( *; *+; *-; +*)
Operands: None
Operation: if TBLRD *,
(Prog Mem (TBLPTR)) TABLAT;
TBLPTR – No Change
if TBLRD *+,
(Prog Mem (TBLPTR)) TABLAT;
(TBLPTR) + 1 TBLPTR
if TBLRD *-,
(Prog Mem (TBLPTR)) TABLAT;
(TBLPTR) – 1 TBLPTR
if TBLRD +*,
(TBLPTR) + 1 TBLPTR;
(Prog Mem (TBLPTR)) TABLAT
Status Affected: None
Encoding: 0000 0000 0000 10nn
nn=0 *
=1 *+
=2 *-
=3 +*
Description: This instruction is used to read the contents
of Program Memory (P.M.). To address the
program memory, a pointer called Table
Pointer (TBLPTR) is used.
The TBLPTR (a 21-bit pointer) points to
each byte in the program memory. TBLPTR
has a 2-Mbyte address range.
TBLPTR<0> = 0:Least Significant Byte of
Program Memory Word
TBLPTR<0> = 1:Most Significant Byte of
Program Memory Word
The TBLRD instruction can modify the value
of TBLPTR as follows:
• no change
• post-increment
• post-decrement
• pre-increment
Words: 1
Cycles: 2
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode No
operation
No
operation
No
operation
No
operation
No operation
(Read Program
Memory)
No
operation
No operation
(Write
TABLAT)
TBLRD Table Read (Continued)
Example 1: TBLRD *+ ;
Before Instruction
TABLAT = 55h
TBLPTR = 00A356h
MEMORY(00A356h) = 34h
After Instruction
TABLAT = 34h
TBLPTR = 00A357h
Example 2: TBLRD +* ;
Before Instruction
TABLAT = AAh
TBLPTR = 01A357h
MEMORY(01A357h) = 12h
MEMORY(01A358h) = 34h
After Instruction
TABLAT = 34h
TBLPTR = 01A358h
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TBLWT Table Write
Syntax: TBLWT ( *; *+; *-; +*)
Operands: None
Operation: if TBLWT*,
(TABLAT) Holding Register;
TBLPTR – No Change
if TBLWT*+,
(TABLAT) Holding Register;
(TBLPTR) + 1 TBLPTR
if TBLWT*-,
(TABLAT) Holding Register;
(TBLPTR) – 1 TBLPTR
if TBLWT+*,
(TBLPTR) + 1 TBLPTR;
(TABLAT) Holding Register
Status Affected: None
Encoding: 0000 0000 0000 11nn
nn=0 *
=1 *+
=2 *-
=3 +*
Description: This instruction uses the 3 LSBs of
TBLPTR to determine which of the
8 holding registers the TABLAT is written
to. The holding registers are used to
program the contents of Program Memory
(P.M.). (Refer to Section 6.0 “Memory
Organization” for additional details on
programming Flash memory.)
The TBLPTR (a 21-bit pointer) points to
each byte in the program memory.
TBLPTR has a 2-Mbyte address range.
The LSb of the TBLPTR selects which
byte of the program memory location to
access.
TBLPTR[0] = 0:Least Significant Byte
of Program Memory
Word
TBLPTR[0] = 1:Most Significant Byte of
Program Memory
Word
The TBLWT instruction can modify the
value of TBLPTR as follows:
• no change
• post-increment
• post-decrement
• pre-increment
Words: 1
Cycles: 2
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode No
operation
No
operation
No
operation
No
operation
No
operation
(Read
TABLAT)
No
operation
No
operation
(Write to
Holding
Register)
TBLWT Table Write (Continued)
Example 1: TBLWT *+;
Before Instruction
TABLAT = 55h
TBLPTR = 00A356h
HOLDING REGISTER
(00A356h) = FFh
After Instructions (table write completion)
TABLAT = 55h
TBLPTR = 00A357h
HOLDING REGISTER
(00A356h) = 55h
Example 2: TBLWT +*;
Before Instruction
TABLAT = 34h
TBLPTR = 01389Ah
HOLDING REGISTER
(01389Ah) = FFh
HOLDING REGISTER
(01389Bh) = FFh
After Instruction (table write completion)
TABLAT = 34h
TBLPTR = 01389Bh
HOLDING REGISTER
(01389Ah) = FFh
HOLDING REGISTER
(01389Bh) = 34h
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TST FSZ Test f, Skip if 0
Syntax: TSTFSZ f {,a}
Operands: 0 f 255
a [0,1]
Operation: skip if f = 0
Status Affected: None
Encoding: 0110 011a ffff ffff
Description: If ‘f’ = 0, the next instruction fetched
during the current instruction execution
is discarded and a NOP is executed,
making this a two-cycle instruction.
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank.
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f 95 (5Fh). See
Section 29.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
Words: 1
Cycles: 1(2)
Note: 3 cycles if skip and followed
by a 2-word instruction.
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read
register ‘f’
Process
Data
No
operation
If skip:
Q1 Q2 Q3 Q4
No
operation
No
operation
No
operation
No
operation
If skip and followed by 2-word instruction:
Q1 Q2 Q3 Q4
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
Example: HERE TSTFSZ CNT, 1
NZERO :
ZERO :
Before Instruction
PC = Address (HERE)
After Instruction
If CNT = 00h,
PC = Address (ZERO)
If CNT 00h,
PC = Address
(NZERO)
XORLW Exclusive OR Literal with W
Syntax: XORLW k
Operands: 0 k 255
Operation: (W) .XOR. k W
Status Affected: N, Z
Encoding: 0000 1010 kkkk kkkk
Description: The contents of W are XORed with
the 8-bit literal ‘k’. The result is placed
in W.
Words: 1
Cycles: 1
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read
literal ‘k’
Process
Data
Write to
W
Example: XORLW 0AFh
Before Instruction
W=B5h
After Instruction
W=1Ah
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XORWF Exclusive OR W with f
Syntax: XORWF f {,d {,a}}
Operands: 0 f 255
d [0,1]
a [0,1]
Operation: (W) .XOR. (f) dest
Status Affected: N, Z
Encoding: 0001 10da ffff ffff
Description: Exclusive OR the contents of W with
register ‘f’. If ‘d’ is ‘0’, the result is stored
in W. If ‘d’ is ‘1’, the result is stored back
in the register ‘f’.
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank.
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f 95 (5Fh). See
Section 29.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
Words: 1
Cycles: 1
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read
register ‘f’
Process
Data
Write to
destination
Example: XORWF REG, 1, 0
Before Instruction
REG = AFh
W=B5h
After Instruction
REG = 1Ah
W=B5h
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29.2 Extended Instruction Set
In addition to the standard 75 instructions of the PIC18
instruction set, the PIC18F87K22 family of devices also
provides an optional extension to the core CPU func-
tionality. The added features include eight additional
instructions that augment Indirect and Indexed
Addressing operations and the implementation of
Indexed Literal Offset Addressing for many of the
standard PIC18 instructions.
The additional features of the extended instruction set
are enabled by default on unprogrammed devices.
Users must properly set or clear the XINST Configura-
tion bit during programming to enable or disable these
features.
The instructions in the extended set can all be
classified as literal operations, which either manipulate
the File Select Registers, or use them for Indexed
Addressing. Two of the instructions, ADDFSR and
SUBFSR, each have an additional special instantiation
for using FSR2. These versions (ADDULNK and
SUBULNK) allow for automatic return after execution.
The extended instructions are specifically implemented
to optimize re-entrant program code (that is, code that
is recursive or that uses a software stack) written in
high-level languages, particularly C. Among other
things, they allow users working in high-level
languages to perform certain operations on data
structures more efficiently. These include:
• Dynamic allocation and deallocation of software
stack space when entering and leaving
subroutines
• Function Pointer invocation
• Software Stack Pointer manipulation
• Manipulation of variables located in a software
stack
A summary of the instructions in the extended instruc-
tion set is provided in Table 29 -3. Detailed descriptions
are provided in Section 29.2.2 “Extended Instruction
Set”. The opcode field descriptions in Tab l e 29- 1
(page 432) apply to both the standard and extended
PIC18 instruction sets.
29.2.1 EXTENDED INSTRUCTION SYNTAX
Most of the extended instructions use indexed argu-
ments, using one of the File Select Registers and some
offset to specify a source or destination register. When
an argument for an instruction serves as part of
Indexed Addressing, it is enclosed in square brackets
(“[ ]”). This is done to indicate that the argument is used
as an index or offset. The MPASM™ Assembler will
flag an error if it determines that an index or offset value
is not bracketed.
When the extended instruction set is enabled, brackets
are also used to indicate index arguments in
byte-oriented and bit-oriented instructions. This is in
addition to other changes in their syntax. For more
details, see Section 29.2.3.1 “Extended Instruction
Syntax with Standard PIC18 Commands”.
TABLE 29-3: EXTENSIONS TO THE PIC18 INSTRUCTION SET
Note: The instruction set extension and the
Indexed Literal Offset Addressing mode
were designed for optimizing applications
written in C; the user may likely never use
these instructions directly in assembler.
The syntax for these commands is
provided as a reference for users who
may be reviewing code that has been
generated by a compiler.
Note: In the past, square brackets have been
used to denote optional arguments in the
PIC18 and earlier instruction sets. In this
text and going forward, optional
arguments are denoted by braces (“{ }”).
Mnemonic,
Operands Description Cycles 16-Bit Instruction Word Status
Affected
MSb LSb
ADDFSR
ADDULNK
CALLW
MOVSF
MOVSS
PUSHL
SUBFSR
SUBULNK
f, k
k
zs, fd
zs, zd
k
f, k
k
Add Literal to FSR
Add Literal to FSR2 and Return
Call Subroutine using WREG
Move zs (source) to 1st word
fd (destination) 2nd word
Move zs (source) to 1st word
zd (destination) 2nd word
Store Literal at FSR2,
Decrement FSR2
Subtract Literal from FSR
Subtract Literal from FSR2 and
return
1
2
2
2
2
1
1
2
1110
1110
0000
1110
1111
1110
1111
1110
1110
1110
1000
1000
0000
1011
ffff
1011
xxxx
1010
1001
1001
ffkk
11kk
0001
0zzz
ffff
1zzz
xzzz
kkkk
ffkk
11kk
kkkk
kkkk
0100
zzzz
ffff
zzzz
zzzz
kkkk
kkkk
kkkk
None
None
None
None
None
None
None
None
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29.2.2 EXTENDED INSTRUCTION SET
ADDFSR Add Literal to FSR
Syntax: ADDFSR f, k
Operands: 0 k 63
f [ 0, 1, 2 ]
Operation: FSR(f) + k FSR(f)
Status Affected: None
Encoding: 1110 1000 ffkk kkkk
Description: The 6-bit literal ‘k’ is added to the
contents of the FSR specified by ‘f’.
Words: 1
Cycles: 1
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read
literal ‘k’
Process
Data
Write to
FSR
Example: ADDFSR 2, 23h
Before Instruction
FSR2 = 03FFh
After Instruction
FSR2 = 0422h
ADDULNK Add Literal to FSR2 and Return
Syntax: ADDULNK k
Operands: 0 k 63
Operation: FSR2 + k FSR2,
(TOS) PC
Status Affected: None
Encoding: 1110 1000 11kk kkkk
Description: The 6-bit literal ‘k’ is added to the
contents of FSR2. A RETURN is then
executed by loading the PC with the
TOS.
The instruction takes two cycles to
execute; a NOP is performed during
the second cycle.
This may be thought of as a special
case of the ADDFSR instruction,
where f = 3 (binary ‘11’); it operates
only on FSR2.
Words: 1
Cycles: 2
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read
literal ‘k’
Process
Data
Write to
FSR
No
Operation
No
Operation
No
Operation
No
Operation
Example: ADDULNK 23h
Before Instruction
FSR2 = 03FFh
PC = 0100h
After Instruction
FSR2 = 0422h
PC = (TOS)
Note: All PIC18 instructions may take an optional label argument preceding the instruction mnemonic for use in
symbolic addressing. If a label is used, the instruction format then becomes: {label} instruction argument(s).
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CALLW Subroutine Call Using WREG
Syntax: CALLW
Operands: None
Operation: (PC + 2) TOS,
(W) PCL,
(PCLATH) PCH,
(PCLATU) PCU
Status Affected: None
Encoding: 0000 0000 0001 0100
Description First, the return address (PC + 2) is
pushed onto the return stack. Next, the
contents of W are written to PCL; the
existing value is discarded. Then, the
contents of PCLATH and PCLATU are
latched into PCH and PCU,
respectively. The second cycle is
executed as a NOP instruction while the
new next instruction is fetched.
Unlike CALL, there is no option to
update W, STATUS or BSR.
Words: 1
Cycles: 2
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read
WREG
Push PC to
stack
No
operation
No
operation
No
operation
No
operation
No
operation
Example: HERE CALLW
Before Instruction
PC = address (HERE)
PCLATH = 10h
PCLATU = 00h
W = 06h
After Instruction
PC = 001006h
TOS = address (HERE + 2)
PCLATH = 10h
PCLATU = 00h
W = 06h
MOV S F Mo v e Indexed to f
Syntax: MOVSF [zs], fd
Operands: 0 zs 127
0 fd 4095
Operation: ((FSR2) + zs) fd
Status Affected: None
Encoding:
1st word (source)
2nd word (destin.)
1110
1111 1011
ffff 0zzz
ffff zzzzs
ffffd
Description: The contents of the source register are
moved to destination register ‘fd’. The
actual address of the source register is
determined by adding the 7-bit literal
offset ‘zs’, in the first word, to the value
of FSR2. The address of the destination
register is specified by the 12-bit literal
‘fd’ in the second word. Both addresses
can be anywhere in the 4096-byte data
space (000h to FFFh).
The MOVSF instruction cannot use the
PCL, TOSU, TOSH or TOSL as the
destination register.
If the resultant source address points to
an Indirect Addressing register, the
value returned will be 00h.
Words: 2
Cycles: 2
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Determine
source addr
Determine
source addr
Read
source reg
Decode No
operation
No dummy
read
No
operation
Write
register ‘f’
(dest)
Example: MOVSF [05h], REG2
Before Instruction
FSR2 = 80h
Contents
of 85h = 33h
REG2 = 11h
After Instruction
FSR2 = 80h
Contents
of 85h = 33h
REG2 = 33h
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MOVSS Move Indexed to Indexed
Syntax: MOVSS [zs], [zd]
Operands: 0 zs 127
0 zd 127
Operation: ((FSR2) + zs) ((FSR2) + zd)
Status Affected: None
Encoding:
1st word (source)
2nd word (dest.)
1110
1111 1011
xxxx 1zzz
xzzz zzzzs
zzzzd
Description The contents of the source register are
moved to the destination register. The
addresses of the source and destination
registers are determined by adding the
7-bit literal offsets, ‘zs’ or ‘zd’,
respectively, to the value of FSR2. Both
registers can be located anywhere in
the 4096-byte data memory space
(000h to FFFh).
The MOVSS instruction cannot use the
PCL, TOSU, TOSH or TOSL as the
destination register.
If the resultant source address points to
an Indirect Addressing register, the
value returned will be 00h. If the
resultant destination address points to
an Indirect Addressing register, the
instruction will execute as a NOP.
Words: 2
Cycles: 2
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Determine
source addr
Determine
source addr
Read
source reg
Decode Determine
dest addr
Determine
dest addr
Write
to dest reg
Example: MOVSS [05h], [06h]
Before Instruction
FSR2 = 80h
Contents
of 85h = 33h
Contents
of 86h = 11h
After Instruction
FSR2 = 80h
Contents
of 85h = 33h
Contents
of 86h = 33h
PUSHL Store Literal at FSR2, Decrement FSR2
Syntax: PUSHL k
Operands: 0k 255
Operation: k (FSR2),
FSR2 – 1 FSR2
Status Affected: None
Encoding: 1111 1010 kkkk kkkk
Description: The 8-bit literal ‘k’ is written to the data
memory address specified by FSR2.
FSR2 is decremented by 1 after the
operation.
This instruction allows users to push
values onto a software stack.
Words: 1
Cycles: 1
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read ‘k’ Process
data
Write to
destination
Example: PUSHL 08h
Before Instruction
FSR2H:FSR2L = 01ECh
Memory (01ECh) = 00h
After Instruction
FSR2H:FSR2L = 01EBh
Memory (01ECh) = 08h
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SUBFSR Subtract Literal from FSR
Syntax: SUBFSR f, k
Operands: 0 k 63
f [ 0, 1, 2 ]
Operation: FSRf – k FSRf
Status Affected: None
Encoding: 1110 1001 ffkk kkkk
Description: The 6-bit literal ‘k’ is subtracted from
the contents of the FSR specified
by ‘f’.
Words: 1
Cycles: 1
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read
register ‘f’
Process
Data
Write to
destination
Example: SUBFSR 2, 23h
Before Instruction
FSR2 = 03FFh
After Instruction
FSR2 = 03DCh
SUBULNK Su btract Literal f rom FSR2 and Return
Syntax: SUBULNK k
Operands: 0 k 63
Operation: FSR2 – k FSR2,
(TOS) PC
Status Affected: None
Encoding: 1110 1001 11kk kkkk
Description: The 6-bit literal ‘k’ is subtracted from the
contents of the FSR2. A RETURN is then
executed by loading the PC with the
TOS.
The instruction takes two cycles to
execute; a NOP is performed during the
second cycle.
This may be thought of as a special case
of the SUBFSR instruction, where f = 3
(binary ‘11’); it operates only on FSR2.
Words: 1
Cycles: 2
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read
register ‘f’
Process
Data
Write to
destination
No
Operation
No
Operation
No
Operation
No
Operation
Example: SUBULNK 23h
Before Instruction
FSR2 = 03FFh
PC = 0100h
After Instruction
FSR2 = 03DCh
PC = (TOS)
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29.2.3 BYTE-ORIENTED AND
BIT-ORIENTED INSTRUCTIONS IN
INDEXED LITERAL OFFSET MODE
In addition to eight new commands in the extended set,
enabling the extended instruction set also enables
Indexed Literal Offset Addressing (Section 6.6.1
“Indexed Addressing with Literal Offset”). This has
a significant impact on the way that many commands of
the standard PIC18 instruction set are interpreted.
When the extended set is disabled, addresses embed-
ded in opcodes are treated as literal memory locations:
either as a location in the Access Bank (a = 0) or in a
GPR bank designated by the BSR (a = 1). When the
extended instruction set is enabled and a = 0, however,
a file register argument of 5Fh or less is interpreted as
an offset from the pointer value in FSR2 and not as a
literal address. For practical purposes, this means that
all instructions that use the Access RAM bit as an
argument – that is, all byte-oriented and bit-oriented
instructions, or almost half of the core PIC18 instruc-
tions – may behave differently when the extended
instruction set is enabled.
When the content of FSR2 is 00h, the boundaries of the
Access RAM are essentially remapped to their original
values. This may be useful in creating backward
compatible code. If this technique is used, it may be
necessary to save the value of FSR2 and restore it
when moving back and forth between C and assembly
routines in order to preserve the Stack Pointer. Users
must also keep in mind the syntax requirements of the
extended instruction set (see Section 29.2.3.1
“Extended Instruction Syntax with Standard PIC18
Commands”).
Although the Indexed Literal Offset mode can be very
useful for dynamic stack and pointer manipulation, it
can also be very annoying if a simple arithmetic opera-
tion is carried out on the wrong register. Users who are
accustomed to the PIC18 programming must keep in
mind, that when the extended instruction set is
enabled, register addresses of 5Fh or less are used for
Indexed Literal Offset Addressing.
Representative examples of typical byte-oriented and
bit-oriented instructions in the Indexed Literal Offset
mode are provided on the following page to show how
execution is affected. The operand conditions shown in
the examples are applicable to all instructions of these
types.
29.2.3.1 Extended Instruction Syntax with
Standard PIC18 Commands
When the extended instruction set is enabled, the file
register argument ‘f’ in the standard byte-oriented and
bit-oriented commands is replaced with the literal offset
value ‘k’. As already noted, this occurs only when ‘f’ is
less than or equal to 5Fh. When an offset value is used,
it must be indicated by square brackets (“[ ]”). As with
the extended instructions, the use of brackets indicates
to the compiler that the value is to be interpreted as an
index or an offset. Omitting the brackets, or using a
value greater than 5Fh within the brackets, will
generate an error in the MPASM™ Assembler.
If the index argument is properly bracketed for Indexed
Literal Offset Addressing, the Access RAM argument is
never specified; it will automatically be assumed to be
‘0’. This is in contrast to standard operation (extended
instruction set disabled), when ‘a’ is set on the basis of
the target address. Declaring the Access RAM bit in
this mode will also generate an error in the MPASM
Assembler.
The destination argument, ‘d’, functions as before.
In the latest versions of the MPASM Assembler,
language support for the extended instruction set must
be explicitly invoked. This is done with either the
command line option, /y, or the PE directive in the
source listing.
29.2.4 CONSIDERATIONS WHEN
ENABLING THE EXTENDED
INSTRUCTION SET
It is important to note that the extensions to the instruc-
tion set may not be beneficial to all users. In particular,
users who are not writing code that uses a software
stack may not benefit from using the extensions to the
instruction set.
Additionally, the Indexed Literal Offset Addressing
mode may create issues with legacy applications
written to the PIC18 assembler. This is because
instructions in the legacy code may attempt to address
registers in the Access Bank below 5Fh. Since these
addresses are interpreted as literal offsets to FSR2
when the instruction set extension is enabled, the
application may read or write to the wrong data
addresses.
When porting an application to the PIC18F87K22
family, it is very important to consider the type of code.
A large, re-entrant application that is written in C and
would benefit from efficient compilation will do well
when using the instruction set extensions. Legacy
applications that heavily use the Access Bank will most
likely not benefit from using the extended instruction
set.
Note: Enabling the PIC18 instruction set exten-
sion may cause legacy applications to
behave erratically or fail entirely.
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ADDWF ADD W to Indexed
(Indexed Literal Offset mode)
Syntax: ADDWF [k] {,d}
Operands: 0 k 95
d [0,1]
Operation: (W) + ((FSR2) + k) dest
Status Affected: N, OV, C, DC, Z
Encoding: 0010 01d0 kkkk kkkk
Description: The contents of W are added to the
contents of the register indicated by
FSR2, offset by the value ‘k’.
If ‘d’ is ‘0’, the result is stored in W. If ‘d’
is ‘1’, the result is stored back in
register ‘f’.
Words: 1
Cycles: 1
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read ‘k’ Process
Data
Write to
destination
Example: ADDWF [OFST] ,0
Before Instruction
W = 17h
OFST = 2Ch
FSR2 = 0A00h
Contents
of 0A2Ch = 20h
After Instruction
W = 37h
Contents
of 0A2Ch = 20h
BSF Bit Set Indexed
(Indexed Literal Offset mode)
Syntax: BSF [k], b
Operands: 0 f 95
0 b 7
Operation: 1 ((FSR2) + k)<b>
Status Affected: None
Encoding: 1000 bbb0 kkkk kkkk
Description: Bit ‘b’ of the register indicated by FSR2,
offset by the value ‘k’, is set.
