PIC16F8X 18-pin Flash/EEPROM 8-Bit Microcontrollers Devices Included in this Data Sheet: Pin Diagrams PIC16F83 PIC16F84 PIC16CR83 PIC16CR84 Extended voltage range devices available (PIC16LF8X, PIC16LCR8X) PDIP, SOIC High Performance RISC CPU Features: * Only 35 single word instructions to learn * All instructions single cycle except for program branches which are two-cycle * Operating speed: DC - 10 MHz clock input DC - 400 ns instruction cycle Device Program Memory (words) Data Data RAM EEPROM (bytes) (bytes) Max. Freq (MHz) PIC16F83 512 Flash 36 64 PIC16F84 1 K Flash 68 64 10 PIC16CR83 512 ROM 36 64 10 PIC16CR84 1 K ROM 68 64 10 * * * * * * 10 14-bit wide instructions 8-bit wide data path 15 special function hardware registers Eight-level deep hardware stack Direct, indirect and relative addressing modes Four interrupt sources: - External RB0/INT pin - TMR0 timer overflow - PORTB<7:4> interrupt on change - Data EEPROM write complete * 1000 erase/write cycles Flash program memory * 10,000,000 erase/write cycles EEPROM data memory * EEPROM Data Retention > 40 years Peripheral Features: RA2 *1 18 RA1 RA3 2 17 RA0 RA4/T0CKI 3 16 OSC1/CLKIN MCLR 4 15 OSC2/CLKOUT VSS 5 14 VDD RB0/INT 6 13 RB7 RB1 7 12 RB6 RB2 8 11 RB5 RB3 9 10 RB4 PIC16F8X PIC16CR8X * * * * * Special Microcontroller Features: * In-Circuit Serial Programming (ICSPTM) - via two pins (ROM devices support only Data EEPROM programming) * Power-on Reset (POR) * Power-up Timer (PWRT) * Oscillator Start-up Timer (OST) * Watchdog Timer (WDT) with its own on-chip RC oscillator for reliable operation * Code-protection * Power saving SLEEP mode * Selectable oscillator options CMOS Flash/EEPROM Technology: * Low-power, high-speed technology * Fully static design * Wide operating voltage range: - Commercial: 2.0V to 6.0V - Industrial: 2.0V to 6.0V * Low power consumption: - < 2 mA typical @ 5V, 4 MHz - 15 A typical @ 2V, 32 kHz - < 1 A typical standby current @ 2V * 13 I/O pins with individual direction control * High current sink/source for direct LED drive - 25 mA sink max. per pin - 20 mA source max. per pin * TMR0: 8-bit timer/counter with 8-bit programmable prescaler 1998 Microchip Technology Inc. DS30430C-page 1 PIC16F8X Table of Contents 1.0 General Description ...................................................................................................................................................................... 3 2.0 PIC16F8X Device Varieties .......................................................................................................................................................... 5 3.0 Architectural Overview.................................................................................................................................................................. 7 4.0 Memory Organization ................................................................................................................................................................. 11 5.0 I/O Ports...................................................................................................................................................................................... 21 6.0 Timer0 Module and TMR0 Register............................................................................................................................................ 27 7.0 Data EEPROM Memory.............................................................................................................................................................. 33 8.0 Special Features of the CPU ...................................................................................................................................................... 37 9.0 Instruction Set Summary ............................................................................................................................................................ 53 10.0 Development Support ................................................................................................................................................................. 69 11.0 Electrical Characteristics for PIC16F83 and PIC16F84.............................................................................................................. 73 12.0 Electrical Characteristics for PIC16CR83 and PIC16CR84........................................................................................................ 85 13.0 DC & AC Characteristics Graphs/Tables.................................................................................................................................... 97 14.0 Packaging Information .............................................................................................................................................................. 109 Appendix A: Feature Improvements - From PIC16C5X To PIC16F8X .......................................................................................... 113 Appendix B: Code Compatibility - from PIC16C5X to PIC16F8X.................................................................................................. 113 Appendix C: What's New In This Data Sheet ................................................................................................................................. 114 Appendix D: What's Changed In This Data Sheet ......................................................................................................................... 114 Appendix E: Conversion Considerations - PIC16C84 to PIC16F83/F84 And PIC16CR83/CR84.................................................. 115 Index ................................................................................................................................................................................................. 117 On-Line Support................................................................................................................................................................................. 119 Reader Response .............................................................................................................................................................................. 120 PIC16F8X Product Identification System ........................................................................................................................................... 121 Sales and Support.............................................................................................................................................................................. 121 To Our Valued Customers We constantly strive to improve the quality of all our products and documentation. We have spent a great deal of time to ensure that these documents are correct. However, we realize that we may have missed a few things. If you find any information that is missing or appears in error, please use the reader response form in the back of this data sheet to inform us. We appreciate your assistance in making this a better document. DS30430C-page 2 1998 Microchip Technology Inc. PIC16F8X 1.0 GENERAL DESCRIPTION The PIC16F8X is a group in the PIC16CXX family of low-cost, high-performance, CMOS, fully-static, 8-bit microcontrollers. This group contains the following devices: * * * * PIC16F83 PIC16F84 PIC16CR83 PIC16CR84 All PICmicroTM microcontrollers employ an advanced RISC architecture. PIC16F8X devices have enhanced core features, eight-level deep stack, and multiple internal and external interrupt sources. The separate instruction and data buses of the Harvard architecture allow a 14-bit wide instruction word with a separate 8-bit wide data bus. The two stage instruction pipeline allows all instructions to execute in a single cycle, except for program branches (which require two cycles). A total of 35 instructions (reduced instruction set) are available. Additionally, a large register set is used to achieve a very high performance level. PIC16F8X microcontrollers typically achieve a 2:1 code compression and up to a 4:1 speed improvement (at 20 MHz) over other 8-bit microcontrollers in their class. The PIC16F8X has up to 68 bytes of RAM, 64 bytes of Data EEPROM memory, and 13 I/O pins. A timer/ counter is also available. The PIC16CXX family has special features to reduce external components, thus reducing cost, enhancing system reliability and reducing power consumption. There are four oscillator options, of which the single pin RC oscillator provides a low-cost solution, the LP oscillator minimizes power consumption, XT is a standard crystal, and the HS is for High Speed crystals. The SLEEP (power-down) mode offers power saving. The user can wake the chip from sleep through several external and internal interrupts and resets. A highly reliable Watchdog Timer with its own on-chip RC oscillator provides protection against software lockup. Table 1-1 lists the features of the PIC16F8X. A simplified block diagram of the PIC16F8X is shown in Figure 3-1. The PIC16F8X fits perfectly in applications ranging from high speed automotive and appliance motor control to low-power remote sensors, electronic locks, security devices and smart cards. The Flash/EEPROM technology makes customization of application programs (transmitter codes, motor speeds, receiver frequencies, security codes, etc.) extremely fast and convenient. The small footprint packages make this microcontroller series perfect for all applications with space limitations. Low-cost, low-power, high performance, ease-of-use and I/O flexibility make the PIC16F8X very versatile even in areas where no microcontroller use has been considered before (e.g., timer functions; serial communication; capture, compare and PWM functions; and co-processor applications). The serial in-system programming feature (via two pins) offers flexibility of customizing the product after complete assembly and testing. This feature can be used to serialize a product, store calibration data, or program the device with the current firmware before shipping. 1.1 Family and Upward Compatibility Those users familiar with the PIC16C5X family of microcontrollers will realize that this is an enhanced version of the PIC16C5X architecture. Please refer to Appendix A for a detailed list of enhancements. Code written for PIC16C5X devices can be easily ported to PIC16F8X devices (Appendix B). 1.2 Development Support The PIC16CXX family is supported by a full-featured macro assembler, a software simulator, an in-circuit emulator, a low-cost development programmer and a full-featured programmer. A "C" compiler and fuzzy logic support tools are also available. The devices with Flash program memory allow the same device package to be used for prototyping and production. In-circuit reprogrammability allows the code to be updated without the device being removed from the end application. This is useful in the development of many applications where the device may not be easily accessible, but the prototypes may require code updates. This is also useful for remote applications where the code may need to be updated (such as rate information). 