Words: 1
Cycles: 1
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read
register ‘f’
Process
Data
Write to
destination
Example: BSF [FLAG_OFST], 7
Before Instruction
FLAG_OFST = 0Ah
FSR2 = 0A00h
Contents
of 0A0Ah = 55h
After Instruction
Contents
of 0A0Ah = D5h
SETF Set Indexed
(Indexed Literal Offset mode)
Syntax: SETF [k]
Operands: 0 k 95
Operation: FFh ((FSR2) + k)
Status Affected: None
Encoding: 0110 1000 kkkk kkkk
Description: The contents of the register indicated by
FSR2, offset by ‘k’, are set to FFh.
Words: 1
Cycles: 1
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read ‘k’ Process
Data
Write
register
Example: SETF [OFST]
Before Instruction
OFST = 2Ch
FSR2 = 0A00h
Contents
of 0A2Ch = 00h
After Instruction
Contents
of 0A2Ch = FFh
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29.2.5 SPECIAL CONSIDERATIONS WITH
MICROCHIP MPLAB® IDE TOOLS
The latest versions of Microchip’s software tools have
been designed to fully support the extended instruction
set for the PIC18F87K22 family. This includes the
MPLAB C18 C Compiler, MPASM assembly language
and MPLAB Integrated Development Environment
(IDE).
When selecting a target device for software
development, MPLAB IDE will automatically set default
Configuration bits for that device. The default setting for
the XINST Configuration bit is ‘0’, disabling the
extended instruction set and Indexed Literal Offset
Addressing. For proper execution of applications
developed to take advantage of the extended
instruction set, XINST must be set during
programming.
To develop software for the extended instruction set,
the user must enable support for the instructions and
the Indexed Addressing mode in their language tool(s).
Depending on the environment being used, this may be
done in several ways:
• A menu option or dialog box within the
environment that allows the user to configure the
language tool and its settings for the project
• A command line option
• A directive in the source code
These options vary between different compilers,
assemblers and development environments. Users are
encouraged to review the documentation accompany-
ing their development systems for the appropriate
information.
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30.0 DEVELOPMENT SUPPORT
The PIC® microcontrollers and dsPIC® digital signal
controllers are supported with a full range of software
and hardware development tools:
• Integrated Development Environment
- MPLAB® IDE Software
• Compilers/Assemblers/Linkers
- MPLAB C Compiler for Various Device
Families
- HI-TECH C for Various Device Families
- MPASMTM Assembler
-MPLINK
TM Object Linker/
MPLIBTM Object Librarian
- MPLAB Assembler/Linker/Librarian for
Various Device Families
• Simulators
- MPLAB SIM Software Simulator
•Emulators
- MPLAB REAL ICE™ In-Circuit Emulator
• In-Circuit Debuggers
- MPLAB ICD 3
- PICkit™ 3 Debug Express
• Device Programmers
- PICkit™ 2 Programmer
- MPLAB PM3 Device Programmer
• Low-Cost Demonstration/Development Boards,
Evaluation Kits, and Starter Kits
30.1 MPLAB Integrated Development
Environment Software
The MPLAB IDE software brings an ease of software
development previously unseen in the 8/16/32-bit
microcontroller market. The MPLAB IDE is a Windows®
operating system-based application that contains:
• A single graphical interface to all debugging tools
- Simulator
- Programmer (sold separately)
- In-Circuit Emulator (sold separately)
- In-Circuit Debugger (sold separately)
• A full-featured editor with color-coded context
• A multiple project manager
• Customizable data windows with direct edit of
contents
• High-level source code debugging
• Mouse over variable inspection
• Drag and drop variables from source to watch
windows
• Extensive on-line help
• Integration of select third party tools, such as
IAR C Compilers
The MPLAB IDE allows you to:
• Edit your source files (either C or assembly)
• One-touch compile or assemble, and download to
emulator and simulator tools (automatically
updates all project information)
• Debug using:
- Source files (C or assembly)
- Mixed C and assembly
- Machine code
MPLAB IDE supports multiple debugging tools in a
single development paradigm, from the cost-effective
simulators, through low-cost in-circuit debuggers, to
full-featured emulators. This eliminates the learning
curve when upgrading to tools with increased flexibility
and power.
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30.2 MPLAB C Compilers for Various
Device Families
The MPLAB C Compiler code development systems
are complete ANSI C compilers for Microchip’s PIC18,
PIC24 and PIC32 families of microcontrollers and the
dsPIC30 and dsPIC33 families of digital signal control-
lers. These compilers provide powerful integration
capabilities, superior code optimization and ease of
use.
For easy source level debugging, the compilers provide
symbol information that is optimized to the MPLAB IDE
debugger.
30.3 HI-TECH C for Various Device
Families
The HI-TECH C Compiler code development systems
are complete ANSI C compilers for Microchip’s PIC
family of microcontrollers and the dsPIC family of digital
signal controllers. These compilers provide powerful
integration capabilities, omniscient code generation
and ease of use.
For easy source level debugging, the compilers provide
symbol information that is optimized to the MPLAB IDE
debugger.
The compilers include a macro assembler, linker, pre-
processor, and one-step driver, and can run on multiple
platforms.
30.4 MPASM Assembler
The MPASM Assembler is a full-featured, universal
macro assembler for PIC10/12/16/18 MCUs.
The MPASM Assembler generates relocatable object
files for the MPLINK Object Linker, Intel® standard HEX
files, MAP files to detail memory usage and symbol
reference, absolute LST files that contain source lines
and generated machine code and COFF files for
debugging.
The MPASM Assembler features include:
• Integration into MPLAB IDE projects
• User-defined macros to streamline
assembly code
• Conditional assembly for multi-purpose
source files
• Directives that allow complete control over the
assembly process
30.5 MPLINK Object Linker/
MPLIB Object Librarian
The MPLINK Object Linker combines relocatable
objects created by the MPASM Assembler and the
MPLAB C18 C Compiler. It can link relocatable objects
from precompiled libraries, using directives from a
linker script.
The MPLIB Object Librarian manages the creation and
modification of library files of precompiled code. When
a routine from a library is called from a source file, only
the modules that contain that routine will be linked in
with the application. This allows large libraries to be
used efficiently in many different applications.
The object linker/library features include:
• Efficient linking of single libraries instead of many
smaller files
• Enhanced code maintainability by grouping
related modules together
• Flexible creation of libraries with easy module
listing, replacement, deletion and extraction
30.6 MPLAB Assembler, Linker and
Librarian for Various Device
Families
MPLAB Assembler produces relocatable machine
code from symbolic assembly language for PIC24,
PIC32 and dsPIC devices. MPLAB C Compiler uses
the assembler to produce its object file. The assembler
generates relocatable object files that can then be
archived or linked with other relocatable object files and
archives to create an executable file. Notable features
of the assembler include:
• Support for the entire device instruction set
• Support for fixed-point and floating-point data
• Command line interface
• Rich directive set
• Flexible macro language
• MPLAB IDE compatibility
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30.7 MPLAB SIM Software Simulator
The MPLAB SIM Software Simulator allows code
development in a PC-hosted environment by simulat-
ing the PIC MCUs and dsPIC® DSCs on an instruction
level. On any given instruction, the data areas can be
examined or modified and stimuli can be applied from
a comprehensive stimulus controller. Registers can be
logged to files for further run-time analysis. The trace
buffer and logic analyzer display extend the power of
the simulator to record and track program execution,
actions on I/O, most peripherals and internal registers.
The MPLAB SIM Software Simulator fully supports
symbolic debugging using the MPLAB C Compilers,
and the MPASM and MPLAB Assemblers. The soft-
ware simulator offers the flexibility to develop and
debug code outside of the hardware laboratory envi-
ronment, making it an excellent, economical software
development tool.
30.8 MPLAB REAL ICE In-Circuit
Emulator System
MPLAB REAL ICE In-Circuit Emulator System is
Microchip’s next generation high-speed emulator for
Microchip Flash DSC and MCU devices. It debugs and
programs PIC® Flash MCUs and dsPIC® Flash DSCs
with the easy-to-use, powerful graphical user interface of
the MPLAB Integrated Development Environment (IDE),
included with each kit.
The emulator is connected to the design engineer’s PC
using a high-speed USB 2.0 interface and is connected
to the target with either a connector compatible with in-
circuit debugger systems (RJ11) or with the new high-
speed, noise tolerant, Low-Voltage Differential Signal
(LVDS) interconnection (CAT5).
The emulator is field upgradable through future firmware
downloads in MPLAB IDE. In upcoming releases of
MPLAB IDE, new devices will be supported, and new
features will be added. MPLAB REAL ICE offers
significant advantages over competitive emulators
including low-cost, full-speed emulation, run-time
variable watches, trace analysis, complex breakpoints, a
ruggedized probe interface and long (up to three meters)
interconnection cables.
30.9 MPLAB ICD 3 In-Circuit Debugger
System
MPLAB ICD 3 In-Circuit Debugger System is Micro-
chip's most cost effective high-speed hardware
debugger/programmer for Microchip Flash Digital Sig-
nal Controller (DSC) and microcontroller (MCU)
devices. It debugs and programs PIC® Flash microcon-
trollers and dsPIC® DSCs with the powerful, yet easy-
to-use graphical user interface of MPLAB Integrated
Development Environment (IDE).
The MPLAB ICD 3 In-Circuit Debugger probe is con-
nected to the design engineer's PC using a high-speed
USB 2.0 interface and is connected to the target with a
connector compatible with the MPLAB ICD 2 or MPLAB
REAL ICE systems (RJ-11). MPLAB ICD 3 supports all
MPLAB ICD 2 headers.
30.10 PICkit 3 In-Circuit Debugger/
Programmer and
PICkit 3 Debug Express
The MPLAB PICkit 3 allows debugging and program-
ming of PIC® and dsPIC® Flash microcontrollers at a
most affordable price point using the powerful graphical
user interface of the MPLAB Integrated Development
Environment (IDE). The MPLAB PICkit 3 is connected
to the design engineer's PC using a full speed USB
interface and can be connected to the target via an
Microchip debug (RJ-11) connector (compatible with
MPLAB ICD 3 and MPLAB REAL ICE). The connector
uses two device I/O pins and the reset line to imple-
ment in-circuit debugging and In-Circuit Serial Pro-
gramming™.
The PICkit 3 Debug Express include the PICkit 3, demo
board and microcontroller, hookup cables and CDROM
with user’s guide, lessons, tutorial, compiler and
MPLAB IDE software.
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30.11 PICkit 2 Development
Programmer/Debugger and
PICkit 2 Debug Express
The PICkit™ 2 Development Programmer/Debugger is
a low-cost development tool with an easy to use inter-
face for programming and debugging Microchip’s Flash
families of microcontrollers. The full featured
Windows® programming interface supports baseline
(PIC10F, PIC12F5xx, PIC16F5xx), midrange
(PIC12F6xx, PIC16F), PIC18F, PIC24, dsPIC30,
dsPIC33, and PIC32 families of 8-bit, 16-bit, and 32-bit
microcontrollers, and many Microchip Serial EEPROM
products. With Microchip’s powerful MPLAB Integrated
Development Environment (IDE) the PICkit™ 2
enables in-circuit debugging on most PIC® microcon-
trollers. In-Circuit-Debugging runs, halts and single
steps the program while the PIC microcontroller is
embedded in the application. When halted at a break-
point, the file registers can be examined and modified.
The PICkit 2 Debug Express include the PICkit 2, demo
board and microcontroller, hookup cables and CDROM
with user’s guide, lessons, tutorial, compiler and
MPLAB IDE software.
30.12 MPLAB PM3 Device Programmer
The MPLAB PM3 Device Programmer is a universal,
CE compliant device programmer with programmable
voltage verification at VDDMIN and VDDMAX for
maximum reliability. It features a large LCD display
(128 x 64) for menus and error messages and a modu-
lar, detachable socket assembly to support various
package types. The ICSP™ cable assembly is included
as a standard item. In Stand-Alone mode, the MPLAB
PM3 Device Programmer can read, verify and program
PIC devices without a PC connection. It can also set
code protection in this mode. The MPLAB PM3
connects to the host PC via an RS-232 or USB cable.
The MPLAB PM3 has high-speed communications and
optimized algorithms for quick programming of large
memory devices and incorporates an MMC card for file
storage and data applications.
30.13 Demonstration/Development
Boards, Evaluation Kits, and
Starter Kits
A wide variety of demonstration, development and
evaluation boards for various PIC MCUs and dsPIC
DSCs allows quick application development on fully func-
tional systems. Most boards include prototyping areas for
adding custom circuitry and provide application firmware
and source code for examination and modification.
The boards support a variety of features, including LEDs,
temperature sensors, switches, speakers, RS-232
interfaces, LCD displays, potentiometers and additional
EEPROM memory.
The demonstration and development boards can be
used in teaching environments, for prototyping custom
circuits and for learning about various microcontroller
applications.
In addition to the PICDEM™ and dsPICDEM™ demon-
stration/development board series of circuits, Microchip
has a line of evaluation kits and demonstration software
for analog filter design, KEELOQ® security ICs, CAN,
IrDA®, PowerSmart battery management, SEEVAL®
evaluation system, Sigma-Delta ADC, flow rate
sensing, plus many more.
Also available are starter kits that contain everything
needed to experience the specified device. This usually
includes a single application and debug capability, all
on one board.
Check the Microchip web page (www.microchip.com)
for the complete list of demonstration, development
and evaluation kits.
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31.0 ELECTRICAL CHARAC TERISTICS
Absolute Maximum Ratings(†)
Ambient temperature under bias.............................................................................................................-40°C to +125°C
Storage temperature .............................................................................................................................. -65°C to +150°C
Voltage on any digital only I/O pin with respect to VSS (except VDD)........................................................... -0.3V to 7.5V
Voltage on MCLR with respect to VSS........................................................................................................... 0.3V to 9.0V
Voltage on any combined digital and analog pin with respect to VSS (except VDD and MCLR)...... -0.3V to (VDD + 0.3V)
Voltage on VDD with respect to VSS (with regulator enabled) ..................................................................... -0.3V to 5.5V
Voltage on VDD with respect to VSS (with regulator disabled)..................................................................... -0.3V to 3.6V
Total power dissipation (Note 1) ..................................................................................................................................1W
Maximum current out of VSS pin ...........................................................................................................................300 mA
Maximum current into VDD pin ..............................................................................................................................250 mA
Input clamp current, IIK (VI < 0 or VI > VDD) .......................................................................................................... ±20 mA
Output clamp current, IOK (VO < 0 or VO > VDD) ...................................................................................................±20 mA
Maximum output current sunk by PORTA<7:6> and any PORTB and PORTC I/O pins.........................................25 mA
Maximum output current sunk by any PORTD, PORTE and PORTJ I/O pins ..........................................................8 mA
Maximum output current sunk by PORTA<5:0> and any PORTF, PORTG and PORTH I/O pins ............................2 mA
Maximum output current sourced by PORTA<7:6> and any PORTB and PORTC I/O pins ...................................25 mA
Maximum output current sourced by any PORTD, PORTE and PORTJ I/O pins.....................................................8 mA
Maximum output current sourced by PORTA<5:0> and any PORTF, PORTG and PORTH I/O pins .......................2 mA
Maximum current sunk byall ports combined.......................................................................................................200 mA
Note 1: Power dissipation is calculated as follows:
Pdis = VDD x {IDD – IOH} + {(VDD – VOH) x IOH} + (VOL x IOL)
† NOTICE: Stresses above those listed under “Absolute Maximum Ratings” may cause permanent damage to the
device. This is a stress rating only and functional operation of the device at those or any other conditions above those
indicated in the operation listings of this specification is not implied. Exposure to maximum rating conditions for
extended periods may affect device reliability.
PIC18F87K22 FAMILY
DS39960C-page 486 2011 Microchip Technology Inc.
FIGURE 31-1: VOLTAGE-FREQUENCY GRAPH, REGULATOR ENABLED (INDUSTRIAL)(1)
FIGURE 31-2: VOLTAGE-FREQUENCY GRAPH, REGULATOR DISABLED (INDUSTRIAL)(1,2)
Frequency
Voltage (VDD)
6V
1.8V
64 MHz(1)
5V
4V
3V
5.5V
3V
04 MHz
PIC18F87K22 Family
Note 1: FMAX = 25 MHz in 8-Bit External Memory mode. For VDD values, 1.8V to 3V,
FMAX = (VDD – 1.8)/0.02 MHz.
2: FMAX = 64 MHz in all other modes. For VDD values, 1.8V to 3V, FMAX = (VDD – 1.72)/0.02 MHz.
Frequency
Volt age (VDD)
4V
1.8V
64 MHz
3.75V
3.25V
2.5V
3.6V
4 MHz
3V
Note 1: When the on-chip voltage regulator is disabled, VDD must be maintained so that VDD 3.6V.
2: For VDD values, 1.8V to 3V, FMAX = (VDD – 1.8)/0.02 MHz.
PIC18F87K22 Family
2011 Microchip Technology Inc. DS39960C-page 487
PIC18F87K22 FAMILY
31.1 DC Characteristics: Supply Voltage
PIC18F87K22 Family (Indust rial)
PIC18F87K22 Family
(Industrial) Standard Opera ting Conditions (unless otherwise stated)
Operating temperature -40°C TA +85°C for industrial
Param
No. Symbol Characteristic Min Typ Max Units Conditions
D001 VDD Supply Voltage 1.8
1.8
—
—
3.6
5.5
V
V
ENVREG tied to VSS
ENVREG tied to VDD
D001C AVDD Analog Supply Voltage VDD – 0.3 — VDD + 0.3 V
D001D AVSS Analog Ground Potential VSS – 0.3 — VSS + 0.3 V
D002 VDR RAM Data Retention
Voltage(1) 1.5 — — V
D003 VPOR VDD Start Voltage
to Ensure Internal
Power-on Reset Signal
——0.7VSee Section 5.3 “Power-on
Reset (POR)” for details
D004 SVDD VDD Rise Rate
to Ensure Internal
Power-on Reset Signal
0.05 — — V/ms See Section 5.3 “Power-on
Reset (POR)” for details
D005 BVDD Brown-out Reset
Voltage (High/Medium/
Low-Power mode)(2)
BORV<1:0> = 11(3)
BORV<1:0> = 10
BORV<1:0> = 01
BORV<1:0> = 00
1.69
1.88
2.53
2.82
1.8
2.0
2.7
3.0
1.91
2.12
2.86
3.18
Note 1: This is the limit to which VDD can be lowered in Sleep mode, or during a device Reset, without losing RAM data.
2: HP-BOR.
3: The device will operate normally until Brown-out Reset occurs, even though VDD may be below VDDMIN.
PIC18F87K22 FAMILY
DS39960C-page 488 2011 Microchip Technology Inc.
31.2 DC Characteristics: Power-Down and Supply Current
PIC18F87K22 Family (Industrial)
PIC18F87K22 Family
(Industrial) Standard Operating Conditions (unless otherwise stated)
Operating temperature -40°C TA +85°C for industrial
Param
No. Device Typ Max Units Conditions
Power-Down Current (IPD)(1)
All devices 10 500 nA -40°C
VDD = 1.8V(4)
(Sleep mode)
Regulator Disabled
20 500 nA +25°C
120 600 nA +60°C
630 1800 nA +85°C
All devices 50 700 nA -40°C
VDD = 3.3V(4)
(Sleep mode)
Regulator Disabled
60 700 nA +25°C
170 800 nA +60°C
700 2700 nA +85°C
All devices 350 1300 nA -40°C
VDD = 5V(5)
(Sleep mode)
Regulator Enabled
400 1400 nA +25°C
550 1500 nA +60°C
1350 4000 nA +85°C
Note 1: The power-down current in Sleep mode does not depend on the oscillator type. Power-down current is measured with
the part in Sleep mode, with all I/O pins in a high-impedance state and tied to VDD or VSS, and all features that add delta
current are disabled (such as WDT, SOSC oscillator, BOR, etc.).
2: The supply current is mainly a function of operating voltage, frequency and mode. Other factors, such as I/O pin loading
and switching rate, oscillator type and circuit, internal code execution pattern and temperature, also have an impact on
the current consumption.
The test conditions for all IDD measurements in active operation mode are:
OSC1 = external square wave, from rail-to-rail; all I/O pins tri-stated, pulled to VDD;
MCLR = VDD; WDT enabled/disabled as specified.
3: Standard, low-cost 32 kHz crystals have an operating temperature range of -10°C to +70°C. Extended temperature
crystals are available at a much higher cost.
4: Voltage regulator disabled (ENVREG = 0, tied to VSS, RETEN (CONFIG1L<0>) = 1).
5: Voltage regulator enabled (ENVREG = 1, tied to VDD, SRETEN (WDTCON<4>) = 1 and RETEN (CONFIG1L<0>) = 0).
2011 Microchip Technology Inc. DS39960C-page 489
PIC18F87K22 FAMILY
Supply Current (IDD)(2,3)
All devices 5.3 10 A -40°C
VDD = 1.8V(4)
Regulator Disabled
FOSC = 31 kHz
(RC_RUN mode,
LF-INTOSC)
5.5 10 A +25°C
5.5 10 A +85°C
All devices 10 15 A -40°C
VDD = 3.3V(4)
Regulator Disabled
10 16 A +25°C
11 17 A +85°C
All devices 70 180 A -40°C
VDD = 5V(5)
Regulator Enabled
80 185 A +25°C
90 190 A +85°C
All devices 410 850 A -40°C
VDD = 1.8V(4)
Regulator Disabled
FOSC = 1 MHz
(RC_RUN mode,
HF-INTOSC)
410 800 A +25°C
410 830 A +85°C
All devices 680 990 A -40°C
VDD = 3.3V(4)
Regulator Disabled
680 960 A +25°C
670 950 A +85°C
All devices 760 1400 A -40°C
VDD = 5V(5)
Regulator Enabled
780 1400 A +25°C
800 1500 A +85°C
All devices 760 1300 A -40°C
VDD = 1.8V(4)
Regulator Disabled
FOSC = 4 MHz
(RC_RUN mode,
HF-INTOSC)
760 1400 A +25°C
770 1500 A +85°C
All devices 1.4 2.5 mA -40°C
VDD = 3.3V(4)
Regulator Disabled
1.4 2.5 mA +25°C
1.4 2.5 mA +85°C
All devices 1.5 2.7 mA -40°C
VDD = 5V(5)
Regulator Enabled
1.5 2.7 mA +25°C
1.5 2.7 mA +85°C
31.2 DC Characteristics: Power-Down and Supply Current
PIC18F87K22 Family (Industrial) (Continued)
PIC18F87K22 Family
(Industrial) Standard Operating Conditions (unless otherwise stated)
Operating temperature -40°C TA +85°C for industrial
Param
No. Device Typ Max Units Conditions
Note 1: The power-down current in Sleep mode does not depend on the oscillator type. Power-down current is measured with
the part in Sleep mode, with all I/O pins in a high-impedance state and tied to VDD or VSS, and all features that add delta
current are disabled (such as WDT, SOSC oscillator, BOR, etc.).
2: The supply current is mainly a function of operating voltage, frequency and mode. Other factors, such as I/O pin loading
and switching rate, oscillator type and circuit, internal code execution pattern and temperature, also have an impact on
the current consumption.
The test conditions for all IDD measurements in active operation mode are:
OSC1 = external square wave, from rail-to-rail; all I/O pins tri-stated, pulled to VDD;
MCLR = VDD; WDT enabled/disabled as specified.
3: Standard, low-cost 32 kHz crystals have an operating temperature range of -10°C to +70°C. Extended temperature
crystals are available at a much higher cost.
4: Voltage regulator disabled (ENVREG = 0, tied to VSS, RETEN (CONFIG1L<0>) = 1).
5: Voltage regulator enabled (ENVREG = 1, tied to VDD, SRETEN (WDTCON<4>) = 1 and RETEN (CONFIG1L<0>) = 0).
PIC18F87K22 FAMILY
DS39960C-page 490 2011 Microchip Technology Inc.
Supply Current (IDD) Cont.(2,3)
All devices 2.1 5.5 A -40°C
VDD = 1.8V(4)
Regulator Disabled
FOSC = 31 kHz
(RC_IDLE mode,
LF-INTOSC)
2.1 5.7 A +25°C
2.2 6.0 A +85°C
All devices 3.7 7.5 A -40°C
VDD = 3.3V(4)
Regulator Disabled
3.9 7.8 A +25°C
3.9 8.5 A +85°C
All devices 70 180 A -40°C
VDD = 5V(5)
Regulator Enabled
80 190 A +25°C
80 200 A +85°C
All devices 330 650 A -40°C
VDD = 1.8V(4)
Regulator Disabled
FOSC = 1 MHz
(RC_IDLE mode,
HF-INTOSC)
330 640 A +25°C
330 630 A +85°C
All devices 520 850 A -40°C
VDD = 3.3V(4)
Regulator Disabled
520 900 A +25°C
520 850 A +85°C
All devices 590 940 A -40°C
VDD = 5V(5)
Regulator Enabled
600 960 A +25°C
620 990 A +85°C
All devices 470 770 A -40°C
VDD = 1.8V(4)
Regulator Disabled
FOSC = 4 MHz
(RC_IDLE mode,
internal HF-INTOSC)
470 770 A +25°C
460 760 A +85°C
All devices 800 1400 A -40°C
VDD = 3.3V(4)
Regulator Disabled
800 1350 A +25°C
790 1300 A +85°C
All devices 880 1600 A -40°C
VDD = 5V(5)
Regulator Enabled
890 1700 A +25°C
910 1800 A +85°C
31.2 DC Characteristics: Power-Down and Supply Current
PIC18F87K22 Family (Industrial) (Continued)
PIC18F87K22 Family
(Industrial) Standard Operating Conditions (unless otherwise stated)
Operating temperature -40°C TA +85°C for industrial
Param
No. Device Typ Max Units Conditions
Note 1: The power-down current in Sleep mode does not depend on the oscillator type. Power-down current is measured with
the part in Sleep mode, with all I/O pins in a high-impedance state and tied to VDD or VSS, and all features that add delta
current are disabled (such as WDT, SOSC oscillator, BOR, etc.).
2: The supply current is mainly a function of operating voltage, frequency and mode. Other factors, such as I/O pin loading
and switching rate, oscillator type and circuit, internal code execution pattern and temperature, also have an impact on
the current consumption.
The test conditions for all IDD measurements in active operation mode are:
OSC1 = external square wave, from rail-to-rail; all I/O pins tri-stated, pulled to VDD;
MCLR = VDD; WDT enabled/disabled as specified.
3: Standard, low-cost 32 kHz crystals have an operating temperature range of -10°C to +70°C. Extended temperature
crystals are available at a much higher cost.
4: Voltage regulator disabled (ENVREG = 0, tied to VSS, RETEN (CONFIG1L<0>) = 1).
5: Voltage regulator enabled (ENVREG = 1, tied to VDD, SRETEN (WDTCON<4>) = 1 and RETEN (CONFIG1L<0>) = 0).
2011 Microchip Technology Inc. DS39960C-page 491
PIC18F87K22 FAMILY
Supply Current (IDD) Cont.(2,3)
All devices 130 390 A -40°C
VDD = 1.8V(4)
Regulator Disabled
FOSC = 1 MHZ
(PRI_RUN mode,
EC oscillator)
130 390 A +25°C
130 390 A +85°C
All devices 270 790 A -40°C
VDD = 3.3V(4)
Regulator Disabled
270 790 A +25°C
270 790 A +85°C
All devices 430 990 A -40°C
VDD = 5V(5)
Regulator Enabled
450 980 A +25°C
460 980 A +85°C
All devices 430 860 A -40°C
VDD = 1.8V(4)
Regulator Disabled
FOSC = 4 MHz
(PRI_RUN mode,
EC oscillator)
530 900 A +25°C
490 880 A +85°C
All devices 850 1750 A -40°C
VDD = 3.3V(4)
Regulator Disabled
850 1700 A +25°C
850 1800 A +85°C
All devices 1.1 2.7 mA -40°C
VDD = 5V(5)
Regulator Enabled
1.1 2.6 mA +25°C
1.1 2.6 mA +85°C
All devices 12 19 mA -40°C
VDD = 3.3V(4)
Regulator Disabled FOSC = 64 MHZ
(PRI_RUN mode,
EC oscillator)
12 19 mA +25°C
12 19 mA +85°C
All devices 13 20 mA -40°C
VDD = 5V(5)
Regulator Enabled
13 20 mA +25°C
13 20 mA +85°C
31.2 DC Characteristics: Power-Down and Supply Current
PIC18F87K22 Family (Industrial) (Continued)
PIC18F87K22 Family
(Industrial) Standard Operating Conditions (unless otherwise stated)
Operating temperature -40°C TA +85°C for industrial
Param
No. Device Typ Max Units Conditions
Note 1: The power-down current in Sleep mode does not depend on the oscillator type. Power-down current is measured with
the part in Sleep mode, with all I/O pins in a high-impedance state and tied to VDD or VSS, and all features that add delta
current are disabled (such as WDT, SOSC oscillator, BOR, etc.).
2: The supply current is mainly a function of operating voltage, frequency and mode. Other factors, such as I/O pin loading
and switching rate, oscillator type and circuit, internal code execution pattern and temperature, also have an impact on
the current consumption.
The test conditions for all IDD measurements in active operation mode are:
OSC1 = external square wave, from rail-to-rail; all I/O pins tri-stated, pulled to VDD;
MCLR = VDD; WDT enabled/disabled as specified.
3: Standard, low-cost 32 kHz crystals have an operating temperature range of -10°C to +70°C. Extended temperature
crystals are available at a much higher cost.
4: Voltage regulator disabled (ENVREG = 0, tied to VSS, RETEN (CONFIG1L<0>) = 1).
5: Voltage regulator enabled (ENVREG = 1, tied to VDD, SRETEN (WDTCON<4>) = 1 and RETEN (CONFIG1L<0>) = 0).
PIC18F87K22 FAMILY
DS39960C-page 492 2011 Microchip Technology Inc.
Supply Current (IDD) Cont.(2,3)
All devices 3.3 5.6 mA -40°C
VDD = 3.3V(4)
Regulator Disabled FOSC = 16 MHZ,
(PRI_RUN mode, 4 MHz
EC oscillator with PLL)
3.3 5.5 mA +25°C
3.3 5.5 mA +85°C
All devices 3.5 5.9 mA -40°C
VDD = 5V(5)
Regulator Enabled
3.5 5.8 mA +25°C
3.5 5.8 mA +85°C
All devices 12 18 mA -40°C
VDD = 3.3V(4)
Regulator Disabled FOSC = 64 MHZ,
(PRI_RUN mode, 16 MHz
EC oscillator with PLL)
12 18 mA +25°C
12 18 mA +85°C
All devices 13 20 mA -40°C
VDD = 5V(5)
Regulator Enabled
13 20 mA +25°C
13 20 mA +85°C
31.2 DC Characteristics: Power-Down and Supply Current
PIC18F87K22 Family (Industrial) (Continued)
PIC18F87K22 Family
(Industrial) Standard Operating Conditions (unless otherwise stated)
Operating temperature -40°C TA +85°C for industrial
Param
No. Device Typ Max Units Conditions
Note 1: The power-down current in Sleep mode does not depend on the oscillator type. Power-down current is measured with
the part in Sleep mode, with all I/O pins in a high-impedance state and tied to VDD or VSS, and all features that add delta
current are disabled (such as WDT, SOSC oscillator, BOR, etc.).
2: The supply current is mainly a function of operating voltage, frequency and mode. Other factors, such as I/O pin loading
and switching rate, oscillator type and circuit, internal code execution pattern and temperature, also have an impact on
the current consumption.
The test conditions for all IDD measurements in active operation mode are:
OSC1 = external square wave, from rail-to-rail; all I/O pins tri-stated, pulled to VDD;
MCLR = VDD; WDT enabled/disabled as specified.
3: Standard, low-cost 32 kHz crystals have an operating temperature range of -10°C to +70°C. Extended temperature
crystals are available at a much higher cost.
4: Voltage regulator disabled (ENVREG = 0, tied to VSS, RETEN (CONFIG1L<0>) = 1).
5: Voltage regulator enabled (ENVREG = 1, tied to VDD, SRETEN (WDTCON<4>) = 1 and RETEN (CONFIG1L<0>) = 0).
2011 Microchip Technology Inc. DS39960C-page 493
PIC18F87K22 FAMILY
Supply Current (IDD) Cont.(2,3)
All devices 42 73 A -40°C
VDD = 1.8V(4)
Regulator Disabled
FOSC = 1 MHz
(PRI_IDLE mode,
EC oscillator)
42 73 A +25°C
43 74 A +85°C
All devices 110 190 A -40°C
VDD = 3.3V(4)
Regulator Disabled
110 195 A +25°C
110 195 A +85°C
All devices 280 450 A -40°C
VDD = 5V(5)
Regulator Enabled
290 440 A +25°C
300 460 A +85°C
All devices 160 360 A -40°C
VDD = 1.8V(4)
Regulator Disabled
FOSC = 4 MHz
(PRI_IDLE mode,
EC oscillator)
160 360 A +25°C
170 370 A +85°C
All devices 330 650 A -40°C
VDD = 3.3V(4)
Regulator Disabled
340 660 A +25°C
340 660 A +85°C
All devices 510 900 A -40°C
VDD = 5V(5)
Regulator Enabled
520 950 A +25°C
540 990 A +85°C
All devices 4.7 9 mA -40°C
VDD = 3.3V(4)
Regulator Disabled FOSC = 64 MHz
(PRI_IDLE mode,
EC oscillator)
4.8 9 mA +25°C
4.8 9 mA +85°C
All devices 5.1 11 mA -40°C
VDD = 5V(5)
Regulator Enabled
5.1 11 mA +25°C
5.2 12 mA +85°C
31.2 DC Characteristics: Power-Down and Supply Current
PIC18F87K22 Family (Industrial) (Continued)
PIC18F87K22 Family
(Industrial) Standard Operating Conditions (unless otherwise stated)
Operating temperature -40°C TA +85°C for industrial
Param
No. Device Typ Max Units Conditions
Note 1: The power-down current in Sleep mode does not depend on the oscillator type. Power-down current is measured with
the part in Sleep mode, with all I/O pins in a high-impedance state and tied to VDD or VSS, and all features that add delta
current are disabled (such as WDT, SOSC oscillator, BOR, etc.).
2: The supply current is mainly a function of operating voltage, frequency and mode. Other factors, such as I/O pin loading
and switching rate, oscillator type and circuit, internal code execution pattern and temperature, also have an impact on
the current consumption.
The test conditions for all IDD measurements in active operation mode are:
OSC1 = external square wave, from rail-to-rail; all I/O pins tri-stated, pulled to VDD;
MCLR = VDD; WDT enabled/disabled as specified.
3: Standard, low-cost 32 kHz crystals have an operating temperature range of -10°C to +70°C. Extended temperature
crystals are available at a much higher cost.
4: Voltage regulator disabled (ENVREG = 0, tied to VSS, RETEN (CONFIG1L<0>) = 1).
5: Voltage regulator enabled (ENVREG = 1, tied to VDD, SRETEN (WDTCON<4>) = 1 and RETEN (CONFIG1L<0>) = 0).
PIC18F87K22 FAMILY
DS39960C-page 494 2011 Microchip Technology Inc.
Supply Current (IDD) Cont.(2,3)
All devices 3.7 8.5 µA -40°C
VDD = 1.8V(4)
Regulator Disabled
FOSC = 32 kHz(3)
(SEC_RUN mode,
SOSCSEL = 01)
5.4 10 µA +25°C
6.6 13 µA +85°C
All devices 8.7 18 µA -40°C
VDD = 3.3V(4)
Regulator Disabled
10 20 µA +25°C
12 23 µA +85°C
All devices 60 160 µA -40°C
VDD = 5V(5)
Regulator Enabled
90 190 µA +25°C
100 240 µA +85°C
All devices 1.2 4 µA -40°C
VDD = 1.8V(4)
Regulator Disabled
FOSC = 32 kHz(3)
(SEC_IDLE mode,
SOSCSEL = 01)
1.7 5 µA +25°C
2.6 6 µA +85°C
All devices 1.6 7 µA -40°C
VDD = 3.3V(4)
Regulator Disabled
2.8 9 µA +25°C
4.1 10 µA +85°C
All devices 60 150 µA -40°C
VDD = 5V(5)
Regulator Enabled
80 180 µA +25°C
100 240 µA +85°C
31.2 DC Characteristics: Power-Down and Supply Current
PIC18F87K22 Family (Industrial) (Continued)
PIC18F87K22 Family
(Industrial) Standard Operating Conditions (unless otherwise stated)
Operating temperature -40°C TA +85°C for industrial
Param
No. Device Typ Max Units Conditions
Note 1: The power-down current in Sleep mode does not depend on the oscillator type. Power-down current is measured with
the part in Sleep mode, with all I/O pins in a high-impedance state and tied to VDD or VSS, and all features that add delta
current are disabled (such as WDT, SOSC oscillator, BOR, etc.).
2: The supply current is mainly a function of operating voltage, frequency and mode. Other factors, such as I/O pin loading
and switching rate, oscillator type and circuit, internal code execution pattern and temperature, also have an impact on
the current consumption.
The test conditions for all IDD measurements in active operation mode are:
OSC1 = external square wave, from rail-to-rail; all I/O pins tri-stated, pulled to VDD;
MCLR = VDD; WDT enabled/disabled as specified.
3: Standard, low-cost 32 kHz crystals have an operating temperature range of -10°C to +70°C. Extended temperature
crystals are available at a much higher cost.
4: Voltage regulator disabled (ENVREG = 0, tied to VSS, RETEN (CONFIG1L<0>) = 1).
5: Voltage regulator enabled (ENVREG = 1, tied to VDD, SRETEN (WDTCON<4>) = 1 and RETEN (CONFIG1L<0>) = 0).
2011 Microchip Technology Inc. DS39960C-page 495
PIC18F87K22 FAMILY
Module Differential Currents (IWDT, IBOR, IHLVD, IOSCB, IAD)
D022
(IWDT)
Watchdog Timer
All devices 0.3 1 A -40°C VDD = 1.8V(4)
Regulator Disabled
0.3 1 A +25°C
0.3 1 A +85°C
All devices 0.6 1.9 A -40°C VDD = 3.3V(4)
Regulator Disabled
0.6 1.8 A +25°C
0.6 1.8 A +85°C
All Devices 0.6 1.8 A -40°C VDD = 5V(5)
Regulator Enabled
0.6 1.8 A +25°C
0.6 1.8 A +85°C
D022A Brown-out R eset
(IBOR) All devices 4.6 19 A -40°C VDD = 3.3V(4)
Regulator Disabled High-Power BOR
4.5 20 A +25°C
4.7 20 A +85°C
All devices 4.2 20 A -40°C VDD = 5V(5)
Regulator Enabled
High-Power BOR
4.3 20 A +25°C
4.4 20 A +85°C
D022B High/Low- Voltage D e tec t
(IHLVD) All devices 3.8 9 A -40°C VDD = 1.8V(4)
Regulator Disabled
4.2 9 A +25°C
4.3 10 A +85°C
All devices 4.5 11 A -40°C VDD = 3.3V(4)
Regulator Disabled
4.8 12 A +25°C
4.8 12 A +85°C
All devices 4.9 13 A -40°C VDD = 5V(5)
Regulator Enabled
4.9 13 A +25°C
4.9 13 A +85°C
31.2 DC Characteristics: Power-Down and Supply Current
PIC18F87K22 Family (Industrial) (Continued)
PIC18F87K22 Family
(Industrial) Standard Operating Conditions (unless otherwise stated)
Operating temperature -40°C TA +85°C for industrial
Param
No. Device Typ Max Units Conditions
Note 1: The power-down current in Sleep mode does not depend on the oscillator type. Power-down current is measured with
the part in Sleep mode, with all I/O pins in a high-impedance state and tied to VDD or VSS, and all features that add delta
current are disabled (such as WDT, SOSC oscillator, BOR, etc.).
2: The supply current is mainly a function of operating voltage, frequency and mode. Other factors, such as I/O pin loading
and switching rate, oscillator type and circuit, internal code execution pattern and temperature, also have an impact on
the current consumption.
The test conditions for all IDD measurements in active operation mode are:
OSC1 = external square wave, from rail-to-rail; all I/O pins tri-stated, pulled to VDD;
MCLR = VDD; WDT enabled/disabled as specified.
3: Standard, low-cost 32 kHz crystals have an operating temperature range of -10°C to +70°C. Extended temperature
crystals are available at a much higher cost.
4: Voltage regulator disabled (ENVREG = 0, tied to VSS, RETEN (CONFIG1L<0>) = 1).
5: Voltage regulator enabled (ENVREG = 1, tied to VDD, SRETEN (WDTCON<4>) = 1 and RETEN (CONFIG1L<0>) = 0).
PIC18F87K22 FAMILY
DS39960C-page 496 2011 Microchip Technology Inc.
D025
(IRTCC)
Real-Time Clock/
Cale ndar with SOSC
All devices 0.7 2.7 µA -40°C
VDD = 1.8V(4)
Regulator Disabled
32.768 kHz,
SOSCRUN = 1
0.7 2.8 µA +25°C
1.1 2.8 µA +60°C
1.1 +85°C2.9 µA
All devices 1.2 2.9 µA -40°C
VDD = 3.3V(4)
Regulator Disabled
1.1 2.8 µA +25°C
2 4.6 µA +60°C
24.8
A +85°C
All devices 1.5 4.4 A -40°C
VDD = 5V(5)
Regulator Enabled
1.5 4.4 A +25°C
1.7 4.7 µA +60°C
1.7 4.7 A +85°C
31.2 DC Characteristics: Power-Down and Supply Current
PIC18F87K22 Family (Industrial) (Continued)
PIC18F87K22 Family
(Industrial) Standard Operating Conditions (unless otherwise stated)
Operating temperature -40°C TA +85°C for industrial
Param
No. Device Typ Max Units Conditions
Note 1: The power-down current in Sleep mode does not depend on the oscillator type. Power-down current is measured with
the part in Sleep mode, with all I/O pins in a high-impedance state and tied to VDD or VSS, and all features that add delta
current are disabled (such as WDT, SOSC oscillator, BOR, etc.).
2: The supply current is mainly a function of operating voltage, frequency and mode. Other factors, such as I/O pin loading
and switching rate, oscillator type and circuit, internal code execution pattern and temperature, also have an impact on
the current consumption.
The test conditions for all IDD measurements in active operation mode are:
OSC1 = external square wave, from rail-to-rail; all I/O pins tri-stated, pulled to VDD;
MCLR = VDD; WDT enabled/disabled as specified.
3: Standard, low-cost 32 kHz crystals have an operating temperature range of -10°C to +70°C. Extended temperature
crystals are available at a much higher cost.
4: Voltage regulator disabled (ENVREG = 0, tied to VSS, RETEN (CONFIG1L<0>) = 1).
5: Voltage regulator enabled (ENVREG = 1, tied to VDD, SRETEN (WDTCON<4>) = 1 and RETEN (CONFIG1L<0>) = 0).
2011 Microchip Technology Inc. DS39960C-page 497
PIC18F87K22 FAMILY
31.3 DC Characteristics: PIC18F87K22 Family (Industria l)
DC CHARACTERISTICS Standard Operating Conditions (unless otherwise stated)
Operating temperature -40°C TA +85°C for industrial
Param
No. Symbol Characteristic Min Max Units Conditions
VIL Input Low Volta ge
All I/O Ports:
D030 with TTL Buffer VSS 0.15 VDD VVDD < 4.5V
D031 with Schmitt Trigger Buffer
RC3, RC4
RD5, RD6
—
VSS
VSS
0.8
0.2 VDD
1.5
V
V
V
4.5V VDD 5.5V
VDD < 4.5
4.5V VDD 5.5V
D032 MCLR VSS 0.2 VDD V
D033 OSC1 VSS 0.2 VDD V LP, XT, HS modes
D033A
D034
OSC1
SOSCI
VSS
VSS
0.2 VDD
0.3 VDD
V
V
EC modes
VIH Input High Volt age
I/O Ports with Analog Functions:
D040 with TTL Buffer 0.25 VDD
2.0
VDD
VDD
V
V
VDD < 4.5V
4.5V VDD 5.5V
D041 with Schmitt Trigger Buffer
RC3, RC4
RD5, RD6
0.8
0.7 VDD
3V
VDD
VDD
5.5
V
V
V
VDD < 4.5V
VDD < 4.5V
4.5V VDD 5.5V
D042 MCLR 0.8 VDD VDD V
D043 OSC1 0.9 VDD VDD V RC mode
D043A
D044
OSC1
SOSCI
0.7 VDD
0.7 VDD
VDD
VDD
V
V
HS mode
IIL Input Leakage Current (1)
D060 I/O Ports ±50 ±200 nA VSS VPIN VDD,
Pin at high-impedance
D061 MCLR —±5AVss VPIN VDD, +85°C
D063 OSC1 — ±5 AVss VPIN VDD
IPU Weak Pull-up Current
D070 IPURB PORTB Weak Pull-up Current 50 400 AVDD = 3.3V, VPIN = VSS
Note 1: Negative current is defined as current sourced by the pin.
PIC18F87K22 FAMILY
DS39960C-page 498 2011 Microchip Technology Inc.
31.4 DC Characteristics: CTMU Current Source Specifications
VOL Output Low Voltage
D080 I/O Ports:
PORTA, PORTB, PORTC — 0.6 V IOL = 8.5 mA, VDD = 4.5V,
-40C to +85C
PORTD, PORTE, PORTF, PORTG,
PORTH, PORTJ
—0.6VI
OL = 3.5 mA, VDD = 4.5V,
-40C to +85C
VOH Output High Voltage(1)
D090 I/O Ports: V
PORTA, PORTB, PORTC VDD – 0.7 — V IOH = -3 mA, VDD = 4.5V,
-40C to +85C
PORTD, PORTE, PORTF, PORTG,
PORTH, PORTJ
VDD – 0.7 — V IOH = -2 mA, VDD = 4.5V,
-40C to +85C
Capacitive Loading Specs
on Output Pins
D100(4) COSC2 OSC2 Pin — 20 pF In HS mode when
external clock is used to
drive OSC1
D101 CIO All I/O Pins and OSC2 — 50 pF To meet the AC Timing
Specifications
D102 CBSCLx, SDAx — 400 pF I2C™ Specification
DC CHARACTERISTICS Standard Operating Conditions: 1.8V to 3.6V (unless otherwise stated)
Operating temperature -40°C TA +85°C for Industrial
Param
No. Sym Characteristic Min Typ(1) Max Units Conditions
IOUT1 CTMU Current Source,
Base Range
— 550 — nA CTMUICON<1:0> = 01
IOUT2 CTMU Current Source,
10x Range
—5.5—A CTMUICON<1:0> = 10
IOUT3 CTMU Current Source,
100x Range
—55—A CTMUICON<1:0> = 11
Note 1: Nominal value at center point of current trim range (CTMUICON<7:2> = 000000).