1998 Microchip Technology Inc. DS30430C-page 3 PIC16F8X TABLE 1-1 PIC16F8X FAMILY OF DEVICES PIC16F83 Clock Memory Maximum Frequency of Operation (MHz) PIC16CR83 10 PIC16F84 10 PIC16CR84 10 Flash Program Memory 512 -- 1K -- EEPROM Program Memory -- -- -- -- ROM Program Memory -- 512 -- 1K Data Memory (bytes) 36 36 68 68 Data EEPROM (bytes) 64 64 64 64 TMR0 TMR0 TMR0 TMR0 Interrupt Sources 4 4 4 4 I/O Pins 13 13 13 13 Voltage Range (Volts) 2.0-6.0 2.0-6.0 2.0-6.0 2.0-6.0 Packages 18-pin DIP, SOIC 18-pin DIP, SOIC 18-pin DIP, SOIC 18-pin DIP, SOIC Peripherals Timer Module(s) Features 10 All PICmicroTM Family devices have Power-on Reset, selectable Watchdog Timer, selectable code protect and high I/O current capability. All PIC16F8X Family devices use serial programming with clock pin RB6 and data pin RB7. DS30430C-page 4 1998 Microchip Technology Inc. PIC16F8X 2.0 PIC16F8X DEVICE VARIETIES A variety of frequency ranges and packaging options are available. Depending on application and production requirements the proper device option can be selected using the information in this section. When placing orders, please use the "PIC16F8X Product Identification System" at the back of this data sheet to specify the correct part number. There are four device "types" as indicated in the device number. 1. 2. 3. 4. F, as in PIC16F84. These devices have Flash program memory and operate over the standard voltage range. LF, as in PIC16LF84. These devices have Flash program memory and operate over an extended voltage range. CR, as in PIC16CR83. These devices have ROM program memory and operate over the standard voltage range. LCR, as in PIC16LCR84. These devices have ROM program memory and operate over an extended voltage range. When discussing memory maps and other architectural features, the use of F and CR also implies the LF and LCR versions. 2.1 2.3 Serialized Quick-TurnaroundProduction (SQTP SM ) Devices Microchip offers the unique programming service where a few user-defined locations in each device are programmed with different serial numbers. The serial numbers may be random, pseudo-random or sequential. Serial programming allows each device to have a unique number which can serve as an entry-code, password or ID number. For information on submitting a SQTP code, please contact your Microchip Regional Sales Office. 2.4 ROM Devices Some of Microchip's devices have a corresponding device where the program memory is a ROM. These devices give a cost savings over Microchip's traditional user programmed devices (EPROM, EEPROM). ROM devices (PIC16CR8X) do not allow serialization information in the program memory space. The user may program this information into the Data EEPROM. For information on submitting a ROM code, please contact your Microchip Regional Sales Office. Flash Devices These devices are offered in the lower cost plastic package, even though the device can be erased and reprogrammed. This allows the same device to be used for prototype development and pilot programs as well as production. A further advantage of the electrically-erasable Flash version is that it can be erased and reprogrammed incircuit, or by device programmers, such as Microchip's PICSTART(R) Plus or PRO MATE(R) II programmers. 2.2 Quick-Turnaround-Production (QTP) Devices Microchip offers a QTP Programming Service for factory production orders. This service is made available for users who choose not to program a medium to high quantity of units and whose code patterns have stabilized. The devices have all Flash locations and configuration options already programmed by the factory. Certain code and prototype verification procedures do apply before production shipments are available. For information on submitting a QTP code, please contact your Microchip Regional Sales Office. 1998 Microchip Technology Inc. DS30430C-page 5 PIC16F8X NOTES: DS30430C-page 6 1998 Microchip Technology Inc. PIC16F8X 3.0 ARCHITECTURAL OVERVIEW The high performance of the PIC16CXX family can be attributed to a number of architectural features commonly found in RISC microprocessors. To begin with, the PIC16CXX uses a Harvard architecture. This architecture has the program and data accessed from separate memories. So the device has a program memory bus and a data memory bus. This improves bandwidth over traditional von Neumann architecture where program and data are fetched from the same memory (accesses over the same bus). Separating program and data memory further allows instructions to be sized differently than the 8-bit wide data word. PIC16CXX opcodes are 14-bits wide, enabling single word instructions. The full 14-bit wide program memory bus fetches a 14-bit instruction in a single cycle. A twostage pipeline overlaps fetch and execution of instructions (Example 3-1). Consequently, all instructions execute in a single cycle except for program branches. The PIC16F83 and PIC16CR83 address 512 x 14 of program memory, and the PIC16F84 and PIC16CR84 address 1K x 14 program memory. All program memory is internal. The PIC16CXX can directly or indirectly address its register files or data memory. All special function registers including the program counter are mapped in the data memory. An orthogonal (symmetrical) instruction set makes it possible to carry out any operation on any register using any addressing mode. This symmetrical nature and lack of `special optimal situations' make programming with the PIC16CXX simple yet efficient. In addition, the learning curve is reduced significantly. 1998 Microchip Technology Inc. DS30430C-page 7 PIC16F8X PIC16CXX devices contain an 8-bit ALU and working register. The ALU is a general purpose arithmetic unit. It performs arithmetic and Boolean functions between data in the working register and any register file. The W register is an 8-bit working register used for ALU operations. It is not an addressable register. Depending on the instruction executed, the ALU may affect the values of the Carry (C), Digit Carry (DC), and Zero (Z) bits in the STATUS register. The C and DC bits operate as a borrow and digit borrow out bit, respectively, in subtraction. See the SUBLW and SUBWF instructions for examples. The ALU is 8-bits wide and capable of addition, subtraction, shift and logical operations. Unless otherwise mentioned, arithmetic operations are two's complement in nature. In two-operand instructions, typically one operand is the working register (W register), and the other operand is a file register or an immediate constant. In single operand instructions, the operand is either the W register or a file register. FIGURE 3-1: PIC16F8X BLOCK DIAGRAM Data Bus 13 8 Program Counter Flash/ROM Program Memory PIC16F83/CR83 512 x 14 PIC16F84/CR84 1K x 14 Program Bus A simplified block diagram for the PIC16F8X is shown in Figure 3-1, its corresponding pin description is shown in Table 3-1. 8 Level Stack (13-bit) 14 EEPROM Data Memory RAM File Registers PIC16F83/CR83 36 x 8 PIC16F84/CR84 68 x 8 7 EEDATA RAM Addr EEPROM Data Memory 64 x 8 EEADR Addr Mux Instruction reg 7 Direct Addr 5 TMR0 Indirect Addr FSR reg RA4/T0CKI STATUS reg 8 MUX Power-up Timer Instruction Decode & Control Timing Generation Oscillator Start-up Timer 8 ALU Power-on Reset Watchdog Timer I/O Ports RA3:RA0 W reg RB7:RB1 RB0/INT OSC2/CLKOUT OSC1/CLKIN DS30430C-page 8 MCLR VDD, VSS 1998 Microchip Technology Inc. PIC16F8X TABLE 3-1 PIC16F8X PINOUT DESCRIPTION DIP No. SOIC No. I/O/P Type OSC1/CLKIN 16 16 I OSC2/CLKOUT 15 15 O -- Oscillator crystal output. Connects to crystal or resonator in crystal oscillator mode. In RC mode, OSC2 pin outputs CLKOUT which has 1/4 the frequency of OSC1, and denotes the instruction cycle rate. MCLR 4 4 I/P ST Master clear (reset) input/programming voltage input. This pin is an active low reset to the device. Pin Name Buffer Type Description ST/CMOS (3) Oscillator crystal input/external clock source input. PORTA is a bi-directional I/O port. RA0 17 17 I/O TTL RA1 18 18 I/O TTL RA2 1 1 I/O TTL RA3 2 2 I/O TTL RA4/T0CKI 3 3 I/O ST Can also be selected to be the clock input to the TMR0 timer/ counter. Output is open drain type. PORTB is a bi-directional I/O port. PORTB can be software programmed for internal weak pull-up on all inputs. RB0/INT 6 6 I/O TTL/ST (1) RB1 7 7 I/O TTL RB2 8 8 I/O TTL RB0/INT can also be selected as an external interrupt pin. RB3 9 9 I/O TTL RB4 10 10 I/O TTL Interrupt on change pin. RB5 11 11 I/O TTL Interrupt on change pin. RB6 12 12 I/O TTL/ST (2) (2) TTL/ST Interrupt on change pin. Serial programming clock. Interrupt on change pin. Serial programming data. RB7 13 13 I/O VSS 5 5 P -- Ground reference for logic and I/O pins. VDD 14 14 P -- Positive supply for logic and I/O pins. Legend: I= input O = output I/O = Input/Output P = power -- = Not used TTL = TTL input ST = Schmitt Trigger input Note 1: This buffer is a Schmitt Trigger input when configured as the external interrupt. 2: This buffer is a Schmitt Trigger input when used in serial programming mode. 3: This buffer is a Schmitt Trigger input when configured in RC oscillator mode and a CMOS input otherwise. 1998 Microchip Technology Inc. DS30430C-page 9 PIC16F8X 3.1 Clocking Scheme/Instruction Cycle 3.2 The clock input (from OSC1) is internally divided by four to generate four non-overlapping quadrature clocks namely Q1, Q2, Q3 and Q4. Internally, the program counter (PC) is incremented every Q1, the instruction is fetched from the program memory and latched into the instruction register in Q4. The instruction is decoded and executed during the following Q1 through Q4. The clocks and instruction execution flow is shown in Figure 3-2. Instruction Flow/Pipelining An "Instruction Cycle" consists of four Q cycles (Q1, Q2, Q3 and Q4). The instruction fetch and execute are pipelined such that fetch takes one instruction cycle while decode and execute takes another instruction cycle. However, due to the pipelining, each instruction effectively executes in one cycle. If an instruction causes the program counter to change (e.g., GOTO) then two cycles are required to complete the instruction (Example 3-1). 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" 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 3-2: CLOCK/INSTRUCTION CYCLE Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 OSC1 Q1 Q2 Internal phase clock Q3 Q4 PC PC OSC2/CLKOUT (RC mode) EXAMPLE 3-1: Fetch INST (PC) Execute INST (PC-1) PC+2 Fetch INST (PC+1) Execute INST (PC) Fetch INST (PC+2) Execute INST (PC+1) INSTRUCTION PIPELINE FLOW 1. MOVLW 55h 2. MOVWF PORTB 3. CALL SUB_1 4. BSF PC+1 PORTA, BIT3 Fetch 1 Execute 1 Fetch 2 Execute 2 Fetch 3 Execute 3 Fetch 4 Flush Fetch SUB_1 Execute SUB_1 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. DS30430C-page 10 1998 Microchip Technology Inc. PIC16F8X MEMORY ORGANIZATION There are two memory blocks in the PIC16F8X. These are the program memory and the data memory. Each block has its own bus, so that access to each block can occur during the same oscillator cycle. The data memory can further be broken down into the general purpose RAM and the Special Function Registers (SFRs). The operation of the SFRs that control the "core" are described here. The SFRs used to control the peripheral modules are described in the section discussing each individual peripheral module. The data memory area also contains the data EEPROM memory. This memory is not directly mapped into the data memory, but is indirectly mapped. That is, an indirect address pointer specifies the address of the data EEPROM memory to read/write. The 64 bytes of data EEPROM memory have the address range 0h-3Fh. More details on the EEPROM memory can be found in Section 7.0. 