31.3 DC Characteristics: PIC18F87K22 Family (Industria l) (Continued)
DC CHARACTERISTICS Standard Operating Conditions (unless otherwise stated)
Operating temperature -40°C TA +85°C for industrial
Param
No. Symbol Characteristic Min Max Units Conditions
Note 1: Negative current is defined as current sourced by the pin.
2011 Microchip Technology Inc. DS39960C-page 499
PIC18F87K22 FAMILY
TABLE 31-1: MEMORY PROGRAMMING REQUIREMENTS
DC CHARACTERISTICS Standard Operating Conditions (unless otherwise stated)
Operating temperature -40°C TA +85°C for industrial
Param
No. Sym Characteristic Min Typ† Max Units Conditions
Internal Program Memory
Programming Specifications(1)
D110 VPP Voltage on MCLR/VPP/RE5 pin VDD + 1.5 — 10 V (Note 3, Note 4)
D113 IDDP Supply Current during
Programming
——10mA
Data EEPROM Memory (Note 2)
D120 EDByte Endurance 100K 1000K — E/W -40C to +85C
D121 VDRW VDD for Read/Write 1.8 — 5.5 V Using EECON to read/
write, ENVREG tied to VDD
1.8 — 3.6 V Using EECON to read/
write, ENVREG tied to VSS
D122 TDEW Erase/Write Cycle Time — 4 — ms
D123 TRETD Characteristic Retention 40 — — Year Provided no other
specifications are violated
D124 TREF Number of Total Erase/Write
Cycles before Refresh(2) 1M 10M — E/W -40°C to +85°C
Program Flash Memory
D130 EPCell Endurance 1K 10K — E/W -40C to +85C
D131 VPR VDD for Read 1.8 — 5.5 V ENVREG tied to VDD
1.8 — 3.6 V ENVREG tied to VSS
D132B VPEW Voltage for Self-Timed Erase or
Write Operations
VDD 1.8 — 5.5 V ENVREG tied to VDD
D133A TIW Self-Timed Write Cycle Time — 2 — ms
D134 TRETD Characteristic Retention 40 — — Year Provided no other
specifications are violated
D135 IDDP Supply Current during
Programming
——10mA
D140 TWE Writes per Erase Cycle — — 1 For each physical address
† Data in “Typ” column is at 3.3V, 25°C unless otherwise stated. These parameters are for design guidance
only and are not tested.
Note 1: These specifications are for programming the on-chip program memory through the use of table write
instructions.
2: Refer to Section 9.8 “Using the Data EEPROM” for a more detailed discussion on data EEPROM
endurance.
3: Required only if Single-Supply Programming is disabled.
4: The MPLAB® ICD 2 does not support variable VPP output. Circuitry to limit the MPLAB ICD 2 VPP voltage
must be placed between the MPLAB ICD 2 and target system when programming or debugging with the
MPLAB ICD 2.
PIC18F87K22 FAMILY
DS39960C-page 500 2011 Microchip Technology Inc.
TABLE 31-2: COMPARATO R SPECIFICATIONS
TABLE 31-3: VOLTAGE REFERENCE SPECIFICATIONS
TABLE 31-4: INTERNAL VOLTAGE REGULATOR SPECIFICATIONS
Operating Conditions: 1.8V VDD 5V, -40°C TA +85°C (unless otherwise stated)
Param
No. Sym Characteristics Min Typ Max Units Comments
D300 VIOFF Input Offset Voltage — ±5.0 40 mV
D301 VICM Input Common Mode Voltage — — AVDD – 1.5 V
D302 CMRR Common Mode Rejection Ratio 55 — — dB
D303 TRESP Response Time(1) — 150 400 ns
D304 TMC2OV Comparator Mode Change to
Output Valid*
—— 10 s
Note 1: Response time measured with one comparator input at (AVDD – 1.5)/2, while the other input transitions
from VSS to VDD.
Operating Condit ions : 1.8V VDD 5V, -40°C TA +85°C (unless otherwise stated)
Param
No. Sym Characteristics Min Typ Max Units Comments
D310 VRES Resolution —
V
DD
/32
—LSb
D311 VRAA Absolute Accuracy — — 1/2 LSb
D312 VRUR Unit Resistor Value (R) — 2k —
D313 TSET Settling Time(1) — — 10 s
Note 1: Settling time measured while CVRR = 1 and CVR<3:0> transitions from ‘0000’ to ‘1111’.
Operating Condit ions : -40°C TA +85°C (unless otherwise stated)
Param
No. Sym Characteristics Min Typ Max Units Comments
VRGOUT Regulator Output Voltage — 3.3 — V
CEFC External Filter Capacitor Value 4.7 10 — F Capacitor must be
low-ESR, a low series
resistance (< 5)
2011 Microchip Technology Inc. DS39960C-page 501
PIC18F87K22 FAMILY
31.5 AC (Timin g) Characteristics
31.5.1 TIMING PARAMETER SYMBOLOGY
The timing parameter symbols have been created
following one of the following formats:
1. TppS2ppS 3. TCC:ST (I2C specifications only)
2. TppS 4. Ts (I2C specifications only)
T
F Frequency T Time
Lowercase letters (pp) and their meanings:
pp
cc CCP1 osc OSC1
ck CLKO rd RD
cs CS rw RD or WR
di SDI sc SCK
do SDO ss SS
dt Data in t0 T0CKI
io I/O port t1 T1CKI
mc MCLR wr WR
Uppercase letters and their meanings:
S
F Fall P Period
HHigh RRise
I Invalid (High-impedance) V Valid
L Low Z High-impedance
I2C only
AA output access High High
BUF Bus free Low Low
T
CC:ST (I2C specifications only)
CC
HD Hold SU Setup
ST
DAT DATA input hold STO Stop condition
STA Start condition
PIC18F87K22 FAMILY
DS39960C-page 502 2011 Microchip Technology Inc.
31.5.2 TIMING CONDITIONS
The temperature and voltages specified in Table 3 1-5
apply to all timing specifications unless otherwise
noted. Figure 31-3 specifies the load conditions for the
timing specifications.
TABLE 31-5: TEMPERATURE AND VOLTAGE SPECIFICATIONS – AC
FIGURE 31-3: LOAD CONDITIONS FOR DEVICE TIMING SPECIFICATIONS
AC CHARACTERISTICS S tandard Operating Co nditi ons (unle ss otherwise stated )
Operating temperature -40°C TA +85°C for industrial
Operating voltage VDD range as described in Section 31.1 and Section 31.3.
VDD/2
CL
RL
Pin Pin
VSS VSS
CL
RL= 464
CL= 50 pF for all pins except OSC2/CLKO/RA6
and including D and E outputs as ports
CL= 15 pF for OSC2/CLKO/RA6
Load Condition 1 Load Condition 2
2011 Microchip Technology Inc. DS39960C-page 503
PIC18F87K22 FAMILY
31.5.3 TIMING DIAGRAMS AND
SPECIFICATIONS
FIGURE 31-4: EX TER NAL CLOCK TIMING
TABLE 31-6: EXTERNAL CLOCK TIMING REQUIREMENTS
Param.
No. Symbol Characteristic Min Max Units Conditions
1A FOSC External CLKIN
Frequency(1) DC 64 MHz EC, ECIO Oscillator mode
Oscillator Frequency(1) DC 4 MHz RC Oscillator mode
0.1 4 MHz XT Oscillator mode
4 16 MHz HS Oscillator mode
4 16 MHz HS + PLL Oscillator mode
5 33 kHz LP Oscillator mode
1T
OSC External CLKIN Period(1) 15.6 — ns EC, ECIO Oscillator mode
Oscillator Period(1) 250 — ns RC Oscillator mode
250 10,000 ns XT Oscillator mode
40
62.5
250
250
ns
ns
HS Oscillator mode
HS + PLL Oscillator mode
5200
s LP Oscillator mode
2T
CY Instruction Cycle Time(1) 62.5 — ns TCY = 4/FOSC
3T
OSL,
T
OSH
External Clock in (OSC1)
High or Low Time
30 — ns XT Oscillator mode
2.5 — s LP Oscillator mode
10 — ns HS Oscillator mode
4T
OSR,
T
OSF
External Clock in (OSC1)
Rise or Fall Time
— 20 ns XT Oscillator mode
— 50 ns LP Oscillator mode
— 7.5 ns HS Oscillator mode
Note 1: Instruction cycle period (TCY) equals four times the input oscillator time base period for all configurations
except PLL. All specified values are based on characterization data for that particular oscillator type under
standard operating conditions with the device executing code. Exceeding these specified limits may result
in an unstable oscillator operation and/or higher than expected current consumption. All devices are tested
to operate at “min.” values with an external clock applied to the OSC1/CLKIN pin. When an external clock
input is used, the “max.” cycle time limit is “DC” (no clock) for all devices.
OSC1
CLKO
Q4 Q1 Q2 Q3 Q4 Q1
1
2
3344
PIC18F87K22 FAMILY
DS39960C-page 504 2011 Microchip Technology Inc.
TABLE 31-7: PLL CLOCK TIMING SPECIFICATIONS (VDD = 1.8V TO 5.5V)
TABLE 31-8: INTERNAL RC ACCURACY (INTOSC)
Param
No. Sym Characteristic Min Typ† Max Units Conditions
F10 FOSC Oscillator Frequency Range 4 — 5 MHz VDD = 1.8-.5V
4—16MHzV
DD = 3.0-.5V,
-40°C to +85°C
F11 FSYS On-Chip VCO System Frequency 16 — 20 MHz VDD = 1.8-.5V
16 — 64 MHz VDD = 3.0-.5V,
-40°C to +85°C
F12 trc PLL Start-up Time (Lock Time) — — 2 ms
F13 CLK CLKOUT Stability (Jitter) -2 — +2 %
† Data in “Typ” column is at 3V, 25C unless otherwise stated. These parameters are for design guidance
only and are not tested.
PIC18F87K22 Family Standard Operating Conditions (unless otherwise stated)
Operating temperature -40°C TA +85°C
Param
No. Min Typ Max Units Conditions
OA1 HFINTOSC/MFINTOSC Accuracy @ Freq = 16 MHz, 8 MHz, 4 MHz, 2 MHz, 1 MHz, 500 kHz, 250 kHz(1)
-2 — 2 % +25°C VDD = 3.0-5.0V
-5 — 5 % -40°C to +85°C VDD = 3.0-5.0V
-5 — 5 % -40°C to +85°C VDD = 1.8-5.0V
OA2 LFINTOSC Accura cy @ Freq = 31 kHz
-15 — 15 % -40°C to +85°C VDD = 1.8-5.0V
Note 1: Frequency calibrated at 25°C. OSCTUNE register can be used to compensate for temperature drift.
2011 Microchip Technology Inc. DS39960C-page 505
PIC18F87K22 FAMILY
FIGURE 31-5: CLKO AND I/O TIMING
TABLE 31-9: CLKO AND I/O TIMING REQUIREMENTS
Param
No. Symbol Characteristic Min Typ Max Units Conditions
10 TOSH2CKLOSC1 to CLKO —75200ns(Note 1)
11 TOSH2CKHOSC1 to CLKO —75200ns(Note 1)
12 TCKRCLKO Rise Time — 15 30 ns(Note 1)
13 TCKF CLKO Fall Time — 15 30 ns (Note 1)
14 TCKL2IOVCLKO to Port Out Valid — — 0.5 TCY + 20 ns
15 TIOV2CKH Port In Valid before CLKO 0.25 TCY + 25 — — ns
16 TCKH2IOI Port In Hold after CLKO 0——ns
17 TOSH2IOVOSC1 (Q1 cycle) to Port Out Valid — 50 150 ns
18 TOSH2IOIOSC1 (Q2 cycle) to Port Input Invalid
(I/O in hold time)
100 — — ns
19 TIOV2OSH Port Input Valid to OSC1
(I/O in setup time)
0——ns
20 TIOR Port Output Rise Time — 10 25 ns
21 TIOF Port Output Fall Time — 10 25 ns
22† TINP INTx pin High or Low Time 20 — — ns
23† TRBP RB<7:4> Change INTx High or Low
Time
TCY ——ns
† These parameters are asynchronous events not related to any internal clock edges.
Note 1: Measurements are taken in EC mode, where CLKO output is 4 x TOSC.
Note: Refer to Figure 31-3 for load conditions.
OSC1
CLKO
I/O pin
(Input)
I/O pin
(Output)
Q4 Q1 Q2 Q3
10
13
14
17
20, 21
19 18
15
11
12
16
Old Value New Value
PIC18F87K22 FAMILY
DS39960C-page 506 2011 Microchip Technology Inc.
FIGURE 31-6: PROGRAM MEMORY FETCH TIMING DIAGRAM (8-BIT)
TABLE 31-10: PROGRAM MEMORY FETCH TIMING REQUIREMENTS (8-B IT)
Param
No Symbol Characteristics Min Typ Max Units
150 TadV2aIL Address Out Valid to ALE (address setup time) 0.25 TCY – 10 — — ns
151 TaIL2adl ALE to Address Out Invalid (address hold time) 5 — — ns
153 BA01 BA0 to Most Significant Data Valid 0.125 TCY ——ns
154 BA02 BA0 to Least Significant Data Valid 0.125 TCY ——ns
155 TaIL2oeL ALE to OE 0.125 TCY ——ns
161 ToeH2adD OE to A/D Driven 0.125 TCY – 5 — — ns
162 TadV2oeH Least Significant Data Valid Before OE
(data setup time
20 — — ns
162A TadV2oeH Most Significant Data Valid Before OE
(data setup time)
0.25 TCY + 20 — — ns
163 ToeH2adI OE to Data in Invalid (data Hold Time) 0 — — ns
166 TaIH2aIH ALE to ALE (cycle time) — TCY —ns
167 TACC Address Valid to Data Valid 0.5 TCY – 10 — — ns
168 Toe OE to Data Valid — — 0.125 TCY + 5 ns
170 TubH2oeH BA0 = 0 Valid Before OE 0.25 TCY ——ns
170A TubL2oeH BA0 = 1 Valid Before OE 0.5 TCY ——ns
Q1 Q2 Q3 Q4 Q1 Q2
OSC1
ALE
OE
Address Data
170
161
162
AD<7:0> Address
Address
A<19:8> Address
162A
BA0
Data
170A
151
150
166
167
155
153
163
154
168
CE
Note: Fmax = 25 MHz in 8-Bit External Memory mode.
2011 Microchip Technology Inc. DS39960C-page 507
PIC18F87K22 FAMILY
FIGURE 31-7: PROGRAM MEMO RY READ TIMING DIAGRAM
TABLE 31-11: CLKO AND I/O TIMING REQUIREMENTS
Param.
No Symbol Characteristics Min Typ Max Units
150 TadV2alL Address Out Valid to ALE
(address setup time)
0.25 TCY – 10 — — ns
151 TalL2adl ALE to Address Out Invalid
(address hold time)
5——ns
155 TalL2oeL ALE to OE 10 0.125 TCY —ns
160 TadZ2oeL AD High-Z to OE (bus release to OE)0——ns
161 ToeH2adD OE to AD Driven 0.125 TCY – 5 — — ns
162 TadV2oeH LS Data Valid before OE (data setup time) 20 — — ns
163 ToeH2adl OE to Data In Invalid (data hold time) 0 — — ns
164 TalH2alL ALE Pulse Width — 0.25 TCY —ns
165 ToeL2oeH OE Pulse Width 0.5 TCY – 5 0.5 TCY —ns
166 TalH2alH ALE to ALE (cycle time) — TCY —ns
167 Tacc Address Valid to Data Valid 0.75 TCY – 25 — — ns
168 Toe OE to Data Valid — 0.5 TCY – 25 ns
169 TalL2oeH ALE to OE 0.625 TCY – 10 — 0.625 TCY + 10 ns
171 TalH2csL Chip Enable Active to ALE 0.25 TCY – 20 — — ns
171A TubL2oeH AD Valid to Chip Enable Active — — 10 ns
Q1 Q2 Q3 Q4 Q1 Q2
OSC1
ALE
OE
Address Data from External
164
166
160
165
161
151 162
163
AD<15:0>
167
168
155
Address
Address
150
A<19:16> Address
169
BA0
CE
171
171A
Operating Conditions: 2.0V < VCC < 3.6V, -40°C < TA < +125°C unless otherwise stated.
PIC18F87K22 FAMILY
DS39960C-page 508 2011 Microchip Technology Inc.
FIGURE 31-8: P ROGRAM MEMORY WRITE TIMING DIAGRAM
TABLE 31-12: PROGRAM MEMORY WRITE TIMING REQUIREMENTS
Param.
No Symbol Characteristics Min Typ Max Units
150 TadV2alL Address Out Valid to ALE (address setup time) 0.25 TCY – 10 — — ns
151 TalL2adl ALE to Address Out Invalid (address hold time) 5 — — ns
153 TwrH2adl WRn to Data Out Invalid (data hold time) 5 — — ns
154 TwrL WRn Pulse Width 0.5 TCY – 5 0.5 TCY —ns
156 TadV2wrH Data Valid before WRn (data setup time) 0.5 TCY – 10 — — ns
157 TbsV2wrL Byte Select Valid before WRn
(byte select setup time)
0.25 T
CY ——ns
157A TwrH2bsI WRn to Byte Select Invalid (byte select hold time) 0.125 TCY – 5 — — ns
166 TalH2alH ALE to ALE (cycle time) — TCY —ns
171 TalH2csL Chip Enable Active to ALE 0.25 TCY – 20 — — ns
171A TubL2oeH AD Valid to Chip Enable Active — — 10 ns
Q1 Q2 Q3 Q4 Q1 Q2
OSC1
ALE
Address Data
156
150
151
153
AD<15:0> Address
WRH or
WRL
UB or
LB
157
154
157A
Address
A<19:16> Address
BA0
166
CE
171
171A
Operating Conditions: 2.0V < VCC < 3.6V, -40°C < TA < +125°C unless otherwise stated.
2011 Microchip Technology Inc. DS39960C-page 509
PIC18F87K22 FAMILY
FIGURE 31-9: RESET, WATCHDOG TIMER, OSCILLATOR START-UP TIMER AND
POWER-UP TIMER TIMING
FIGURE 31-10: BROWN-OUT RESET TIMING
VDD
MCLR
Internal
POR
PWRT
Time-out
Oscillator
Time-out
Internal
Reset
Watchdog
Timer
Reset
33
32
30
31
34
I/O Pins
34
Note: Refer to Figure 31-3 for load conditions.
VDD BVDD
35
VBGAP = 1.2V
VIRVST
Enable Internal
Internal Reference 36
Reference Voltage
Voltage Stable
PIC18F87K22 FAMILY
DS39960C-page 510 2011 Microchip Technology Inc.
TABLE 31-13: RESET, WATCHDOG TIMER, OSCILLATOR START-UP TIMER, POWER-UP TIMER
AND BROWN-OUT RESET REQUIREMENTS
Param.
No. Symbol Characteristic Min Typ Max Units Conditions
30 TmcL MCLR Pulse Width (low) 2 — — s
31 TWDT Watchdog Timer Time-out Period
(no postscaler)
—4.00— ms
32 TOST Oscillation Start-up Timer Period 1024 TOSC — 1024 TOSC —TOSC = OSC1 period
33 TPWRT Power-up Timer Period — 65.5 140 ms
34 TIOZ I/O High-Impedance from MCLR
Low or Watchdog Timer Reset
—2—s
35 TBOR Brown-out Reset Pulse Width 200 — — sVDD BVDD (see D005)
36 TIVRST Time for Internal Reference
Voltage to become Stable
—25— s
37 THLVD High/Low-Voltage Detect Pulse Width 200 — — sVDD VHLVD
38 TCSD CPU Start-up Time 5 — 10 s
39 TIOBST Time for INTOSC to Stabilize — 1 — ms
2011 Microchip Technology Inc. DS39960C-page 511
PIC18F87K22 FAMILY
FIGURE 31-11: HIGH/LOW-VOLTAGE DETECT CHARACTERISTICS
TABLE 31-14: HIGH/LOW-VOLTAGE DETECT CHARACTERISTICS
Standard Operating Conditions (unless otherwise stated)
Operating temperature -40°C TA +85°C for industrial
Param
No. Sym Characteristic Min Typ Max Units Conditions
D420 HLVD Voltage on VDD
Transition High-to-Low
HLVDL<3:0> = 0000 1.80 1.86 1.90 V
HLVDL<3:0> = 0001 2.03 2.12 2.13 V
HLVDL<3:0> = 0010 2.24 2.33 2.35 V
HLVDL<3:0> = 0011 2.40 2.49 2.53 V
HLVDL<3:0> = 0100 2.50 2.59 2.62 V
HLVDL<3:0> = 0101 2.70 2.75 2.84 V
HLVDL<3:0> = 0110 2.82 2.93 2.97 V
HLVDL<3:0> = 0111 2.95 3.07 3.10 V
HLVDL<3:0> = 1000 3.24 3.30 3.41 V
HLVDL<3:0> = 1001 3.42 3.48 3.59 V
HLVDL<3:0> = 1010 3.61 3.67 3.79 V
HLVDL<3:0> = 1011 3.82 3.87 4.01 V
HLVDL<3:0> = 1100 4.06 4.21 4.26 V
HLVDL<3:0> = 1101 4.33 4.42 4.55 V
HLVDL<3:0> = 1110 4.64 4.77 4.87 V
VHLVD
HLVDIF
VDD
(HLVDIF set by hardware) (HLVDIF can be
cleared in software)
VHLVD
For VDIRMAG = 1:
For VDIRMAG = 0:VDD
PIC18F87K22 FAMILY
DS39960C-page 512 2011 Microchip Technology Inc.
FIGURE 31-12: TIMER0 AND TIMER1 EXTERNAL CLOCK TIMINGS
TABLE 31-15: TIMER0 AND TIMER1 EXTERNAL CLOCK REQUIREMENTS
Param
No. Symbol Characteristic Min Max Units Conditions
40 TT0H T0CKI High Pulse Width No prescaler 0.5 TCY + 20 — ns
With prescaler 10 — ns
41 TT0L T0CKI Low Pulse Width No prescaler 0.5 TCY + 20 — ns
With prescaler 10 — ns
42 TT0P T0CKI Period No prescaler TCY + 10 — ns
With prescaler Greater of:
20 ns or
(T
CY + 40)/N
—nsN = prescale
value
(1, 2, 4,..., 256)
45 TT1H T1CKI High
Time
Synchronous, no prescaler 0.5 TCY + 20 — ns
Synchronous, with prescaler 10 — ns
Asynchronous 30 — ns
46 TT1L T1CKI Low
Time
Synchronous, no prescaler 0.5 TCY + 5 — ns
Synchronous, with prescaler 10 — ns
Asynchronous 30 — ns
47 TT1P T1CKI Input
Period
Synchronous Greater of:
20 ns or
(TCY + 40)/N
—nsN = prescale
value
(1, 2, 4, 8)
Asynchronous 60 — ns
FT1 T1CKI Oscillator Input Frequency Range DC 50 kHz
48 T
CKE2TMRI Delay from External T1CKI Clock Edge to
Timer Increment
2 TOSC 7 TOSC —
Note: Refer to Figure 31-3 for load conditions.