4.1 FIGURE 4-1: PROGRAM MEMORY MAP AND STACK - PIC16F83/CR83 PC<12:0> 13 CALL, RETURN RETFIE, RETLW Stack Level 1 * * * Stack Level 8 User Memory Space 4.0 Reset Vector 0000h Peripheral Interrupt Vector 0004h 1FFh Program Memory Organization The PIC16FXX has a 13-bit program counter capable of addressing an 8K x 14 program memory space. For the PIC16F83 and PIC16CR83, the first 512 x 14 (0000h-01FFh) are physically implemented (Figure 4-1). For the PIC16F84 and PIC16CR84, the first 1K x 14 (0000h-03FFh) are physically implemented (Figure 4-2). Accessing a location above the physically implemented address will cause a wraparound. For example, for the PIC16F84 locations 20h, 420h, 820h, C20h, 1020h, 1420h, 1820h, and 1C20h will be the same instruction. 1FFFh FIGURE 4-2: PROGRAM MEMORY MAP AND STACK - PIC16F84/CR84 PC<12:0> 13 CALL, RETURN RETFIE, RETLW Stack Level 1 * * * Stack Level 8 Reset Vector 0000h Peripheral Interrupt Vector 0004h User Memory Space The reset vector is at 0000h and the interrupt vector is at 0004h. 3FFh 1FFFh 1998 Microchip Technology Inc. DS30430C-page 11 PIC16F8X 4.2 Data Memory Organization 4.2.1 GENERAL PURPOSE REGISTER FILE The data memory is partitioned into two areas. The first is the Special Function Registers (SFR) area, while the second is the General Purpose Registers (GPR) area. The SFRs control the operation of the device. All devices have some amount of General Purpose Register (GPR) area. Each GPR is 8 bits wide and is accessed either directly or indirectly through the FSR (Section 4.5). Portions of data memory are banked. This is for both the SFR area and the GPR area. The GPR area is banked to allow greater than 116 bytes of general purpose RAM. The banked areas of the SFR are for the registers that control the peripheral functions. Banking requires the use of control bits for bank selection. These control bits are located in the STATUS Register. Figure 4-1 and Figure 4-2 show the data memory map organization. The GPR addresses in bank 1 are mapped to addresses in bank 0. As an example, addressing location 0Ch or 8Ch will access the same GPR. Instructions MOVWF and MOVF can move values from the W register to any location in the register file ("F"), and vice-versa. The special function registers can be classified into two sets, core and peripheral. Those associated with the core functions are described in this section. Those related to the operation of the peripheral features are described in the section for that specific feature. The entire data memory can be accessed either directly using the absolute address of each register file or indirectly through the File Select Register (FSR) (Section 4.5). Indirect addressing uses the present value of the RP1:RP0 bits for access into the banked areas of data memory. 4.2.2 SPECIAL FUNCTION REGISTERS The Special Function Registers (Figure 4-1, Figure 4-2 and Table 4-1) are used by the CPU and Peripheral functions to control the device operation. These registers are static RAM. Data memory is partitioned into two banks which contain the general purpose registers and the special function registers. Bank 0 is selected by clearing the RP0 bit (STATUS<5>). Setting the RP0 bit selects Bank 1. Each Bank extends up to 7Fh (128 bytes). The first twelve locations of each Bank are reserved for the Special Function Registers. The remainder are General Purpose Registers implemented as static RAM. DS30430C-page 12 1998 Microchip Technology Inc. PIC16F8X FIGURE 4-1: REGISTER FILE MAP PIC16F83/CR83 File Address FIGURE 4-2: REGISTER FILE MAP PIC16F84/CR84 File Address File Address 80h 00h Indirect addr.(1) OPTION 81h 01h TMR0 OPTION 81h PCL 82h 02h PCL PCL 82h STATUS STATUS 83h 03h STATUS STATUS 83h FSR FSR 84h 04h FSR FSR 84h 05h PORTA TRISA 85h 05h PORTA TRISA 85h 06h PORTB TRISB 86h 06h PORTB TRISB 86h 87h 07h 08h EEDATA EECON1 88h 08h EEDATA EECON1 88h 09h EEADR EECON2(1) 89h 09h EEADR EECON2(1) 89h 0Ah PCLATH PCLATH 8Ah 0Ah PCLATH PCLATH 8Ah 0Bh INTCON INTCON 8Bh 0Bh INTCON INTCON 8Bh 8Ch 0Ch 00h Indirect addr.(1) 01h TMR0 02h PCL 03h 04h Indirect addr.(1) 07h 0Ch 36 General Purpose registers (SRAM) Mapped (accesses) in Bank 0 2Fh 30h File Address 8Ch Mapped (accesses) in Bank 0 4Fh 50h 7Fh FFh Bank 0 Bank 1 Unimplemented data memory location; read as '0'. Note 1: Not a physical register. 1998 Microchip Technology Inc. 80h 87h 68 General Purpose registers (SRAM) AFh B0h Indirect addr.(1) CFh D0h 7Fh FFh Bank 0 Bank 1 Unimplemented data memory location; read as '0'. Note 1: Not a physical register. DS30430C-page 13 PIC16F8X TABLE 4-1 Address REGISTER FILE SUMMARY Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Value on Power-on Reset Value on all other resets (Note3) Bank 0 00h INDF Uses contents of FSR to address data memory (not a physical register) ---- ---- ---- ---- 01h TMR0 8-bit real-time clock/counter xxxx xxxx uuuu uuuu 02h PCL Low order 8 bits of the Program Counter (PC) 0000 0000 0000 0000 (2) IRP RP1 TO RP0 PD Z DC 03h STATUS 04h FSR 05h PORTA -- -- -- RA4/T0CKI RA3 RA2 RA1 06h PORTB RB7 RB6 RB5 RB4 RB3 RB2 RB1 07h C 0001 1xxx 000q quuu xxxx xxxx uuuu uuuu RA0 ---x xxxx ---u uuuu RB0/INT xxxx xxxx uuuu uuuu Unimplemented location, read as '0' ---- ---- ---- ---- Indirect data memory address pointer 0 08h EEDATA EEPROM data register xxxx xxxx uuuu uuuu 09h EEADR EEPROM address register xxxx xxxx uuuu uuuu 0Ah PCLATH -- -- -- ---0 0000 ---0 0000 0Bh INTCON GIE EEIE T0IE 0000 000x 0000 000u ---- ---- ---- ---- 1111 1111 1111 1111 0000 0000 0000 0000 Write buffer for upper 5 bits of the PC (1) INTE RBIE T0IF INTF RBIF Bank 1 80h INDF 81h OPTION_ REG 82h PCL 83h STATUS (2) 84h FSR 85h TRISA 86h TRISB 87h 88h EECON1 Uses contents of FSR to address data memory (not a physical register) RBPU INTEDG T0CS T0SE PSA PS2 PS1 PS0 Low order 8 bits of Program Counter (PC) IRP RP1 RP0 TO PD Z DC C Indirect data memory address pointer 0 -- -- -- PORTA data direction register 0001 1xxx 000q quuu xxxx xxxx uuuu uuuu ---1 1111 ---1 1111 PORTB data direction register 1111 1111 1111 1111 Unimplemented location, read as '0' ---- ---- ---- ---- ---0 x000 ---0 q000 -- -- -- 89h EECON2 0Ah PCLATH -- -- -- 0Bh INTCON GIE EEIE T0IE EEIF WRERR WREN WR RD EEPROM control register 2 (not a physical register) Write buffer for upper 5 bits of the PC (1) INTE RBIE T0IF INTF RBIF ---- ---- ---- ---- ---0 0000 ---0 0000 0000 000x 0000 000u Legend: x = unknown, u = unchanged. - = unimplemented read as '0', q = value depends on condition. Note 1: The upper byte of the program counter is not directly accessible. PCLATH is a slave register for PC<12:8>. The contents of PCLATH can be transferred to the upper byte of the program counter, but the contents of PC<12:8> is never transferred to PCLATH. 2: The TO and PD status bits in the STATUS register are not affected by a MCLR reset. 3: Other (non power-up) resets include: external reset through MCLR and the Watchdog Timer Reset. DS30430C-page 14 1998 Microchip Technology Inc. PIC16F8X 4.2.2.1 STATUS REGISTER The STATUS register contains the arithmetic status of the ALU, the RESET status and the bank select bit for data memory. As with any register, the STATUS register can be the destination for any instruction. If the STATUS register is the destination for an instruction that affects the Z, DC or C bits, then the write to these three bits is disabled. These bits are set or cleared according to device logic. Furthermore, the TO and PD bits are not writable. Therefore, the result of an instruction with the STATUS register as destination may be different than intended. For example, CLRF STATUS will clear the upper-three bits and set the Z bit. This leaves the STATUS register as 000u u1uu (where u = unchanged). FIGURE 4-1: R/W-0 IRP Only the BCF, BSF, SWAPF and MOVWF instructions should be used to alter the STATUS register (Table 9-2) because these instructions do not affect any status bit. Note 1: The IRP and RP1 bits (STATUS<7:6>) are not used by the PIC16F8X and should be programmed as cleared. Use of these bits as general purpose R/W bits is NOT recommended, since this may affect upward compatibility with future products. Note 2: The C and DC bits operate as a borrow and digit borrow out bit, respectively, in subtraction. See the SUBLW and SUBWF instructions for examples. Note 3: When the STATUS register is the destination for an instruction that affects the Z, DC or C bits, then the write to these three bits is disabled. The specified bit(s) will be updated according to device logic STATUS REGISTER (ADDRESS 03h, 83h) R/W-0 RP1 R/W-0 RP0 R-1 TO R-1 PD R/W-x Z R/W-x DC bit7 bit 7: R/W-x C bit0 R = Readable bit W = Writable bit U = Unimplemented bit, read as `0' - n = Value at POR reset IRP: Register Bank Select bit (used for indirect addressing) 0 = Bank 0, 1 (00h - FFh) 1 = Bank 2, 3 (100h - 1FFh) The IRP bit is not used by the PIC16F8X. IRP should be maintained clear. bit 6-5: RP1:RP0: Register Bank Select bits (used for direct addressing) 00 = Bank 0 (00h - 7Fh) 01 = Bank 1 (80h - FFh) 10 = Bank 2 (100h - 17Fh) 11 = Bank 3 (180h - 1FFh) Each bank is 128 bytes. Only bit RP0 is used by the PIC16F8X. RP1 should be maintained clear. bit 4: TO: Time-out bit 1 = After power-up, CLRWDT instruction, or SLEEP instruction 0 = A WDT time-out occurred bit 3: PD: Power-down bit 1 = After power-up or by the CLRWDT instruction 0 = By execution of the SLEEP instruction 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 (for ADDWF and ADDLW instructions) (For borrow the polarity is reversed) 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 (for ADDWF and ADDLW 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:For borrow the polarity is reversed. A subtraction is executed by adding the two'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. 1998 Microchip Technology Inc. DS30430C-page 15 PIC16F8X 4.2.2.2 OPTION_REG REGISTER Note: The OPTION_REG register is a readable and writable register which contains various control bits to configure the TMR0/WDT prescaler, the external INT interrupt, TMR0, and the weak pull-ups on PORTB. FIGURE 4-1: When the prescaler is assigned to the WDT (PSA = '1'), TMR0 has a 1:1 prescaler assignment. OPTION_REG REGISTER (ADDRESS 81h) 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 INTEDG T0CS T0SE PSA PS2 PS1 PS0 bit7 bit0 bit 7: RBPU: PORTB Pull-up Enable bit 1 = PORTB pull-ups are disabled 0 = PORTB pull-ups are enabled (by individual port latch values) bit 6: INTEDG: Interrupt Edge Select bit 1 = Interrupt on rising edge of RB0/INT pin 0 = Interrupt on falling edge of RB0/INT pin bit 5: T0CS: TMR0 Clock Source Select bit 1 = Transition on RA4/T0CKI pin 0 = Internal instruction cycle clock (CLKOUT) bit 4: T0SE: TMR0 Source Edge Select bit 1 = Increment on high-to-low transition on RA4/T0CKI pin 0 = Increment on low-to-high transition on RA4/T0CKI pin bit 3: PSA: Prescaler Assignment bit 1 = Prescaler assigned to the WDT 0 = Prescaler assigned to TMR0 R = Readable bit W = Writable bit U = Unimplemented bit, read as `0' - n = Value at POR reset bit 2-0: PS2:PS0: Prescaler Rate Select bits Bit Value 000 001 010 011 100 101 110 111 DS30430C-page 16 TMR0 Rate 1:2 1:4 1:8 1 : 16 1 : 32 1 : 64 1 : 128 1 : 256 WDT Rate 1:1 1:2 1:4 1:8 1 : 16 1 : 32 1 : 64 1 : 128 1998 Microchip Technology Inc. PIC16F8X 4.2.2.3 INTCON REGISTER Note: The INTCON register is a readable and writable register which contains the various enable bits for all interrupt sources. FIGURE 4-1: Interrupt flag bits get set when an interrupt condition occurs regardless of the state of its corresponding enable bit or the global enable bit, GIE (INTCON<7>). INTCON REGISTER (ADDRESS 0Bh, 8Bh) 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 EEIE T0IE INTE RBIE T0IF INTF RBIF bit7 bit 7: bit0 R = Readable bit