46
47
45
48
41
42
40
T0CKI
T1CKI
TMR0 or
TMR1
2011 Microchip Technology Inc. DS39960C-page 513
PIC18F87K22 FAMILY
FIGURE 31-13: CAPTURE/ COM PARE/PWM TIMINGS (ECCP1, ECCP2 MODULES)
TABLE 31-16: CAPTURE/COMPARE/PWM REQUIREMENTS (ECCP1, ECCP2 MODULES)
Param
No. Symbol Characteristic Min Max Units Conditions
50 TCCL CCPx Input Low
Time
No prescaler 0.5 TCY + 20 — ns
With prescaler 10 — ns
51 TCCH CCPx Input
High Time
No prescaler 0.5 TCY + 20 — ns
With prescaler 10 — ns
52 TCCP CCPx Input Period 3 TCY + 40
N
— ns N = prescale
value (1, 4 or 16)
53 TCCR CCPx Output Fall Time — 25 ns
54 TCCF CCPx Output Fall Time — 25 ns
Note: Refer to Figure 31-3 for load conditions.
CCPx
(Capture Mode)
50 51
52
CCPx
53 54
(Compare or PWM Mode)
PIC18F87K22 FAMILY
DS39960C-page 514 2011 Microchip Technology Inc.
FIGURE 31-14 : EXAMPLE SP I MASTER MODE TIMING (CKE = 0)
TABLE 31-17: EXAMPLE SPI MODE REQUIREMENTS (MASTER MODE, CKE = 0)
Param
No. Symbol Characteristic Min Max Units Conditions
73 TDIV2SCH,
TDIV2SCL
Setup Time of SDIx Data Input to SCKx Edge 20 — ns
73A TB2BLast Clock Edge of Byte 1 to the 1st Clock Edge
of Byte 2
1.5 TCY + 40 — ns
74 T
SCH2DIL,
T
SCL2DIL
Hold Time of SDIx Data Input to SCKx Edge 40 — ns
75 TDOR SDOx Data Output Rise Time — 25 ns
76 TDOF SDOx Data Output Fall Time — 25 ns
78 T
SCR SCKx Output Rise Time (Master mode) — 25 ns
79 T
SCF SCKx Output Fall Time (Master mode) — 25 ns
80 T
SCH2DOV,
T
SCL2DOV
SDOx Data Output Valid after SCKx Edge — 50 ns
SCKx
(CKPx = 0)
SCKx
(CKPx = 1)
SDOx
SDIx
73
74
75, 76
78
79
80
79
78
MSb LSb
bit 6 - - - - - - 1
LSb In
bit 6 - - - - 1
Note: Refer to Figure 31-3 for load conditions.
MSb In
2011 Microchip Technology Inc. DS39960C-page 515
PIC18F87K22 FAMILY
FIGURE 31-15 : EXAMPLE SP I MASTER MODE TIMING (CKE = 1)
TABLE 31-18: EXAMPLE SPI MODE REQUIREMENTS (MASTER MODE, CKE = 1)
Param.
No. Symbol Characteristic Min Max Units Conditions
73 TDIV2SCH,
TDIV2SCL
Setup Time of SDIx Data Input to SCKx Edge 20 — ns
73A TB2BLast Clock Edge of Byte 1 to the 1st Clock Edge
of Byte 2
1.5 TCY + 40 — ns
74 T
SCH2DIL,
T
SCL2DIL
Hold Time of SDIx Data Input to SCKx Edge 40 — ns
75 TDOR SDOx Data Output Rise Time — 25 ns
76 TDOF SDOx Data Output Fall Time — 25 ns
78 T
SCR SCKx Output Rise Time (Master mode) — 25 ns
79 T
SCF SCKx Output Fall Time (Master mode) — 25 ns
80 T
SCH2DOV,
T
SCL2DOV
SDOx Data Output Valid after SCKx Edge — 50 ns
81 TDOV2SCH,
TDOV2SCL
SDOx Data Output Setup to SCKx Edge T
CY —ns
SCKx
(CKPx = 0)
SCKx
(CKPx = 1)
SDOx
SDIx
81
74
75, 76
78
80
MSb
79
73
bit 6 - - - - - - 1
LSb In
bit 6 - - - - 1
LSb
Note: Refer to Figure 31-3 for load conditions.
MSb In
PIC18F87K22 FAMILY
DS39960C-page 516 2011 Microchip Technology Inc.
FIGURE 31-16 : EXAMPLE SP I SLAVE MODE TIMING (CKE = 0)
TABLE 31-19: EXAMPLE SPI MODE REQUIREMENTS (SLAVE MODE TIMING, CKE = 0)
Param
No. Symbol Characteristic Min Max Units Conditions
70 TSSL2SCH,
T
SSL2SCL
SSx to SCKx or SCKx Input 3 TCY —ns
70A T
SSL2WB SSx to write to SSPBUF 3 TCY —ns
71 T
SCH SCKx Input High Time
(Slave mode)
Continuous 1.25 TCY + 30 — ns
71A Single Byte 40 — ns (Note 1)
72 TSCL SCKx Input Low Time
(Slave mode)
Continuous 1.25 TCY + 30 — ns
72A Single Byte 40 — ns (Note 1)
73 TDIV2SCH,
TDIV2SCL
Setup Time of SDIx Data Input to SCKx Edge 20 — ns
73A TB2BLast Clock Edge of Byte 1 to the First Clock Edge of Byte 2 1.5 TCY + 40 — ns (Note 2)
74 TSCH2DIL,
T
SCL2DIL
Hold Time of SDIx Data Input to SCKx Edge 40 — ns
75 TDOR SDOx Data Output Rise Time — 25 ns
76 TDOF SDOx Data Output Fall Time — 25 ns
77 T
SSH2DOZ SSx to SDOx Output High-impedance 10 50 ns
78 T
SCR SCKx Output Rise Time (Master mode) — 25 ns
79 T
SCF SCKx Output Fall Time (Master mode) — 25 ns
80 T
SCH2DOV,
T
SCL2DOV
SDOx Data Output Valid after SCKx Edge — 50 ns
83 T
SCH2SSH,
T
SCL2SSH
SSx after SCKx Edge 1.5 TCY + 40 — ns
Note 1: Requires the use of Parameter #73A.
2: Only if Parameter #71A and #72A are used.
SSx
SCKx
(CKPx = 0)
SCKx
(CKP = 1)
SDOx
SDIx
70
71 72
73
74
75, 76 77
78
79
80
79
78
MSb LSb
bit 6 - - - - - - 1
bit 6 - - - - 1 LSb In
83
Note: Refer to Figure 31-3 for load conditions.
MSb In
2011 Microchip Technology Inc. DS39960C-page 517
PIC18F87K22 FAMILY
FIGURE 31-17 : EXAMPLE SP I SLAVE MODE TIMING (CKE = 1)
TABLE 31-20: EXAMPLE SPI SLAVE MODE REQUIREMENTS (CKE = 1)
Param
No. Symbol Characteristic Min Max Units Conditions
70 TSSL2SCH,
T
SSL2SCL
SSx to SCKx or SCKx Input 3 TCY —ns
70A T
SSL2WB SSx to write to SSPBUF 3 TCY —ns
71 T
SCH SCKx Input High Time
(Slave mode)
Continuous 1.25 TCY + 30 — ns
71A Single Byte 40 — ns (Note 1)
72 TSCL SCKx Input Low Time
(Slave mode)
Continuous 1.25 TCY + 30 — ns
72A Single Byte 40 — ns (Note 1)
73A TB2BLast Clock Edge of Byte 1 to the First Clock Edge of Byte 2 1.5 TCY + 40 — ns (Note 2)
74 TSCH2DIL,
T
SCL2DIL
Hold Time of SDIx Data Input to SCKx Edge 40 — ns
75 TDOR SDOx Data Output Rise Time — 25 ns
76 TDOF SDOx Data Output Fall Time — 25 ns
77 T
SSH2DOZ SSx to SDOx Output High-Impedance 10 50 ns
78 T
SCR SCKx Output Rise Time (Master mode) — 25 ns
79 T
SCF SCKx Output Fall Time (Master mode) — 25 ns
80 T
SCH2DOV,
T
SCL2DOV
SDOx Data Output Valid after SCKx Edge — 50 ns
82 T
SSL2DOV SDOx Data Output Valid after SSx Edge — 50 ns
83 T
SCH2SSH,
T
SCL2SSH
SSx after SCKx Edge 1.5 TCY + 40 — ns
Note 1: Requires the use of Parameter #73A.
2: Only if Parameter #71A and #72A are used.
SSx
SCKx
(CKPx = 0)
SCKx
(CKPx = 1)
SDOx
SDIx
70
71 72
82
74
75, 76
MSb bit 6 - - - - - - 1 LSb
77
bit 6 - - - - 1 LSb In
80
83
Note: Refer to Figure 31-3 for load conditions.
MSb In
PIC18F87K22 FAMILY
DS39960C-page 518 2011 Microchip Technology Inc.
FIGURE 31-18 : I 2C™ BUS START/STOP BITS TIMING
TABLE 31-21: I2C™ BUS START/STOP BITS REQUIREMENTS (SLAVE MODE)
Param.
No. Symbol Characteristic Min Max Units Conditions
90 TSU:STA Start Condition 100 kHz mode 4700 — ns Only relevant for Repeated
Start condition
Setup Time 400 kHz mode 600 —
91 THD:STA Start Condition 100 kHz mode 4000 — ns After this period, the first
clock pulse is generated
Hold Time 400 kHz mode 600 —
92 TSU:STO Stop Condition 100 kHz mode 4700 — ns
Setup Time 400 kHz mode 600 —
93 THD:STO Stop Condition 100 kHz mode 4000 — ns
Hold Time 400 kHz mode 600 —
Note: Refer to Figure 31-3 for load conditions.
91
92
93
SCLx
SDAx
Start
Condition
Stop
Condition
90
2011 Microchip Technology Inc. DS39960C-page 519
PIC18F87K22 FAMILY
FIGURE 31-19 : I 2C™ BUS DATA TIMING
TABLE 31-22: I2C™ BUS DATA REQUIREMENTS (SLAVE MODE)
Param.
No. Symbol Characteristic Min Max Units Conditions
100 THIGH Clock High Time 100 kHz mode 4.0 — s
400 kHz mode 0.6 — s
MSSP module 1.5 TCY —
101 TLOW Clock Low Time 100 kHz mode 4.7 — s
400 kHz mode 1.3 — s
MSSP module 1.5 TCY —
102 TRSDAx and SCLx Rise Time 100 kHz mode — 1000 ns
400 kHz mode 20 + 0.1 CB300 ns CB is specified to be from
10 to 400 pF
103 TFSDAx and SCLx Fall Time 100 kHz mode — 300 ns
400 kHz mode 20 + 0.1 CB300 ns CB is specified to be from
10 to 400 pF
90 TSU:STA Start Condition Setup Time 100 kHz mode 4.7 — s Only relevant for Repeated
Start condition
400 kHz mode 0.6 — s
91 THD:STA Start Condition Hold Time 100 kHz mode 4.0 — s After this period, the first clock
pulse is generated
400 kHz mode 0.6 — s
106 THD:DAT Data Input Hold Time 100 kHz mode 0 — ns
400 kHz mode 0 0.9 s
107 TSU:DAT Data Input Setup Time 100 kHz mode 250 — ns (Note 2)
400 kHz mode 100 — ns
92 TSU:STO Stop Condition Setup Time 100 kHz mode 4.7 — s
400 kHz mode 0.6 — s
109 TAA Output Valid from Clock 100 kHz mode — 3500 ns (Note 1)
400 kHz mode — — ns
110 TBUF Bus Free Time 100 kHz mode 4.7 — s Time the bus must be free before
a new transmission can start
400 kHz mode 1.3 — s
D102 CBBus Capacitive Loading — 400 pF
Note 1: As a transmitter, the device must provide this internal minimum delay time to bridge the undefined region (min. 300 ns) of
the falling edge of SCLx to avoid unintended generation of Start or Stop conditions.
2: A Fast mode I2C™ bus device can be used in a Standard mode I2C bus system, but the requirement, TSU:DAT 250 ns,
must then be met. This will automatically be the case if the device does not stretch the LOW period of the SCLx signal. If
such a device does stretch the LOW period of the SCLx signal, it must output the next data bit to the SDAx line,
TR max. + TSU:DAT = 1000 + 250 = 1250 ns (according to the Standard mode I2C bus specification), before the SCLx line
is released.
Note: Refer to Figure 31-3 for load conditions.
90
91 92
100
101
103
106 107
109 109
110
102
SCLx
SDAx
In
SDAx
Out
PIC18F87K22 FAMILY
DS39960C-page 520 2011 Microchip Technology Inc.
FIGURE 31-20 : MS SP I2C™ BUS START/STOP BITS TIMING WAVEFORMS
TABLE 31-23: MSSP I2C™ BUS START/STOP BITS REQUIREMENTS
FIGURE 31-21 : MS SP I2C™ BUS DATA TIMING
Param.
No. Symbol Characteristic Min Max Units Conditions
90 TSU:STA Start Condition 100 kHz mode 2(TOSC)(BRG + 1) — ns Only relevant for
Repeated Start
condition
Setup Time 400 kHz mode 2(TOSC)(BRG + 1) —
1 MHz mode(1) 2(TOSC)(BRG + 1) —
91 THD:STA Start Condition 100 kHz mode 2(TOSC)(BRG + 1) — ns After this period, the
first clock pulse is
generated
Hold Time 400 kHz mode 2(TOSC)(BRG + 1) —
1 MHz mode(1) 2(TOSC)(BRG + 1) —
92 TSU:STO Stop Condition 100 kHz mode 2(TOSC)(BRG + 1) — ns
Setup Time 400 kHz mode 2(TOSC)(BRG + 1) —
1 MHz mode(1) 2(TOSC)(BRG + 1) —
93 THD:STO Stop Condition 100 kHz mode 2(TOSC)(BRG + 1) — ns
Hold Time 400 kHz mode 2(TOSC)(BRG + 1) —
1 MHz mode(1) 2(TOSC)(BRG + 1) —
Note 1: Maximum pin capacitance = 10 pF for all I2C™ pins.
Note: Refer to Figure 31-3 for load conditions.
91 93
SCLx
SDAx
Start
Condition
Stop
Condition
90 92
Note: Refer to Figure 31-3 for load conditions.
90 91 92
100
101
103
106 107
109 109 110
102
SCLx
SDAx
In
SDAx
Out
2011 Microchip Technology Inc. DS39960C-page 521
PIC18F87K22 FAMILY
TABLE 31-24: MSSP I2C™ BUS DATA REQUIREMENTS
Param.
No. Symbol Characteristic Min Max Units Conditions
100 THIGH Clock High
Time
100 kHz mode 2(TOSC)(BRG + 1) — —
400 kHz mode 2(T
OSC)(BRG + 1) — —
1 MHz mode(1) 2(TOSC)(BRG + 1) — —
101 TLOW Clock Low Time 100 kHz mode 2(TOSC)(BRG + 1) — —
400 kHz mode 2(T
OSC)(BRG + 1) — —
1 MHz mode(1) 2(TOSC)(BRG + 1) — —
102 TRSDAx and
SCLx Rise
Time
100 kHz mode — 1000 ns CB is specified to be from
10 to 400 pF
400 kHz mode 20 + 0.1 CB300 ns
1 MHz mode(1) — 300 ns
103 TFSDAx and
SCLx Fall Time
100 kHz mode — 300 ns CB is specified to be from
10 to 400 pF
400 kHz mode 20 + 0.1 CB 300 ns
1 MHz mode(1) — 100 ns
90 T
SU:STA Start Condition
Setup Time
100 kHz mode 2(TOSC)(BRG + 1) — — Only relevant for Repeated
Start condition
400 kHz mode 2(T
OSC)(BRG + 1) — —
1 MHz mode(1) 2(TOSC)(BRG + 1) — —
91 THD:STA Start Condition
Hold Time
100 kHz mode 2(TOSC)(BRG + 1) — — After this period, the first
clock pulse is generated
400 kHz mode 2(T
OSC)(BRG + 1) — —
1 MHz mode(1) 2(TOSC)(BRG + 1) — —
106 THD:DAT Data Input
Hold Time
100 kHz mode 0 — ns
400 kHz mode 0 0.9 s
1 MHz mode(1) ——ns
107 T
SU:DAT Data Input
Setup Time
100 kHz mode 250 — ns (Note 2)
400 kHz mode 100 — ns
1 MHz mode(1) ——ns
92 T
SU:STO Stop Condition
Setup Time
100 kHz mode 2(TOSC)(BRG + 1) — —
400 kHz mode 2(T
OSC)(BRG + 1) — —
1 MHz mode(1) 2(TOSC)(BRG + 1) — —
109 T
AA Output Valid
from Clock
100 kHz mode — 3500 ns
400 kHz mode — 1000 ns
1 MHz mode(1) ——ns
110 TBUF Bus Free Time 100 kHz mode 4.7 — s Time the bus must be free
before a new transmission
can start
400 kHz mode 1.3 — s
1 MHz mode(1) ——s
D102 CBBus Capacitive Loading — 400 pF
Note 1: Maximum pin capacitance = 10 pF for all I2C™ pins.
2: A Fast mode I2C bus device can be used in a Standard mode I2C bus system, but Parameter
#107 250 ns must then be met. This will automatically be the case if the device does not stretch the LOW
period of the SCLx signal. If such a device does stretch the LOW period of the SCLx signal, it must output
the next data bit to the SDAx line, Parameter #102 + Parameter #107 = 1000 + 250 = 1250 ns (for 100 kHz
mode), before the SCLx line is released.
PIC18F87K22 FAMILY
DS39960C-page 522 2011 Microchip Technology Inc.
FIGURE 31-22: EUSART SYNCHRONO US TRANSMISSION (MASTER/SLAVE) TIMING
TABLE 31-25: EUSART/AUSART SYNCHRONOUS TRANSMISSION REQUIREMENTS
FIGURE 31-23: EUSART/A USART SYNCHRONOUS RECEIVE (MASTER/SLAVE) TIMING
TABLE 31-26: EUSART/AUSART SYNCHRONOUS RECEIVE REQUIREMENTS
Param
No. Symbol Characteristic Min Max Units Conditions
120 TCKH2DTV SYNC XMIT (MASTER and SLAVE)
Clock High to Data Out Valid — 40 ns
121 TCKRF Clock Out Rise Time and Fall Time (Master mode) — 20 ns
122 TDTRF Data Out Rise Time and Fall Time — 20 ns
Param.
No. Symbol Characteristic Min Max Units Conditions
125 TDTV2CKL SYNC RCV (MASTER and SLAVE)
Data Hold before CKx (DTx hold time) 10 — ns
126 TCKL2DTL Data Hold after CKx (DTx hold time) 15 — ns
121 121
120 122
TXx/CKx
RXx/DTx
pin
pin
Note: Refer to Figure 31-3 for load conditions.
125
126
TXx/CKx
RXx/DTx
pin
pin
Note: Refer to Figure 31-3 for load conditions.
2011 Microchip Technology Inc. DS39960C-page 523
PIC18F87K22 FAMILY
TABLE 31-27: A/D CONVERTER CHARACTERISTICS: PIC18F87K22 FAMILY (INDUSTRIAL)
Param
No. Sym Characteristic Min Typ Max Units Conditions
A01 NRResolution — — 12 bit VREF 3.0V
A03 EIL Integral Linearity Error — <±1 ±2.0 LSB VDD = 3.0V (VREF 3.0V)
——±2.0LSBV
DD = 5.0V
A04 EDL Differential Linearity Error — <±1 +1.5/-1.0 LSB VDD = 3.0V (VREF 3.0V)
——+1.5/-1.0LSBV
DD = 5.0V
A06 EOFF Offset Error — <±1 ±5 LSB VDD = 3.0V (VREF 3.0V)
——±3LSBV
DD = 5.0V
A07 EGN Gain Error — <±1 ±1.25 LSB VDD = 3.0V (VREF 3.0V)
——±2.00LSBV
DD = 5.0V
A10 — Monotonicity Guaranteed(1) —VSS VAIN VREF
A20 VREF Reference Voltage Range
(VREFH – VREFL)
3—V
DD – VSS V For 12-bit resolution
A21 VREFH Reference Voltage High VSS + 3.0V — VDD + 0.3V V For 12-bit resolution
A22 VREFL Reference Voltage Low VSS – 0.3V — VDD – 3.0V V For 12-bit resolution
A25 VAIN Analog Input Voltage VREFL —VREFH V
A30 ZAIN Recommended
Impedance of Analog
Voltage Source
——2.5k
A50 IREF VREF Input Current(2) —
—
—
—
5
150
A
A
During VAIN acquisition.
During A/D conversion cycle.
Note 1: The A/D conversion result never decreases with an increase in the input voltage and has no missing codes.
2: VREFH current is from the RA3/AN3/VREF+ pin or VDD, whichever is selected as the VREFH source. VREFL current is from
the RA2/AN2/VREF-/CVREF pin or VSS, whichever is selected as the VREFL source.
PIC18F87K22 FAMILY
DS39960C-page 524 2011 Microchip Technology Inc.
FIGURE 31-24: A/D CONVERSION TIMING
TABLE 31-28: A/D CONVERSION REQUIREMENTS
Param
No. Symbol Characteristic Min Max Units Conditions
130 TAD A/D Clock Period 0.8 12.5(1) µs TOSC based, VREF 3.0V
1.4 25(1) µs VDD = 3.0V; TOSC based,
VREF full range
—1µs A/D RC mode
—3µsV
DD = 3.0V; A/D RC mode
131 TCNV Conversion Time
(not including acquisition time)(2) 14 15 TAD
132 TACQ Acquisition Time(3) 1.4 — µs -40°C to +85°C
135 TSWC Switching Time from Convert Sample — (Note 4)
137 TDIS Discharge Time 0.2 — s -40°C to +85°C
Note 1: The time of the A/D clock period is dependent on the device frequency and the TAD clock divider.
2: ADRES registers may be read on the following TCY cycle.
3: The time for the holding capacitor to acquire the “New” input voltage when the voltage changes full scale
after the conversion (VDD to VSS or VSS to VDD). The source impedance (RS) on the input channels is 50.
4: On the following cycle of the device clock.
131
130
132
BSF ADCON0, GO
Q4
A/D CLK
A/D DATA
ADRES
ADIF
GO
SAMPLE
OLD_DATA
SAMPLING STOPPED
DONE
NEW_DATA
(Note 2)
11 10 9 2 1 0
Note 1: If the A/D clock source is selected as RC, a time of TCY is added before the A/D clock starts. This allows the SLEEP instruction to
be executed.
2: This is a minimal RC delay (typically 100 ns), which also disconnects the holding capacitor from the analog input.
. . . . . .