W = Writable bit U = Unimplemented bit, read as `0' - n = Value at POR reset GIE: Global Interrupt Enable bit 1 = Enables all un-masked interrupts 0 = Disables all interrupts Note: For the operation of the interrupt structure, please refer to Section 8.5. bit 6: EEIE: EE Write Complete Interrupt Enable bit 1 = Enables the EE write complete interrupt 0 = Disables the EE write complete interrupt bit 5: T0IE: TMR0 Overflow Interrupt Enable bit 1 = Enables the TMR0 interrupt 0 = Disables the TMR0 interrupt bit 4: INTE: RB0/INT Interrupt Enable bit 1 = Enables the RB0/INT interrupt 0 = Disables the RB0/INT 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: T0IF: TMR0 overflow interrupt flag bit 1 = TMR0 has overflowed (must be cleared in software) 0 = TMR0 did not overflow bit 1: INTF: RB0/INT Interrupt Flag bit 1 = The RB0/INT interrupt occurred 0 = The RB0/INT interrupt did not occur bit 0: RBIF: RB Port Change Interrupt Flag bit 1 = When at least one of the RB7:RB4 pins changed state (must be cleared in software) 0 = None of the RB7:RB4 pins have changed state 1998 Microchip Technology Inc. DS30430C-page 17 PIC16F8X 4.3 Program Counter: PCL and PCLATH The Program Counter (PC) is 13-bits wide. The low byte is the PCL register, which is a readable and writable register. The high byte of the PC (PC<12:8>) is not directly readable nor writable and comes from the PCLATH register. The PCLATH (PC latch high) register is a holding register for PC<12:8>. The contents of PCLATH are transferred to the upper byte of the program counter when the PC is loaded with a new value. This occurs during a CALL, GOTO or a write to PCL. The high bits of PC are loaded from PCLATH as shown in Figure 4-1. FIGURE 4-1: LOADING OF PC IN DIFFERENT SITUATIONS PCH 12 PCL 8 7 0 INST with PCL as dest PC 8 PCLATH<4:0> 5 ALU result manipulation of the PCLATH<4:3> is not required for the return instructions (which "pops" the PC from the stack). Note: 4.4 The PIC16F8X ignores the PCLATH<4:3> bits, which are used for program memory pages 1, 2 and 3 (0800h - 1FFFh). The use of PCLATH<4:3> as general purpose R/W bits is not recommended since this may affect upward compatibility with future products. Stack The PIC16FXX has an 8 deep x 13-bit wide hardware stack (Figure 4-1). The stack space is not part of either program or data space and the stack pointer is not readable or writable. The entire 13-bit PC is "pushed" onto the stack when a CALL instruction is executed or an interrupt is acknowledged. The stack is "popped" in the event of a RETURN, RETLW or a RETFIE instruction execution. PCLATH is not affected by a push or a pop operation. PCLATH Note: PCH 12 11 10 PCL 0 8 7 PC GOTO, CALL 2 PCLATH<4:3> 11 Opcode <10:0> PCLATH 4.3.1 COMPUTED GOTO A computed GOTO is accomplished by adding an offset to the program counter (ADDWF PCL). When doing a table read using a computed GOTO method, care should be exercised if the table location crosses a PCL memory boundary (each 256 word block). Refer to the application note "Implementing a Table Read" (AN556). 4.3.2 There are no instruction mnemonics called push or pop. These are actions that occur from the execution of the CALL, RETURN, RETLW, and RETFIE instructions, or the vectoring to an interrupt address. The stack operates as a circular buffer. That is, after the stack has been pushed eight times, the ninth push overwrites the value that was stored from the first push. The tenth push overwrites the second push (and so on). If the stack is effectively popped nine times, the PC value is the same as the value from the first pop. Note: There are no status bits to indicate stack overflow or stack underflow conditions. PROGRAM MEMORY PAGING The PIC16F83 and PIC16CR83 have 512 words of program memory. The PIC16F84 and PIC16CR84 have 1K of program memory. The CALL and GOTO instructions have an 11-bit address range. This 11-bit address range allows a branch within a 2K program memory page size. For future PIC16F8X program memory expansion, there must be another two bits to specify the program memory page. These paging bits come from the PCLATH<4:3> bits (Figure 4-1). When doing a CALL or a GOTO instruction, the user must ensure that these page bits (PCLATH<4:3>) are programmed to the desired program memory page. If a CALL instruction (or interrupt) is executed, the entire 13-bit PC is "pushed" onto the stack (see next section). Therefore, DS30430C-page 18 1998 Microchip Technology Inc. PIC16F8X 4.5 A simple program to clear RAM locations 20h-2Fh using indirect addressing is shown in Example 4-2. Indirect Addressing; INDF and FSR Registers The INDF register is not a physical register. Addressing INDF actually addresses the register whose address is contained in the FSR register (FSR is a pointer). This is indirect addressing. EXAMPLE 4-2: EXAMPLE 4-1: NEXT INDIRECT ADDRESSING * * * * Register file 05 contains the value 10h Register file 06 contains the value 0Ah Load the value 05 into the FSR register A read of the INDF register will return the value of 10h * Increment the value of the FSR register by one (FSR = 06) * A read of the INDF register now will return the value of 0Ah. HOW TO CLEAR RAM USING INDIRECT ADDRESSING movlw movwf clrf incf btfss goto 0x20 FSR INDF FSR FSR,4 NEXT ;initialize pointer ; to RAM ;clear INDF register ;inc pointer ;all done? ;NO, clear next CONTINUE : ;YES, continue An effective 9-bit address is obtained by concatenating the 8-bit FSR register and the IRP bit (STATUS<7>), as shown in Figure 4-1. However, IRP is not used in the PIC16F8X. Reading INDF itself indirectly (FSR = 0) will produce 00h. Writing to the INDF register indirectly results in a no-operation (although STATUS bits may be affected). FIGURE 4-1: DIRECT/INDIRECT ADDRESSING Indirect Addressing Direct Addressing RP1 RP0 bank select 6 from opcode 0 IRP location select 7 bank select 00 01 10 11 not used not used Bank 2 Bank 3 (FSR) 0 location select 00h 00h 0Bh 0Ch Data Memory (3) Addresses map back to Bank 0 2Fh (1) 30h (1) 4Fh (2) 50h (2) 7Fh 7Fh Bank 0 Bank 1 Note 1: PIC16F83 and PIC16CR83 devices. 