TCY (Note 1)
2011 Microchip Technology Inc. DS39960C-page 525
PIC18F87K22 FAMILY
32.0 PACKAGING INFORMATION
32.1 Package Marking Informat ion
3
e
3
e
64-Lead TQFP
XXXXXXXXXX
XXXXXXXXXX
XXXXXXXXXX
YYWWNNN
Example
18F67K22
-I/PT
1110017
80-Lead TQFP
XXXXXXXXXXXX
XXXXXXXXXXXX
YYWWNNN
Example
PIC18F87K22
-I/PT
1110017
Legend: XX...X Customer-specific information
Y Year code (last digit of calendar year)
YY Year code (last 2 digits of calendar year)
WW Week code (week of January 1 is week ‘01’)
NNN Alphanumeric traceability code
Pb-free JEDEC designator for Matte Tin (Sn)
*This package is Pb-free. The Pb-free JEDEC designator ( )
can be found on the outer packaging for this package.
Note: In the event the full Microchip part number cannot be marked on one line, it will
be carried over to the next line, thus limiting the number of available
characters for customer-specific information.
3
e
3
e
3
e
64-Lead QFN
XXXXXXXXXX
XXXXXXXXXX
XXXXXXXXXX
YYWWNNN
Example
18F67K22
-I/MR
1110017
PIC18F87K22 FAMILY
DS39960C-page 526 2011 Microchip Technology Inc.
32.2 Package Details
The following sections give the technical details of the
packages.
Note: For the most current package drawings, please see the Microchip Packaging Specification located at
http://www.microchip.com/packaging
2011 Microchip Technology Inc. DS39960C-page 527
PIC18F87K22 FAMILY
Note: For the most current package drawings, please see the Microchip Packaging Specification located at
http://www.microchip.com/packaging
PIC18F87K22 FAMILY
DS39960C-page 528 2011 Microchip Technology Inc.
Note: For the most current package drawings, please see the Microchip Packaging Specification located at
http://www.microchip.com/packaging
2011 Microchip Technology Inc. DS39960C-page 529
PIC18F87K22 FAMILY
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E1
e
bN
NOTE 1 123 NOTE 2
A
A2
L1
A1
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c
α
βφ
+ ,2
PIC18F87K22 FAMILY
DS39960C-page 530 2011 Microchip Technology Inc.
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2011 Microchip Technology Inc. DS39960C-page 531
PIC18F87K22 FAMILY
APPENDIX A: REVISION HISTORY
Revision A (November 2009)
Original data sheet for PIC18F87K22 family devices.
Revision B (May 2010)
Minor edits to text throughout document. Replaced all
TBDs with the correct value.
Revision C (March 2011)
Section 2.4 “Voltage Regulato r Pins (ENVREG an d
VCAP/VDDCORE)” has been replaced with a new and
more detailed description and the 80-pin TQFP
diagrams have been updated. Minor text edits
throughout document.
PIC18F87K22 FAMILY
DS39960C-page 532 2011 Microchip Technology Inc.
APPENDIX B: MIGRATION FROM
PIC18F87J11 AND
PIC18F8722 TO
PIC18F87K22
Devices in the PIC18F87K22, PIC18F87J11 and
PIC18F8722 families are similar in their functions and
features. Code can be migrated from the other families
to the PIC18F87K22 without many changes. The differ-
ences between the device families are listed in
Table B-1.
TABLE B-1: NOTABLE DIFFERENCES BETWEEN PIC18F87K22, PIC18F87J11 AND PIC18F8722
FAMILIES
Characteristic PIC18F87K22 Family 18F87J11 Family PIC18F8722 Family
Max Operating Frequency 64 MHz 48 MHz 40 MHz
Max Program Memory 128 Kbytes 128 Kbytes 128 Kbytes
Data Memory 3,862 bytes 3,930 bytes 3,930 bytes
Program Memory
Endurance
10,000 Write/Erase (minimum) 10,000 Write/Erase (minimum) 10,000 Write/Erase (minimum)
Single Word Write for Flash No Yes No
Oscillator Options PLL can be used with INTOSC PLL can be used with INTOSC PLL can be used with INTOSC
CTMU Yes No No
RTCC Yes No No
SOSC Oscillator Options
TICKI Clock
Low-Power Oscillator Option for
SOSC
T1CKI can be used as a Clock
without Enabling the SOSC
Oscillator
No No
INTOSC Up to 16 MHz Up to 8 MHz Up to 8 MHz
SPI/I2C™ 2 2 2
Timers 11 5 5
ECCP 3 3
CCP 7 2 2
Data EEPROM Yes No Yes
Programmable BOR Multiple Level BOR One Level BOR Multiple Level BOR
WDT Prescale Options 22 16 16
5V Operation Yes No (3.3V) Yes
nanoWatt XLP Yes No No
Regulator Yes Yes No
Low-Power BOR Yes No No
A/D Converter 12-Bit Resolution, 24 Input
Channels, Differential
10-Bit Resolution, 15 Input
Channels, Non-Differential
10-Bit Resolution, 16 Input
Channels, Non-Differential
Internal Temp Sensor Yes No No
Programmable HLVD Yes No Yes
EUSART 2 EUSART 2 EUSART 2 EUSART
Comparators 3 2 2
Oscillator options 14 Options by FOSC<3:0> 8 Options by FOSC<3:0> 12 Options by FOSC<3:0>
Ultra-Low-Power Wake-up
(ULPW)
Yes No No
Power-up Timer Yes Yes Yes
MCLR Pin as Input Port Yes No Yes
2011 Microchip Technology Inc. DS39960C-page 533
PIC18F87K22 FAMILY
INDEX
A
A/D .................................................................................... 351
Acquisition Requirements ......................................... 361
Analog Port Pins, Configuring................................... 362
Associated Registers ................................................ 365
Automatic Acquisition Time, Selecting
and Configuring ................................................ 362
Configuring the Module............................................. 360
Conversion Clock (TAD) ............................................ 362
Conversion Requirements ........................................ 524
Conversion Status (GO/DONE Bit)........................... 358
Conversions .............................................................. 363
Converter Characteristics ......................................... 523
Converter Interrupt, Configuring ............................... 360
Operation in Power-Managed Modes ....................... 364
Use of the Special Event Triggers ............................ 364
Absolute Maximum Ratings .............................................. 485
AC (Timing) Characteristics .............................................. 501
Load Conditions for Device
Timing Specifications........................................ 502
Parameter Symbology .............................................. 501
Temperature and Voltage Specifications .................. 502
Timing Conditions ..................................................... 502
ACKSTAT ......................................................................... 317
ACKSTAT Status Flag ...................................................... 317
ADCON0 Register
GO/DONE Bit............................................................ 358
ADDFSR ........................................................................... 474
ADDLW ............................................................................. 437
ADDULNK......................................................................... 474
ADDWF............................................................................. 437
ADDWFC .......................................................................... 438
Analog-to-Digital Converter. See A/D.
ANDLW ............................................................................. 438
ANDWF............................................................................. 439
Assembler
MPASM Assembler................................................... 482
Auto-Wake-up on Sync Break Character.......................... 342
B
Baud Rate Generator........................................................ 313
BC ..................................................................................... 439
BCF................................................................................... 440
BF ..................................................................................... 317
BF Status Flag .................................................................. 317
Block Diagrams
16-Bit Byte Select Mode ........................................... 127
16-Bit Byte Write Mode............................................. 125
16-Bit Word Write Mode............................................ 126
8-Bit Multiplexed Mode Example .............................. 129
A/D ............................................................................ 359
A/D Result Justification............................................. 355
Analog Input Model ................................................... 360
Baud Rate Generator................................................ 313
Capture Mode Operation .................................. 251, 263
Comparator Analog Input Model ............................... 370
Comparator Configurations....................................... 372
Comparator Simplified .............................................. 367
Comparator Voltage Reference ................................ 376
Comparator Voltage Reference Output
Buffer Example ................................................. 377
Compare Mode Operation ................................ 253, 264
Connections for On-Chip Voltage Regulator............. 421
Crystal/Ceramic Resonator Operation
(HS or HSPLL).................................................... 50
CTMU ....................................................................... 385
CTMU Current Source Calibration Circuit ................ 391
CTMU Typical Connections and Internal
Configuration for Pulse Delay Generation........ 399
CTMU Typical Connections and Internal
Configuration for Time Measurement ............... 398
Device Clock............................................................... 44
Enhanced PWM Mode.............................................. 265
EUSART Receive ..................................................... 340
EUSART Transmit.................................................... 337
External Clock Input Operation (EC) .......................... 51
External Clock Input Operation (HS) .......................... 51
External Components for SOSC Low-Power
Oscillator........................................................... 201
External Power-on Reset Circuit
(Slow VDD Power-up) ......................................... 75
Fail-Safe Clock Monitor (FSCM)............................... 424
Full-Bridge Application Example............................... 269
Generic I/O Port Operation....................................... 165
Half-Bridge Applications ........................................... 275
High/Low-Voltage Detect with External Input ........... 380
Interrupt Logic........................................................... 142
INTIO1 Oscillator Mode.............................................. 52
INTIO2 Oscillator Mode.............................................. 52
MSSP (SPI Mode) .................................................... 281
MSSPx (I2C Master Mode) ....................................... 311
MSSPx (I2C Mode) ................................................... 291
On-Chip Reset Circuit................................................. 73
PIC18F6XK22............................................................. 13
PIC18F8XK22............................................................. 14
PLL ............................................................................. 51
PORTD and PORTE (Parallel Slave Port)................ 189
PWM Operation (Simplified) ..................................... 255
RC Oscillator Mode .................................................... 49
RCIO Oscillator Mode................................................. 49
Reads from Flash Program Memory ........................ 115
RTCC........................................................................ 227
RTCC Clock Source Multiplexing ............................. 238
Simplified Steering.................................................... 278
Single Comparator.................................................... 370
SPI Master/Slave Connection................................... 285
Table Read Operation .............................................. 111
Table Write Operation .............................................. 112
Table Writes to Flash Program Memory ................... 117
Timer0 in 16-Bit Mode .............................................. 194
Timer0 in 8-Bit Mode ................................................ 194
Timer1 ...................................................................... 200
Timer2 ...................................................................... 210
Timer3/5/7 ................................................................ 215
Timer4 ...................................................................... 224
Ultra Low-Power Wake-up Initialization...................... 70
Using Open-Drain Output (USART) ......................... 167
Watchdog Timer ....................................................... 419
BN..................................................................................... 440
BNC .................................................................................. 441
BNN .................................................................................. 441
BNOV ............................................................................... 442
BNZ .................................................................................. 442
BOR. See Brown-out Reset.
BOV .................................................................................. 445
BRA .................................................................................. 443
PIC18F87K22 FAMILY
DS39960C-page 534 2011 Microchip Technology Inc.
Break Character (12-Bit) Transmit and Receive ............... 344
BRG. See Baud Rate Generator.
Brown-out Reset (BOR) ...................................................... 75
Detecting..................................................................... 75
BSF ................................................................................... 443
BTFSC .............................................................................. 444
BTFSS............................................................................... 444
BTG................................................................................... 445
BZ...................................................................................... 446
C
C Compilers
MPLAB C18 ..............................................................482
CALL ................................................................................. 446
CALLW.............................................................................. 475
Capture (CCP Module)...................................................... 250
CCPR4H:CCPR4L Registers.................................... 250
Pin Configuration ...................................................... 250
Prescaler................................................................... 251
Software Interrupt ..................................................... 251
Timer1/3/5/7 Mode Selection .................................... 250
Capture (ECCP Module) ................................................... 263
CCPRxH:CCPRxL Registers .................................... 263
ECCP Pin Configuration ........................................... 263
Prescaler................................................................... 263
Software Interrupt ..................................................... 263
Timer1/2/3/4/6/8/10/12 Mode Selection .................... 263
Capture, Compare, Timer1/3/5/7
Associated Registers ................................................ 253
Capture/Compare/PWM (CCP)......................................... 245
Capture Mode. See Capture.
CCP Mode and Timer Resources ............................. 249
CCP6/7/8/9 Pin Assignment ..................................... 250
CCPRxH Register ..................................................... 249
CCPRxL Register......................................................249
Compare Mode. See Compare.
Configuration............................................................. 249
Open-Drain Output Option ........................................ 250
Charge Time Measurement Unit (CTMU) .........................385
Associated Registers ................................................ 401
Calibrating the Module .............................................. 390
Creating a Delay ....................................................... 399
Effects of a Reset......................................................401
Measuring Capacitance with the CTMU ................... 396
Measuring Temperature............................................ 400
Measuring Time ........................................................ 398
Module Initialization .................................................. 390
Operation .................................................................. 389
During Sleep and Idle Modes............................ 401
Clock Sources ..................................................................... 48
Default System Clock on Reset .................................. 49
Selection ..................................................................... 48
CLRF................................................................................. 447
CLRWDT........................................................................... 447
Code Examples
16 x 16 Signed Multiply Routine ............................... 140
16 x 16 Unsigned Multiply Routine ........................... 140
8 x 8 Signed Multiply Routine ................................... 139
8 x 8 Unsigned Multiply Routine ............................... 139
Capacitance Calibration Routine .............................. 395
Changing Between Capture Prescalers ............ 251, 263
Computed GOTO Using an Offset Value.................... 91
Current Calibration Routine ...................................... 393
Data EEPROM Read ................................................ 136
Data EEPROM Refresh Routine............................... 137
Data EEPROM Write ................................................ 136
Erasing a Flash Program Memory Row.................... 116
Fast Register Stack .................................................... 91
How to Clear RAM (Bank 1) Using Indirect
Addressing........................................................ 105
Initializing PORTA..................................................... 170
Initializing PORTB..................................................... 172
Initializing PORTC .................................................... 174
Initializing PORTD .................................................... 176
Initializing PORTE..................................................... 178
Initializing PORTF..................................................... 181
Initializing PORTG .................................................... 183
Initializing PORTH .................................................... 185
Initializing PORTJ ..................................................... 187
Loading the SSP1BUF (SSP1SR) Register.............. 284
Reading a Flash Program Memory Word ................. 115
Routine for Capacitive Touch Switch........................ 397
Routine for Temperature Measurement
Using Internal Diode ......................................... 400
Saving STATUS, WREG and BSR
Registers in RAM.............................................. 163
Setting the RTCWREN Bit........................................ 239
Setup for CTMU Calibration Routines ...................... 392
Ultra Low-Power Wake-up Initialization ...................... 70
Writing to Flash Program Memory.................... 119–120
Code Protection ................................................................ 403
COMF ............................................................................... 448
Comparator....................................................................... 367
Analog Input Connection Considerations ................. 370
Associated Registers................................................ 374
Configuration and Control......................................... 371
Effects of a Reset ..................................................... 374
Enable and Input Selection....................................... 371
Enable and Output Selection.................................... 371
Interrupts .................................................................. 373
Operation.................................................................. 370
Operation During Sleep ............................................ 374
Response Time......................................................... 370
Comparator Specifications................................................ 500
Comparator Voltage Reference ........................................ 375
Accuracy and Error................................................... 376
Associated Registers................................................ 377
Configuring ............................................................... 375
Connection Considerations....................................... 376
Effects of a Reset ..................................................... 376
Operation During Sleep ............................................ 376
Compare (CCP Module) ................................................... 252
CCP Pin Configuration.............................................. 252
CCPR4 Register ....................................................... 252
Software Interrupt ..................................................... 252
Special Event Trigger ............................................... 252
Timer1/3/5/7 Mode Selection.................................... 252
Compare (ECCP Module)................................................. 264
CCPRx Register ....................................................... 264
Pin Configuration ...................................................... 264
Software Interrupt ..................................................... 264
Special Event Trigger ....................................... 221, 264
Timer1/2/3/4/6/8/10/12 Mode Selection.................... 264
Computed GOTO................................................................ 91
Configuration Bits ............................................................. 403
Configuration Mismatch (CM) Reset................................... 76
Configuration Register Protection..................................... 429
2011 Microchip Technology Inc. DS39960C-page 535
PIC18F87K22 FAMILY
Core Features
Easy Migration ............................................................ 10
Extended Instruction Set............................................... 9
External Memory Bus.................................................... 9
Memory Options............................................................ 9
nanoWatt Technology ................................................... 9
Oscillator Options and Features ................................... 9
CPFSEQ ........................................................................... 448
CPFSGT ........................................................................... 449
CPFSLT ............................................................................ 449
Crystal Oscillator/Ceramic Resonator ................................. 50
Customer Change Notification Service ............................. 544
Customer Notification Service........................................... 544
Customer Support ............................................................. 544
D
Data Addressing Modes.................................................... 105
Comparing Addressing Modes with
the Extended Instruction Set Enabled .............. 109
Direct......................................................................... 105
Indexed Literal Offset................................................ 108
BSR .................................................................. 110
Instructions Affected ......................................... 108
Mapping Access Bank ...................................... 110
Indirect ...................................................................... 105
Inherent and Literal ................................................... 105
Data EEPROM
Code Protection ........................................................ 429
Data EEPROM Memory
Associated Registers ................................................ 138
EEADR and EEADRH Registers .............................. 133
EECON1 and EECON2 Registers ............................ 133
Operation During Code-Protect ................................ 137
Overview ................................................................... 133
Reading..................................................................... 135
Spurious Write Protection ......................................... 137
Using......................................................................... 137
Write Verify ............................................................... 135
Writing....................................................................... 135
Data Memory ...................................................................... 94
Access Bank ............................................................... 96
Bank Select Register (BSR)........................................ 94
Extended Instruction Set........................................... 108
General Purpose Registers......................................... 96
Memory Maps
PIC18FX5K22/X7KJ22 Devices ......................... 95
Special Function Registers ................................. 97
Special Function Registers (SFRs)............................. 97
DAW.................................................................................. 450
DC Characteristics
CTMU Current Source .............................................. 498
PIC18F87K22 Family (Industrial).............................. 497
Power-Down and Supply Current ............................. 488
Supply Voltage.......................................................... 487
DCFSNZ ........................................................................... 451
DECF ................................................................................ 450
DECFSZ............................................................................ 451
Default System Clock.......................................................... 49
Details on Individual Family Members ................................ 11
Development Support ....................................................... 481
Device Overview ................................................................... 9
Features (64-Pin Devices) .......................................... 12
Features (80-Pin Devices) .......................................... 12
Direct Addressing.............................................................. 106
E
Effect on Standard PIC18 Instructions.............................. 478
Effects of Power-Managed Modes on Various
Clock Sources ............................................................ 55
Electrical Characteristics .................................................. 485
Enhanced Capture/Compare/PWM (ECCP)..................... 259
Capture Mode. See Capture.
Compare Mode. See Compare.
Enhanced PWM Mode.............................................. 265
Auto-Restart ..................................................... 274
Auto-Shutdown................................................. 272
Direction Change in Full-Bridge
Output Mode............................................. 271
Full-Bridge Application...................................... 269
Full-Bridge Mode .............................................. 269
Half-Bridge Application..................................... 268
Half-Bridge Application Examples .................... 275
Half-Bridge Mode.............................................. 268
Output Relationships (Active-High and
Active-Low).............................................. 266
Output Relationships Diagram.......................... 267
Programmable Dead-Band Delay..................... 275
Shoot-Through Current..................................... 275
Start-up Considerations.................................... 272
Outputs and Configuration........................................ 262
Timer Resources ...................................................... 262
Enhanced Capture/Compare/PWM (ECCP)
and Timer1/2/3/4/6/8/10/12
Associated Registers................................................ 279
Enhanced Universal Synchronous Asynchronous Receiver
Transmitter (EUSART). See EUSART.
Equations
A/D Acquisition Time ................................................ 361
A/D Minimum Charging Time ................................... 361
Calculating the Minimum Required
Acquisition Time ............................................... 361
Errata.................................................................................... 8
EUSART
Asynchronous Mode................................................. 337
12-Bit Break Transmit and Receive.................. 344
Associated Registers, Receive......................... 341
Associated Registers, Transmit........................ 339
Auto-Wake-up on Sync Break .......................... 342
Receiver ........................................................... 340
Setting Up 9-Bit Mode with Address Detect ..... 340
Transmitter ....................................................... 337
Baud Rate Generator
Operation in Power-Managed Mode................. 331
Baud Rate Generator (BRG) .................................... 331
Associated Registers........................................ 332
Auto-Baud Rate Detect..................................... 335
Baud Rate Error, Calculating............................ 332
Baud Rates, Asynchronous Modes .................. 333
High Baud Rate Select (BRGH Bit) .................. 331
Sampling .......................................................... 331
Synchronous Master Mode....................................... 345
Associated Registers, Receive......................... 348
Associated Registers, Transmit........................ 346
Reception ......................................................... 347
Transmission .................................................... 345
Synchronous Slave Mode......................................... 349
Associated Registers, Receive......................... 350
Associated Registers, Transmit........................ 349
Reception ......................................................... 350
Transmission .................................................... 349
PIC18F87K22 FAMILY
DS39960C-page 536 2011 Microchip Technology Inc.
Extended Instruction Set
ADDFSR ................................................................... 474
ADDULNK................................................................. 474
CALLW...................................................................... 475
MOVSF ..................................................................... 475
MOVSS ..................................................................... 476
PUSHL ...................................................................... 476
SUBFSR ................................................................... 477
SUBULNK ................................................................. 477
External Memory Bus........................................................ 121
16-Bit Byte Select Mode ........................................... 127
16-Bit Byte Write Mode .............................................125
16-Bit Data Width Modes .......................................... 124
16-Bit Mode Timing................................................... 128
16-Bit Word Write Mode............................................ 126
8-Bit Data Width Mode..............................................129
8-Bit Mode Timing ..................................................... 130
Address and Data Lines for Different
Address and Data Widths (table) ...................... 123
Address and Data Width ........................................... 123
Address Shifting........................................................ 123
Control ...................................................................... 122
I/O Port Functions ..................................................... 121
Operation in Power-Managed Modes ....................... 131
Program Memory Modes ..........................................124
Extended Microcontroller .................................. 124
Microcontroller .................................................. 124
Wait States................................................................ 124
Weak Pull-ups on Port Pins ...................................... 124
External Oscillator Modes
Clock Input (EC Modes).............................................. 51
HS ............................................................................... 50
F
Fail-Safe Clock Monitor............................................. 403, 424
Exiting Operation ...................................................... 424
Interrupts in Power-Managed Modes ........................ 425
POR or Wake from Sleep .........................................425
WDT During Oscillator Failure .................................. 424
Fast Register Stack............................................................. 91
Firmware Instructions........................................................431
Flash Program Memory..................................................... 111
Associated Registers ................................................ 120
Control Registers ...................................................... 112
EECON1 and EECON2 .................................... 112
TABLAT (Table Latch) Register........................ 114
TBLPTR (Table Pointer) Register ..................... 114
Erase Sequence ....................................................... 116
Erasing ...................................................................... 116
Operation During Code-Protect ................................ 120
Reading..................................................................... 115
Table Pointer
Boundaries Based on Operation....................... 114
Table Pointer Boundaries ......................................... 114
Table Reads and Table Writes ................................. 111
Write Sequence ........................................................ 118
Writing....................................................................... 117
Protection Against Spurious Writes .................. 120
Unexpected Termination................................... 120
Write Verify .......................................................120
FSCM. See Fail-Safe Clock Monitor.
G
GOTO................................................................................ 452
H
Hardware Multiplier........................................................... 139
8 x 8 Multiplication Algorithms .................................. 139
Operation.................................................................. 139
Performance Comparison (table).............................. 139
High/Low-Voltage Detect .................................................. 379
Applications .............................................................. 383
Associated Registers................................................ 384
Current Consumption................................................ 381
Effects of a Reset ..................................................... 384
Operation.................................................................. 380
During Sleep..................................................... 384
Setup ........................................................................ 381
Start-up Time............................................................ 381
Typical Application.................................................... 383
HLVD. See High/Low-Voltage Detect. .............................. 379
I
I/O Ports............................................................................ 165
Open-Drain Outputs.................................................. 167
Output Pin Drive ....................................................... 165
Pin Capabilities......................................................... 165
Pull-up Configuration ................................................ 165
I2C Mode (MSSP)
Acknowledge Sequence Timing ............................... 320
Associated Registers................................................ 326
Baud Rate Generator ............................................... 313
Bus Collision
During a Repeated Start Condition................... 324
During a Stop Condition ................................... 325
Clock Arbitration ....................................................... 314
Clock Stretching........................................................ 306
10-Bit Slave Receive Mode (SEN = 1) ............. 306
10-Bit Slave Transmit Mode ............................. 306
7-Bit Slave Receive Mode (SEN = 1) ............... 306
7-Bit Slave Transmit Mode ............................... 306
Clock Synchronization and the CKP bit.................... 307
Effects of a Reset ..................................................... 321
General Call Address Support .................................. 310
I2C Clock Rate w/BRG.............................................. 313
Master Mode............................................................. 311
Operation.......................................................... 312
Reception ......................................................... 317
Repeated Start Condition Timing ..................... 316
Start Condition Timing ...................................... 315
Transmission .................................................... 317
Multi-Master Communication, Bus Collision
and Arbitration .................................................. 321
Multi-Master Mode.................................................... 321
Operation.................................................................. 296
Read/Write Bit Information (R/W Bit)................ 296, 299
Registers .................................................................. 291
Serial Clock (RC3/SCKx/SCLx)................................ 299
Slave Mode............................................................... 296
Address Masking Modes
5-Bit .......................................................... 297
7-Bit .......................................................... 298
Addressing........................................................ 296
Reception ......................................................... 299
Transmission .................................................... 299
Sleep Operation........................................................ 321
Stop Condition Timing .............................................. 320
ID Locations.............................................................. 403, 429
2011 Microchip Technology Inc. DS39960C-page 537
PIC18F87K22 FAMILY
INCF.................................................................................. 452
INCFSZ ............................................................................. 453
In-Circuit Debugger ........................................................... 429
In-Circuit Serial Programming (ICSP) ....................... 403, 429
Indexed Literal Offset Addressing
and Standard PIC18 Instructions .............................. 478
Indexed Literal Offset Mode .............................................. 478
Indirect Addressing ........................................................... 106
INFSNZ ............................................................................. 453
Initialization Conditions for All Registers....................... 79–86
Instruction Cycle ................................................................. 92
Clocking Scheme........................................................ 92
Flow/Pipelining............................................................ 92
Instruction Set ................................................................... 431
ADDLW ..................................................................... 437
ADDWF..................................................................... 437
ADDWF (Indexed Literal Offset Mode) ..................... 479
ADDWFC .................................................................. 438
ANDLW ..................................................................... 438
ANDWF..................................................................... 439
BC ............................................................................. 439
BCF........................................................................... 440
BN ............................................................................. 440
BNC .......................................................................... 441
BNN .......................................................................... 441
BNOV........................................................................ 442
BNZ........................................................................... 442
BOV .......................................................................... 445
BRA........................................................................... 443
BSF........................................................................... 443
BSF (Indexed Literal Offset Mode) ........................... 479
BTFSC ...................................................................... 444
BTFSS ...................................................................... 444
BTG........................................................................... 445
BZ ............................................................................. 446
CALL ......................................................................... 446
CLRF......................................................................... 447
CLRWDT................................................................... 447
COMF ....................................................................... 448
CPFSEQ ................................................................... 448
CPFSGT ................................................................... 449
CPFSLT .................................................................... 449
DAW.......................................................................... 450
DCFSNZ ................................................................... 451
DECF ........................................................................ 450
DECFSZ.................................................................... 451
Extended Instructions ............................................... 473
Considerations when Enabling ......................... 478
Syntax............................................................... 473
Use with MPLAB IDE Tools .............................. 480
General Format......................................................... 433
GOTO ....................................................................... 452
INCF.......................................................................... 452
INCFSZ ..................................................................... 453
INFSNZ ..................................................................... 453
IORLW ...................................................................... 454
IORWF ...................................................................... 454
LFSR......................................................................... 455
MOVF........................................................................ 455
MOVFF ..................................................................... 456
MOVLB ..................................................................... 456
MOVLW .................................................................... 457
MOVWF .................................................................... 457
MULLW ..................................................................... 458
MULWF..................................................................... 458
NEGF........................................................................ 459
NOP.......................................................................... 459
Opcode Field Descriptions ....................................... 432
POP .......................................................................... 460
PUSH........................................................................ 460
RCALL ...................................................................... 461
RESET...................................................................... 461
RETFIE..................................................................... 462
RETLW ..................................................................... 462
RETURN................................................................... 463
RLCF ........................................................................ 463
RLNCF...................................................................... 464
RRCF........................................................................ 464
RRNCF ..................................................................... 465
SETF ........................................................................ 465
SETF (Indexed Literal Offset Mode)......................... 479
SLEEP ...................................................................... 466
Standard Instructions................................................ 431
SUBFWB .................................................................. 466
SUBLW..................................................................... 467
SUBWF..................................................................... 467
SUBWFB .................................................................. 468
SWAPF..................................................................... 468
TBLRD...................................................................... 469
TBLWT ..................................................................... 470
TSTFSZ .................................................................... 471
XORLW .................................................................... 471
XORWF .................................................................... 472
INTCON Register
RBIF Bit .................................................................... 172
Inter-Integrated Circuit. See I2C.
Internal Oscillator Block ...................................................... 52
Adjustment.................................................................. 53
INTIO Modes .............................................................. 52
INTOSC
Frequency Drift ................................................... 53
Output Frequency............................................... 53
INTPLL Modes............................................................ 52
Internal RC Oscillator
Use with WDT........................................................... 419
Internal Voltage Regulator Specifications......................... 500
Internet Address ............................................................... 544
Interrupt Sources .............................................................. 403
A/D Conversion Complete ........................................ 360
Capture Complete (CCP) ......................................... 251
Capture Complete (ECCP) ....................................... 263
Compare Complete (CCP) ....................................... 252
Compare Complete (ECCP) ..................................... 264
Interrupt-on-Change (RB7:RB4)............................... 172
TMR0 Overflow......................................................... 195
TMR1 Overflow......................................................... 202
TMR2 to PR2 Match (PWM)..................................... 255
TMRx Overflow................................................. 211, 221
Interrupts .......................................................................... 141
Associated Registers................................................ 164
During, Context Saving............................................. 163
INTx Pin.................................................................... 163
PORTB, Interrupt-on-Change................................... 163
TMR0........................................................................ 163
Interrupts, Flag Bits
Interrupt-on-Change (RB7:RB4) Flag (RBIF Bit) ...... 172
PIC18F87K22 FAMILY
DS39960C-page 538 2011 Microchip Technology Inc.
INTOSC, INTRC. See Internal Oscillator Block.
IORLW .............................................................................. 454
IORWF .............................................................................. 454
L
LFSR ................................................................................. 455
M
Master Clear (MCLR) .......................................................... 75
Master Synchronous Serial Port (MSSP). See MSSP.
Memory Organization.......................................................... 87
Data Memory ..............................................................94
Program Memory Maps .............................................. 87
Memory Programming Requirements ............................... 499
Microchip Internet Web Site.............................................. 544
Migration From PIC18F87J11 and
PIC18F8722 to PIC18F87K22 .................................. 532
MOVF................................................................................ 455
MOVFF.............................................................................. 456
MOVLB.............................................................................. 456
MOVLW............................................................................. 457
MOVSF ............................................................................. 475
MOVSS ............................................................................. 476
MOVWF ............................................................................ 457
MPLAB ASM30 Assembler, Linker, Librarian ................... 482
MPLAB Integrated Development Environment
Software.................................................................... 481
MPLAB PM3 Device Programmer..................................... 484
MPLAB REAL ICE In-Circuit Emulator System.................483
MPLINK Object Linker/MPLIB Object Librarian ................ 482
MSSP
ACK Pulse......................................................... 296, 299
I2C Mode. See I2C Mode.
Module Overview ...................................................... 281
SPI Master/Slave Connection ................................... 285
TMRx Output for Clock Shift ..................................... 224
MULLW ............................................................................. 458
MULWF ............................................................................. 458
N
NEGF ................................................................................ 459
NOP .................................................................................. 459
Notable Differences Between PIC18F87K22,
PIC18F87J11 and PIC18F8722 Families ................. 532
O
On-Chip Voltage
Regulator .................................................................. 421
Disable .............................................................. 421
Enable............................................................... 421
Sleep................................................................. 422
Oscillator Configuration....................................................... 43
EC ............................................................................... 43
ECIO ........................................................................... 43
HS ............................................................................... 43
Internal Oscillator Block .............................................. 52
INTIO1 ........................................................................ 43
INTIO2 ........................................................................ 43
LP................................................................................ 43
RC............................................................................... 43
RCIO ........................................................................... 43
XT ............................................................................... 43
Oscillator Selection ........................................................... 403
Oscillator Start-up Timer (OST) .......................................... 55
Oscillator Switching............................................................. 48
Oscillator Transitions........................................................... 49
Oscillator, Timer1.............................................................. 197
Oscillator, Timer3/5/7........................................................ 211
P
P1A/P1B/P1C/P1D.See Enhanced Capture/Compare/PWM
(ECCP)
Packaging ......................................................................... 525
Details....................................................................... 526
Marking..................................................................... 525
Parallel Slave Port (PSP).................................................. 189
Associated Registers................................................ 191
PORTD ..................................................................... 189
Pin Functions
AVDD..................................................................... 23, 36
AVSS ..................................................................... 36, 23
ENVREG .............................................................. 23, 36
MCLR/RG5 ........................................................... 15, 24
OSC1/CLKI/RA7................................................... 15, 24
OSC2/CLKO/RA6 ................................................. 15, 24
RA0/AN0/ULPWU................................................. 16, 25
RA1/AN1............................................................... 16, 25
RA2/AN2/VREF- .................................................... 16, 25
RA3/AN3/VREF+ ................................................... 16, 25
RA4/T0CKI ........................................................... 16, 25
RA5/AN4/T1CKI/T3G/HLVDIN ............................. 16, 25
RB0/INT0/FLT0........................................................... 26
RB0/INT0/FLTO.......................................................... 17
RB1/INT1.............................................................. 17, 26
RB2/INT2/CTED1 ................................................. 17, 26
RB3/INT3/CTED2/ECCP2/P2A ............................ 17, 26
RB4/KBI0.............................................................. 17, 26
RB5/KBI1/T3CKI/T1G........................................... 17, 26
RB6/KBI2/PGC ..................................................... 17, 26
RB7/KBI3/PGD ..................................................... 17, 26
RC0/SOSCO/SCKLI ................................................... 27
RC0/SOSCO/SCLKI ................................................... 18
RC1/SOSCI/ECCP2/P2A...................................... 18, 27
RC2/ECCP1/P1A.................................................. 18, 27
RC3/SCK1/SCL1 .................................................. 18, 27
RC4/SDI1/SDA1 ................................................... 18, 27
RC5/SDO1............................................................ 18, 27
RC6/TX1/CK1 ....................................................... 18, 27
RC7/RX1/DT1....................................................... 18, 27
RD0/PSP0/CTPLS...................................................... 19
RD0/PSP0/CTPLS/AD0.............................................. 28
RD1/PSP1/T5CKI/T7G ............................................... 19
RD1/T5CKI/T7G/PSP1/AD1 ....................................... 28
RD2/PSP2 .................................................................. 19
RD2/PSP2/AD2 .......................................................... 28
RD3/PSP3 .................................................................. 19
RD3/PSP3/AD3 .......................................................... 28
RD4/PSP4/SDO2........................................................ 19
RD4/SDO2/PSP4/AD4................................................ 28
RD5/PSP5/SDI2/SDA2............................................... 19
RD5/SDI2/SDA2/PSP5/AD5....................................... 28
RD6/PSP6/SCK2/SCL2.............................................. 19
RD6/SCK2/SCL2/PSP6/AD6...................................... 29
RD7/PSP7/SS2 .......................................................... 19
RD7/SS2/PSP7/AD7................................................... 29
RE0/P2D/RD/AD8....................................................... 30
RE0/RD/P2D............................................................... 20
RE1/P2C/WR/AD9...................................................... 30
RE1/WR/P2C.............................................................. 20
RE2/CS/P2B/CCP10 .................................................. 20
RE2/P2B/CCP10/CS/AD10 ........................................ 30
RE3/P3C/CCP9/REFO ............................................... 20
2011 Microchip Technology Inc. DS39960C-page 539
PIC18F87K22 FAMILY
RE3/P3C/CCP9/REFO/AD11 ..................................... 30
RE4/P3B/CCP8........................................................... 20
RE4/P3B/CCP8/AD12................................................. 30
RE5/P1C/CCP7 .......................................................... 20
RE5/P1C/CCP7/AD13 ................................................ 30
RE6/P1B/CCP6........................................................... 20
RE6/P1B/CCP6/AD14................................................. 31
RE7/ECCP2/P2A ........................................................ 20
RE7/ECCP2/P2A/AD15 .............................................. 31
RF1/AN6/C2OUT/CTDIN...................................... 21, 32
RF2/AN7/C1OUT .................................................. 21, 32
RF3/AN8/C2INB/CTMUI ....................................... 21, 32
RF4/AN9/C2INA.................................................... 21, 32
RF5/AN10/C1INB........................................................ 32
RF5/AN10/CVREF/C1INB............................................ 21
RF6/AN11/C1INA.................................................. 21, 32
RF7/AN5/SS1 ....................................................... 21, 32
RG0/ECCP3/P3A.................................................. 22, 33
RG1/TX2/CK2/AN19/C3OUT................................ 22, 33
RG2/RX2/DT2/AN18/C3INA ................................. 22, 33
RG3/CCP4/AN17/P3D/C3INB .............................. 22, 33
RG4/RTCC/T7CKI/T5G/CCP5/AN16/
P1D/C3INC ................................................... 22, 33
RH0/AN23/A16 ........................................................... 34
RH1/AN22/A17 ........................................................... 34
RH2/AN21/A18 ........................................................... 34
RH3/AN20/A19 ........................................................... 34
RH4/CCP9/P3C/AN12/C2INC .................................... 34
RH5/CCP8/P3B/AN13/C2IND..................................... 34
RH6/CCP7/P1C/AN14/C1INC .................................... 34
RH7/CCP6/P1B/AN15 ................................................ 35
RJ0/ALE...................................................................... 36
RJ1/OE ....................................................................... 36
RJ2/WRL..................................................................... 36
RJ3/WRH .................................................................... 36
RJ4/BA0...................................................................... 36
RJ5/CE........................................................................ 36
RJ6/LB ........................................................................ 36
RJ7/UB........................................................................ 36
VDD ....................................................................... 23, 36
VDDCORE/VCAP...................................................... 23, 36
VSS........................................................................ 23, 36
Pinout I/O Descriptions
PIC18F6XK22 ............................................................. 15
PIC18F8XK22 ............................................................. 24
PLL...................................................................................... 51
HSPLL and ECPLL Oscillator Modes ......................... 51
Use with HF-INTOSC.................................................. 51
POP .................................................................................. 460
POR. See Power-on Reset.
PORTA
Associated Registers ................................................ 171
LATA Register........................................................... 170
PORTA Register ....................................................... 170
TRISA Register ......................................................... 170
PORTB
Associated Registers ................................................ 173
LATB Register........................................................... 172
PORTB Register ....................................................... 172
RB7:RB4 Interrupt-on-Change Flag (RBIF Bit)......... 172
TRISB Register ......................................................... 172
PORTC
Associated Registers................................................ 175
LATC Register .......................................................... 174
PORTC Register....................................................... 174
RC3/SCKx/SCLx Pin ................................................ 299
TRISC Register ........................................................ 174
PORTD
Associated Registers................................................ 177
LATD Register .......................................................... 176
PORTD Register....................................................... 176
TRISD Register ........................................................ 176
PORTE
Associated Registers................................................ 180
LATE Register .......................................................... 178
PORTE Register....................................................... 178
RE0/P2D/RD/AD8 Pin .............................................. 189
RE1/P2C/WR/AD9 Pin ............................................. 189
RE2/P2B/CCP10/CS/AD10 Pin ................................ 189
TRISE Register......................................................... 178
PORTF
Associated Registers................................................ 182
LATF Register .......................................................... 181
PORTF Register ....................................................... 181
TRISF Register......................................................... 181
PORTG
Associated Registers................................................ 184
LATG Register.......................................................... 183
PORTG Register ...................................................... 183
TRISG Register ........................................................ 183
PORTH
Associated Registers................................................ 187
LATH Register .......................................................... 185
PORTH Register....................................................... 185
TRISH Register ........................................................ 185
PORTJ
Associated Registers................................................ 188
LATJ Register........................................................... 187
PORTJ Register ....................................................... 187
TRISJ Register ......................................................... 187
Power-Managed Modes...................................................... 57
and EUSART Operation ........................................... 331
and PWM Operation ................................................. 279
and SPI Operation .................................................... 289
Clock Transitions and Status Indicators ..................... 58
Entering ...................................................................... 57
Exiting Idle and Sleep Modes ..................................... 69
by Interrupt ......................................................... 69
by Reset ............................................................. 69
by WDT Time-out ............................................... 69
Without an Oscillator Start-up Delay .................. 69
Idle Modes .................................................................. 62
PRI_IDLE ........................................................... 63
RC_IDLE ............................................................ 64
SEC_IDLE .......................................................... 63
Multiple Sleep Commands.......................................... 58
Run Modes ................................................................. 58
PRI_RUN............................................................ 58
RC_RUN............................................................. 60
SEC_RUN .......................................................... 58
Selecting..................................................................... 57
Sleep Mode ................................................................ 62
OSC1 and OSC2 Pin States............................... 55
Summary (table) ......................................................... 57
PIC18F87K22 FAMILY
DS39960C-page 540 2011 Microchip Technology Inc.
Power-on Reset (POR) ....................................................... 75
Power-up Delays................................................................. 55
Power-up Timer (PWRT)............................................... 55, 76
Time-out Sequence..................................................... 76
Prescaler, Timer0.............................................................. 195
Prescaler, Timer2.............................................................. 256
PRI_IDLE Mode .................................................................. 63
PRI_RUN Mode .................................................................. 58
Program Counter................................................................. 89
PCL, PCH and PCU Registers.................................... 89
PCLATH and PCLATU Registers ............................... 89
Program Memory
Code Protection ........................................................ 427
Extended Instruction Set........................................... 107
Hard Memory Vectors .................................................88
Instructions.................................................................. 93
Two-Word ........................................................... 93
Interrupt Vector ........................................................... 88
Look-up Tables ........................................................... 91
Memory Maps ............................................................. 87
Reset Vector ............................................................... 88
Program Verification and Code Protection........................ 426
Associated Registers ................................................ 427
Programming, Device Instructions .................................... 431
PSP.See Parallel Slave Port.
Pulse Steering................................................................... 276
Pulse-Width Modulation. See PWM (CCP Module).
PUSH ................................................................................ 460
PUSH and POP Instructions ............................................... 90
PUSHL .............................................................................. 476
PWM (CCP Module)
Associated Registers ................................................ 256
Duty Cycle................................................................. 256
Example Frequencies/Resolutions ........................... 256
Period........................................................................ 255
Setup for PWM Operation......................................... 256
TMR2 to PR2 Match ................................................. 255
PWM (ECCP Module)
Effects of a Reset......................................................279
Operation in Power-Managed Modes ....................... 279
Operation with Fail-Safe Clock Monitor .................... 279
Pulse Steering Mode.................................................276
Steering Synchronization .......................................... 278
PWM Mode. See Enhanced Capture/Compare/PWM.
Q
Q Clock ............................................................................. 256
R
RAM. See Data Memory.
RC_IDLE Mode ................................................................... 64
RC_RUN Mode ................................................................... 60
RCALL............................................................................... 461
RCON Register
Bit Status During Initialization ..................................... 78
Reader Response ............................................................. 545
Real-Time Clock and Calendar (RTCC)............................ 227
Registers................................................................... 228
Reference Clock Output...................................................... 53
Register File........................................................................ 96
Register File Summary................................................ 98–103
Registers
ADCON0 (A/D Control 0).......................................... 352
ADCON1 (A/D Control 1).......................................... 353
ADCON2 (A/D Control 2).......................................... 354
ADRESH (A/D Result High Byte Left Justified,
ADFM = 0) ........................................................ 355
ADRESH (A/D Result High Byte Right Justified,
ADFM = 1) ........................................................ 356
ADRESL (A/D Result High Byte Left Justified,
ADFM = 0) ........................................................ 356
ADRESL (A/D Result Low Byte Right Justified,
ADFM = 1) ........................................................ 356
ALRMCFG (Alarm Configuration) ............................. 231
ALRMDAY (Alarm Day Value).................................. 235
ALRMHR (Alarm Hours Value)................................. 236
ALRMMIN (Alarm Minutes Value)............................. 236
ALRMMNTH (Alarm Month Value) ........................... 235
ALRMRPT (Alarm Repeat) ....................................... 232
ALRMSEC (Alarm Seconds Value) .......................... 236
ALRMWD (Alarm Weekday Value)........................... 235
ANCON0 (A/D Port Configuration 0) ........................ 357
ANCON1 (A/D Port Configuration 1) ........................ 357
ANCON2 (A/D Port Configuration 2) ........................ 358
BAUDCONx (Baud Rate Control) ............................. 330
CCPRxH (CCPx Period High Byte) .......................... 248
CCPRxL (CCPx Period Low Byte)............................ 248
CCPTMRS0 (CCP Timer Select 0)........................... 261
CCPTMRS1 (CCP Timer Select 1)........................... 246
CCPTMRS2 (CCP Timer Select 2)........................... 247
CCPxCON (CCP4-CCP10 Control) .......................... 245
CCPxCON (Enhanced Capture/
Compare/PWM x Control) ................................ 260
CMSTAT (Comparator Status) ................................. 369
CMxCON (Comparator Control x)............................. 368
CONFIG1H (Configuration 1 High)........................... 406
CONFIG1L (Configuration 1 Low) ............................ 405
CONFIG2H (Configuration 2 High)........................... 408
CONFIG2L (Configuration 2 Low) ............................ 407
CONFIG3H (Configuration 3 High)........................... 410
CONFIG3L (Configuration 3 Low) ............................ 409
CONFIG4L (Configuration 4 Low) ............................ 411
CONFIG5H (Configuration 5 High)........................... 413
CONFIG5L (Configuration 5 Low) ............................ 412
CONFIG6H (Configuration 6 High)........................... 415
CONFIG6L (Configuration 6 Low) ............................ 414
CONFIG7H (Configuration 7 High)........................... 417
CONFIG7L (Configuration 7 Low) ............................ 416
CTMUCONH (CTMU Control High) .......................... 386
CTMUCONL (CTMU Control Low) ........................... 387
CTMUICON (CTMU Current Control)....................... 388
CVRCON (Comparator Voltage Reference
Control)............................................................. 375
DAY (Day Value) ...................................................... 233
DEVID1 (Device ID 1)............................................... 418
DEVID2 (Device ID 2)............................................... 418
ECCPxAS (ECCPx Auto-Shutdown Control)............ 273
ECCPxDEL (Enhanced PWM Control) ..................... 276
EECON1 (Data EEPROM Control 1)........................ 134
EECON1 (EEPROM Control 1) ................................ 113
HLVDCON (High/Low-Voltage Detect Control) ........ 379
HOUR (Hour Value).................................................. 234
INTCON (Interrupt Control)....................................... 143
2011 Microchip Technology Inc. DS39960C-page 541
PIC18F87K22 FAMILY
INTCON2 (Interrupt Control 2).................................. 144
INTCON3 (Interrupt Control 3).................................. 145
IPR1 (Peripheral Interrupt Priority 1)......................... 157
IPR2 (Peripheral Interrupt Priority 2)......................... 158
IPR3 (Peripheral Interrupt Priority 3)......................... 159
IPR4 (Peripheral Interrupt Priority 4)......................... 159
IPR5 (Peripheral Interrupt Priority 5)......................... 160
IPR6 (Peripheral Interrupt Priority 6)......................... 161
MEMCON (External Memory Bus Control) ............... 122
MINUTE (Minute Value)............................................ 234
MONTH (Month Value) ............................................. 233
ODCON1 (Peripheral Open-Drain Control 1)............ 167
ODCON2 (Peripheral Open-Drain Control 2)............ 168
ODCON3 (Peripheral Open-Drain Control 3)............ 169
OSCCON (Oscillator Control) ..................................... 45
OSCCON2 (Oscillator Control 2) ........................ 46, 214
OSCTUNE (Oscillator Tuning) .................................... 47
PADCFG1 (Pad Configuration)......................... 166, 230
PIE1 (Peripheral Interrupt Enable 1)......................... 152
PIE2 (Peripheral Interrupt Enable 2)......................... 153
PIE3 (Peripheral Interrupt Enable 3)......................... 154
PIE4 (Peripheral Interrupt Enable 4)......................... 154
PIE5 (Peripheral Interrupt Enable 5)......................... 155
PIE6 (Peripheral Interrupt Enable 6)......................... 156
PIR1 (Peripheral Interrupt Request (Flag) 1) ............ 146
PIR2 (Peripheral Interrupt Request (Flag) 2) ............ 147
PIR3 (Peripheral Interrupt Request (Flag) 3) ............ 148
PIR4 (Peripheral Interrupt Request (Flag) 4) ............ 149
PIR5 (Peripheral Interrupt Request (Flag) 5) ............ 150
PIR6 (Peripheral Interrupt Request (Flag) 6) ............ 151
PMD0 (Peripheral Module Disable 0) ......................... 68
PMD1 (Peripheral Module Disable 1) ......................... 67
PMD2 (Peripheral Module Disable 2) ......................... 66
PMD3 (Peripheral Module Disable 3) ......................... 65
PSPCON (Parallel Slave Port Control) ..................... 190
PSTRxCON (Pulse Steering Control) ....................... 277
RCON (Reset Control)........................................ 74, 162
RCSTAx (Receive Status and Control)..................... 329
REFOCON (Reference Oscillator Control) ................. 54
Reserved................................................................... 232
RTCCAL (RTCC Calibration).................................... 230
RTCCFG (RTCC Configuration) ............................... 229
SECOND (Second Value)......................................... 234
SSPxCON1 (MSSPx Control 1, I2C Mode)............... 293
SSPxCON1 (MSSPx Control 1, SPI Mode) .............. 283
SSPxCON2 (MSSPx Control 2, I2C
Master Mode).................................................... 294
SSPxCON2 (MSSPx Control 2, I2C Slave Mode)..... 295
SSPxMSK (I2C Slave Address Mask,
7-Bit Masking Mode)......................................... 295
SSPxSTAT (MSSPx Status, I2C Mode).................... 292
SSPxSTAT (MSSPx Status, SPI Mode) ................... 282
STATUS.................................................................... 104
STKPTR (Stack Pointer) ............................................. 90
T0CON (Timer0 Control)........................................... 193
T1CON (Timer1 Control)........................................... 197
T1GCON (Timer1 Gate Control) ............................... 198
T2CON (Timer2 Control)........................................... 209
TxCON (Timerx Control, Timer3/5/7)........................ 212
TxCON (Timerx Control, Timer4/6/8/10/12).............. 224
TxGCON (Timerx Gate Control) ............................... 213
TXSTAx (Transmit Status and Control) .................... 328
WDTCON (Watchdog Timer Control) ....................... 420
WEEKDAY (Weekday Value) ................................... 233
YEAR (Year Value)................................................... 232
RESET.............................................................................. 461
Reset .................................................................................. 73
Brown-out Reset (BOR).............................................. 73
Configuration Mismatch (CM)..................................... 73
MCLR, During Power-Managed Modes...................... 73
MCLR, Normal Operation ........................................... 73
Power-on Reset (POR)............................................... 73
RESET Instruction...................................................... 73
Stack Full.................................................................... 73
Stack Underflow ......................................................... 73
Watchdog Timer (WDT).............................................. 73
Resets .............................................................................. 403
Brown-out Reset (BOR)............................................ 403
Oscillator Start-up Timer (OST)................................ 403
Power-on Reset (POR)............................................. 403
Power-up Timer (PWRT) .......................................... 403
RETFIE............................................................................. 462
RETLW ............................................................................. 462
RETURN........................................................................... 463
Return Address Stack......................................................... 89
Return Stack Pointer (STKPTR) ......................................... 90
Revision History................................................................ 531
RLCF ................................................................................ 463
RLNCF.............................................................................. 464
RRCF................................................................................ 464
RRNCF ............................................................................. 465
RTCC
Alarm ........................................................................ 240
Configuring ....................................................... 240
Interrupt ............................................................ 241
Mask Settings................................................... 241
Alarm Value Registers (ALRMVAL).......................... 235
Associated Alarm Value Registers ........................... 243
Associated Control Registers ................................... 243
Associated Value Registers...................................... 243
Control Registers...................................................... 229
Operation.................................................................. 237
Calibration ........................................................ 240
Clock Source .................................................... 238
Digit Carry Rules .............................................. 238
General Functionality........................................ 239
Leap Year......................................................... 239
Register Mapping ............................................. 239
ALRMVAL................................................. 240
RTCVAL ................................................... 239
Safety Window for Register Reads
and Writes ................................................ 239
Write Lock......................................................... 239
Register Interface ..................................................... 237
Register Maps .......................................................... 243
Reset ........................................................................ 242
Device .............................................................. 242
Power-on Reset (POR)..................................... 242
Sleep Mode .............................................................. 242
Value Registers (RTCVAL)....................................... 232
RTCEN Bit Write............................................................... 237
S
SCKx ................................................................................ 281
SDIx.................................................................................. 281
SDOx ................................................................................ 281
SEC_IDLE Mode ................................................................ 63
SEC_RUN Mode................................................................. 58
PIC18F87K22 FAMILY
DS39960C-page 542 2011 Microchip Technology Inc.
Selective Peripheral Module Control................................... 64
Serial Clock, SCKx............................................................ 281
Serial Data In (SDIx) ......................................................... 281
Serial Data Out (SDOx)..................................................... 281
Serial Peripheral Interface. See SPI Mode.
SETF ................................................................................. 465
Shoot-Through Current ..................................................... 275
Slave Select (SSx) ............................................................ 281
SLEEP............................................................................... 466
Software Simulator (MPLAB SIM).....................................483
Special Event Trigger. See Compare (CCP Module).
Special Event Trigger. See Compare (ECCP Mode).
SPI Mode (MSSP)............................................................. 281
Associated Registers ................................................ 290
Bus Mode Compatibility ............................................ 289
Clock Speed, Interactions ......................................... 289
Effects of a Reset......................................................289
Enabling SPI I/O ....................................................... 285
Master Mode ............................................................. 286
Master/Slave Connection .......................................... 285
Operation .................................................................. 284
Operation in Power-Managed Modes ....................... 289
Serial Clock............................................................... 281
Serial Data In ............................................................281
Serial Data Out .........................................................281
Slave Mode ...............................................................287
Slave Select ..............................................................281
Slave Select Synchronization ...................................287
SPI Clock ..................................................................286
SSPxBUF Register ...................................................286
SSPxSR Register......................................................286
Typical Connection ...................................................285
SSPOV.............................................................................. 317
SSPOV Status Flag........................................................... 317
SSPxSTAT Register
R/W Bit.............................................................. 296, 299
.......................................................................................... 281
Stack Full/Underflow Resets ............................................... 91
SUBFSR............................................................................ 477
SUBFWB........................................................................... 466
SUBLW ............................................................................. 467
SUBULNK ......................................................................... 477
SUBWF ............................................................................. 467
SUBWFB........................................................................... 468
SWAPF ............................................................................. 468
T
Table Pointer Operations (table)....................................... 114
Table Reads/Table Writes................................................... 91
TBLRD .............................................................................. 469
TBLWT .............................................................................. 470
Timer0 ............................................................................... 193
Associated Registers ................................................ 195
Operation .................................................................. 194
Overflow Interrupt ..................................................... 195
Prescaler................................................................... 195
Switching Assignment.......................................195
Prescaler Assignment (PSA Bit) ............................... 195
Prescaler Select (T0PS2:T0PS0 Bits) ......................195
Reads and Writes in 16-Bit Mode ............................. 194
Source Edge Select (T0SE Bit)................................. 194
Source Select (T0CS Bit).......................................... 194
Timer1............................................................................... 197
16-Bit Read/Write Mode ........................................... 201
Associated Registers................................................ 207
Clock Source Selection............................................. 199
Gate.......................................................................... 203
Interrupt .................................................................... 202
Operation.................................................................. 199
Oscillator................................................................... 197
SOSC Layout Considerations........................... 202
Oscillator, as Secondary Clock................................... 48
Resetting, Using the ECCP Special
Event Trigger .................................................... 203
SOSC Oscillator........................................................ 201
TMR1H Register....................................................... 197
TMR1L Register........................................................ 197
Using SOSC as a Clock Source ............................... 202
Timer2............................................................................... 209
Associated Registers................................................ 210
Interrupt .................................................................... 210
Operation.................................................................. 209
Output....................................................................... 210
PR2 Register ............................................................ 255
TMR2 to PR2 Match Interrupt................................... 255
Timer3/5/7......................................................................... 211
16-Bit Read/Write Mode ........................................... 216
Associated Registers................................................ 222
Gates ........................................................................ 217
Operation.................................................................. 215
Oscillator................................................................... 211
Overflow Interrupt ............................................. 211, 221
Special Event Trigger (ECCP).................................. 221
TMRxH Register ....................................................... 211
TMRxL Register........................................................ 211
Using SOSCO Oscillator as Clock Source ............... 216
Timer4
MSSP Clock Shift ..................................................... 224
Timer4/6/8/10/12............................................................... 223
Associated Registers................................................ 225
Interrupt .................................................................... 224
Operation.................................................................. 223
Output....................................................................... 224
Postscaler. See Postscaler, Timer4/6/8/10/12.
Prescaler. See Prescaler, Timer4/6/8/10/12.
PRx Register............................................................. 223
TMRx Register.......................................................... 223
Timing Diagrams
A/D Conversion......................................................... 524
Asynchronous Reception.......................................... 341
Asynchronous Transmission..................................... 338
Asynchronous Transmission (Back-to-Back)............ 338
Automatic Baud Rate Calculation ............................. 336
Auto-Wake-up Bit (WUE) During Normal
Operation.......................................................... 343
Auto-Wake-up Bit (WUE) During Sleep.................... 343
Baud Rate Generator with Clock Arbitration............. 314
BRG Overflow Sequence.......................................... 336
BRG Reset Due to SDAx Arbitration During
Start Condition.................................................. 323
Brown-out Reset (BOR)............................................ 509
Bus Collision During Repeated Start
Condition (Case 1)............................................ 324
Bus Collision During Repeated Start
Condition (Case 2)............................................ 324
2011 Microchip Technology Inc. DS39960C-page 543
PIC18F87K22 FAMILY
Bus Collision During Start Condition (SCLx = 0) ...... 323
Bus Collision During Start Condition
(SDAx Only)..................................................... 322
Bus Collision During Stop Condition (Case 1) .......... 325
Bus Collision During Stop Condition (Case 2) .......... 325
Bus Collision for Transmit and Acknowledge............ 321
Capture/Compare/PWM............................................ 513
CLKO and I/O ........................................................... 505
Clock Synchronization .............................................. 307
Clock/Instruction Cycle ............................................... 92
EUSART Synchronous Transmission
(Master/Slave) .................................................. 522
EUSART/AUSART Synchronous
Receive (Master/Slave) .................................... 522
Example SPI Master Mode (CKE = 0) ...................... 514
Example SPI Master Mode (CKE = 1) ...................... 515
Example SPI Slave Mode (CKE = 0) ........................ 516
Example SPI Slave Mode (CKE = 1) ........................ 517
External Clock........................................................... 503
External Memory Bus for SLEEP (Extended
Microcontroller Mode) ............................... 128, 130
External Memory Bus for TBLRD (Extended
Microcontroller Mode) ............................... 128, 130
Fail-Safe Clock Monitor (FSCM)............................... 425
First Start Bit Timing ................................................. 315
Full-Bridge PWM Output ........................................... 270
Half-Bridge PWM Output .................................. 268, 275
High-Voltage Detect Operation (VDIRMAG = 1)....... 383
HLVD Characteristics................................................ 511
I2C Acknowledge Sequence ..................................... 320
I2C Bus Data............................................................. 519
I2C Bus Start/Stop Bits.............................................. 518
I2C Master Mode (7 or 10-Bit Transmission) ............ 318
I2C Master Mode (7-Bit Reception)........................... 319
I2C Slave Mode (10-Bit Reception, SEN = 0,
ADMSK = 01001).............................................. 303
I2C Slave Mode (10-Bit Reception, SEN = 0) ........... 304
I2C Slave Mode (10-Bit Reception, SEN = 1) ........... 309
I2C Slave Mode (10-Bit Transmission)...................... 305
I2C Slave Mode (7-bit Reception, SEN = 0,
ADMSK = 01011).............................................. 301
I2C Slave Mode (7-Bit Reception, SEN = 0) ............. 300
I2C Slave Mode (7-Bit Reception, SEN = 1) ............. 308
I2C Slave Mode (7-Bit Transmission)........................ 302
I2C Slave Mode General Call Address
Sequence (7 or 10-Bit Addressing Mode)......... 310
I2C Stop Condition Receive or Transmit Mode ......... 320
Low-Voltage Detect Operation (VDIRMAG = 0) ....... 382
MSSP I2C Bus Data.................................................. 520
MSSP I2C Bus Start/Stop Bits .................................. 520
Parallel Slave Port (PSP) Read ................................ 191
Parallel Slave Port (PSP) Write ................................ 190
Program Memory Fetch (8-bit).................................. 506
Program Memory Read............................................. 507
Program Memory Write............................................. 508
PWM Auto-Shutdown with Auto-Restart
Enabled (PxRSEN = 1) ..................................... 274
PWM Auto-Shutdown with Firmware
Restart (PxRSEN = 0)....................................... 274
PWM Direction Change ............................................ 271
PWM Direction Change at Near 100%
Duty Cycle ........................................................ 272
PWM Output ............................................................. 255
PWM Output (Active-High)........................................ 266
PWM Output (Active-Low) ........................................ 267
Repeated Start Condition ......................................... 316
Reset, Watchdog Timer (WDT), Oscillator Start-up
Timer (OST) and Power-up Timer (PWRT) ...... 509
Send Break Character Sequence............................. 344
Slave Synchronization .............................................. 287
Slow Rise Time (MCLR Tied to VDD,
VDD Rise > TPWRT)............................................. 77
SPI Mode (Master Mode) ......................................... 286
SPI Mode (Slave Mode, CKE = 0)............................ 288
SPI Mode (Slave Mode, CKE = 1)............................ 288
Steering Event at Beginning of Instruction
(STRSYNC = 1)................................................ 278
Steering Event at End of Instruction
(STRSYNC = 0)................................................ 278
Synchronous Reception (Master Mode, SREN) ....... 347
Synchronous Transmission ...................................... 345
Synchronous Transmission (Through TXEN) ........... 346
Time-out Sequence on Power-up
(MCLR Not Tied to VDD), Case 1 ....................... 77
Time-out Sequence on Power-up
(MCLR Not Tied to VDD), Case 2 ....................... 77
Time-out Sequence on Power-up
(MCLR Tied to VDD, VDD Rise TPWRT)............... 76
Timer Pulse Generation............................................ 242
Timer0 and Timer1 External Clock ........................... 512
Timer1 Gate Count Enable Mode............................. 204
Timer1 Gate Single Pulse Mode............................... 206
Timer1 Gate Single Pulse/Toggle
Combined Mode ............................................... 207
Timer1 Gate Toggle Mode........................................ 205
Timer3/5/7 Gate Count Enable Mode....................... 217
Timer3/5/7 Gate Single Pulse Mode......................... 219
Timer3/5/7 Gate Single Pulse/Toggle
Combined Mode ............................................... 220
Timer3/5/7 Gate Toggle Mode.................................. 218
Transition for Entry to Idle Mode ................................ 63
Transition for Entry to SEC_RUN Mode ..................... 59
Transition for Entry to Sleep Mode ............................. 62
Transition for Two-Speed Start-up
(INTOSC to HSPLL) ......................................... 423
Transition for Wake from Idle to Run Mode................ 63
Transition for Wake from Sleep (HSPLL) ................... 62
Transition from RC_RUN Mode to
PRI_RUN Mode.................................................. 61
Transition from SEC_RUN Mode to
PRI_RUN Mode (HSPLL) ................................... 59
Transition to RC_RUN Mode...................................... 61
Timing Diagrams and Specifications
Capture/Compare/PWM Requirements.................... 513
CLKO and I/O Requirements............................ 505, 507
EUSART/AUSART Synchronous Receive
Requirements ................................................... 522
EUSART/AUSART Synchronous Transmission
Requirements ................................................... 522
Example SPI Mode Requirements
(Master Mode, CKE = 0)................................... 514
Example SPI Mode Requirements
(Master Mode, CKE = 1)................................... 515
Example SPI Mode Requirements
(Slave Mode, CKE = 0)..................................... 516
Example SPI Slave Mode Requirements
(CKE = 1).......................................................... 517
External Clock Requirements ................................... 503
HLVD Characteristics ............................................... 511
I2C Bus Data Requirements (Slave Mode)............... 519
PIC18F87K22 FAMILY
DS39960C-page 544 2011 Microchip Technology Inc.
I2C Bus Start/Stop Bits Requirements
(Slave Mode)..................................................... 518
Internal RC Accuracy (INTOSC) ............................... 504
MSSP I2C Bus Data Requirements .......................... 521
MSSP I2C Bus Start/Stop Bits Requirements ........... 520
PLL Clock.................................................................. 504
Program Memory Fetch Requirements (8-bit)........... 506
Program Memory Write Requirements ..................... 508
Reset, Watchdog Timer, Oscillator Start-up
Timer, Power-up Timer and Brown-out Reset Re-
quirements ........................................................ 510
Timer0 and Timer1 External Clock Requirements .... 512
Top-of-Stack Access........................................................... 89
TSTFSZ............................................................................. 471
Two-Speed Start-up .................................................. 403, 423
IESO (CONFIG1H, Internal/External Oscillator
Switchover Bit ................................................... 406
Two-Word Instructions
Example Cases........................................................... 93
TXSTAx Register
BRGH Bit .................................................................. 331
U
Ultra Low-Power Wake-up
Exit Delay ................................................................... 71
Overview..................................................................... 70
V
Voltage Reference Specifications..................................... 500
W
Watchdog Timer (WDT)............................................ 403, 419
Associated Registers................................................ 420
Control Register........................................................ 420
During Oscillator Failure ........................................... 424
Programming Considerations ................................... 419
WCOL ....................................................... 315, 316, 317, 320
WCOL Status Flag.................................... 315, 316, 317, 320
WWW Address ................................................................. 544
WWW, On-Line Support ....................................................... 8
X
XORLW............................................................................. 471
XORWF ............................................................................ 472
2011 Microchip Technology Inc. DS39960C-page 545
PIC18F87K22 FAMILY
THE MICROCHIP WEB SITE
Microchip provides online support via our WWW site at
www.microchip.com. This web site is used as a means
to make files and information easily available to
customers. Accessible by using your favorite Internet
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information:
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CUSTOMER CHANGE NOTIFICATION
SERVICE
Microchip’s customer notification service helps keep
customers current on Microchip products. Subscribers
will receive e-mail notification whenever there are
changes, updates, revisions or errata related to a
specified product family or development tool of interest.
To register, access the Microchip web site at
www.microchip.com. Under “Support”, click on
“Customer Change Notification” and follow the
registration instructions.
CUSTOMER SUPP ORT
Users of Microchip products can receive assistance
through several channels:
• Distributor or Representative
• Local Sales Office
• Field Application Engineer (FAE)
• Technical Support
• Development Systems Information Line
Customers should contact their distributor,
representative or field application engineer (FAE) for
support. Local sales offices are also available to help
customers. A listing of sales offices and locations is
included in the back of this document.
Technical suppo rt is avail able throug h the we b site
at: http://microchip.com/support
PIC18F87K22 FAMILY
DS39960C-page 546 2011 Microchip Technology Inc.
READER RESP ONSE
It is our intention to provide you with the best documentation possible to ensure successful use of your Microchip
product. If you wish to provide your comments on organization, clarity, subject matter, and ways in which our
documentation can better serve you, please FAX your comments to the Technical Publications Manager at
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Please list the following information, and use this outline to provide us with your comments about this document.
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DS39960CPIC18F87K22 Family
1. What are the best features of this document?
2. How does this document meet your hardware and software development needs?
3. Do you find the organization of this document easy to follow? If not, why?
4. What additions to the document do you think would enhance the structure and subject?
5. What deletions from the document could be made without affecting the overall usefulness?
6. Is there any incorrect or misleading information (what and where)?
7. How would you improve this document?
2011 Microchip Technology Inc. DS39960C-page 547
PIC18F87K22 FAMILY
PRODUCT IDENTIFICATION SYSTEM
To order or obtain information, e.g., on pricing or delivery, refer to the factory or the listed sales office.
PART NO. X/XX XXX
PatternPackageTemperature
Range
Device
Device(1,2) PIC18F65K22, PIC18F65K22T
PIC18F66K22, PIC18F66K22T
PIC18F67K22, PIC18F67K22T
PIC18F85K22, PIC18F85K22T
PIC18F86K22, PIC18F86K22T
PIC18F87K22, PIC18F87K22T
Temperature Range I = -40C to +85C (Industrial)
Package PT = TQFP (Plastic Thin Quad Flatpack)
MR = QFN (Plastic Quad Flat)
Pattern QTP, SQTP, Code or Special Requirements
(blank otherwise)
Examples:
a) PIC18F87K22-I/PT 301 = Industrial temperature,
TQFP package, QTP pattern #301.
b) PIC18F87K22T-I/PT = Tape and reel, Industrial
temperature, TQFP package
Note 1: F = Standard Voltage Range
2: T = In tape and reel PLCC and
TQFP packages only
3: RSL = Silicon Revision A3
DS39960C-page 548 2011 Microchip Technology Inc.
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02/18/11