2: PIC16F84 and PIC16CR84 devices 3: For memory map detail see Figure 4-1. 1998 Microchip Technology Inc. DS30430C-page 19 PIC16F8X NOTES: DS30430C-page 20 1998 Microchip Technology Inc. PIC16F8X 5.0 I/O PORTS EXAMPLE 5-1: INITIALIZING PORTA CLRF PORTA BSF MOVLW STATUS, RP0 0x0F PORTA is a 5-bit wide latch. RA4 is a Schmitt Trigger input and an open drain output. All other RA port pins have TTL input levels and full CMOS output drivers. All pins have data direction bits (TRIS registers) which can configure these pins as output or input. MOVWF TRISA Setting a TRISA bit (=1) will make the corresponding PORTA pin an input, i.e., put the corresponding output driver in a hi-impedance mode. Clearing a TRISA bit (=0) will make the corresponding PORTA pin an output, i.e., put the contents of the output latch on the selected pin. FIGURE 5-2: The PIC16F8X has two ports, PORTA and PORTB. Some port pins are multiplexed with an alternate function for other features on the device. 5.1 ; ; ; ; ; ; ; ; ; ; ; PORTA and TRISA Registers Reading the PORTA register reads the status of the pins whereas writing to it will write to the port latch. All write operations are read-modify-write operations. So a write to a port implies that the port pins are first read, then this value is modified and written to the port data latch. Data bus WR PORT Initialize PORTA by setting output data latches Select Bank 1 Value used to initialize data direction Set RA<3:0> as inputs RA4 as outputs TRISA<7:5> are always read as '0'. BLOCK DIAGRAM OF PIN RA4 D Q CK Q N Data Latch VSS WR TRIS The RA4 pin is multiplexed with the TMR0 clock input. D Q CK Q Schmitt Trigger input buffer TRIS Latch FIGURE 5-1: BLOCK DIAGRAM OF PINS RA3:RA0 Data bus RD TRIS D WR Port RA4 pin Q Q VDD CK Q D EN EN P RD PORT Data Latch N D WR TRIS I/O pin Q VSS CK TMR0 clock input Note: I/O pin has protection diodes to VSS only. Q TRIS Latch TTL input buffer RD TRIS Q D EN RD PORT Note: I/O pins have protection diodes to VDD and VSS. 1998 Microchip Technology Inc. DS30430C-page 21 PIC16F8X TABLE 5-1 PORTA FUNCTIONS Name Bit0 Buffer Type RA0 RA1 RA2 RA3 RA4/T0CKI bit0 bit1 bit2 bit3 bit4 TTL TTL TTL TTL ST Function Input/output Input/output Input/output Input/output Input/output or external clock input for TMR0. Output is open drain type. Legend: TTL = TTL input, ST = Schmitt Trigger input TABLE 5-2 Address SUMMARY OF REGISTERS ASSOCIATED WITH PORTA Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 05h PORTA -- -- -- RA4/T0CKI RA3 RA2 85h TRISA -- -- -- TRISA4 TRISA3 TRISA2 Bit 0 Value on Power-on Reset Value on all other resets RA1 RA0 ---x xxxx ---u uuuu TRISA1 TRISA0 ---1 1111 ---1 1111 Bit 1 Legend: x = unknown, u = unchanged, - = unimplemented read as '0'. Shaded cells are unimplemented, read as '0' DS30430C-page 22 1998 Microchip Technology Inc. PIC16F8X 5.2 PORTB and TRISB Registers PORTB is an 8-bit wide bi-directional port. The corresponding data direction register is TRISB. A '1' on any bit in the TRISB register puts the corresponding output driver in a hi-impedance mode. A '0' on any bit in the TRISB register puts the contents of the output latch on the selected pin(s). Each of the PORTB pins have a weak internal pull-up. A single control bit can turn on all the pull-ups. This is done by clearing the RBPU (OPTION_REG<7>) bit. 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 PORTB's pins, RB7:RB4, have an interrupt on change feature. Only pins configured as inputs can cause this interrupt to occur (i.e., any RB7:RB4 pin configured as an output is excluded from the interrupt on change comparison). The pins value in input mode are compared with the old value latched on the last read of PORTB. The "mismatch" outputs of the pins are OR'ed together to generate the RB port change interrupt. FIGURE 5-3: BLOCK DIAGRAM OF PINS RB7:RB4 This interrupt can wake the device from SLEEP. The user, in the interrupt service routine, can clear the interrupt in the following manner: a) b) Read (or write) PORTB. This will end the mismatch condition. Clear flag bit RBIF. A mismatch condition will continue to set the RBIF bit. Reading PORTB will end the mismatch condition, and allow the RBIF bit to be cleared. This interrupt on mismatch feature, together with software configurable pull-ups on these four pins allow easy interface to a key pad and make it possible for wake-up on key-depression (see AN552 in the Embedded Control Handbook). Note 1: For a change on the I/O pin to be recognized, the pulse width must be at least TCY (4/fOSC) wide. 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. FIGURE 5-4: BLOCK DIAGRAM OF PINS RB3:RB0 VDD RBPU(1) VDD RBPU(1) Data bus weak P pull-up Data Latch D WR Port Q I/O pin(2) CK Data bus WR Port WR TRIS WR TRIS Q Data Latch D Q I/O pin(2) CK TRIS Latch D Q TRIS Latch D weak P pull-up TTL Input Buffer CK TTL Input Buffer CK RD TRIS Q Latch RD TRIS Q RD Port D RD Port D EN EN Set RBIF RB0/INT From other RB7:RB4 pins Q Schmitt Trigger Buffer D RD Port Note 1: TRISB = '1' enables weak pull-up (if RBPU = '0' in the OPTION_REG register). EN 2: I/O pins have diode protection to VDD and VSS. RD Port Note 1: TRISB = '1' enables weak pull-up (if RBPU = '0' in the OPTION_REG register). 2: I/O pins have diode protection to VDD and VSS. 1998 Microchip Technology Inc. DS30430C-page 23 PIC16F8X EXAMPLE 5-1: INITIALIZING PORTB CLRF PORTB BSF MOVLW STATUS, RP0 0xCF MOVWF TRISB TABLE 5-3 Name RB0/INT ; ; ; ; ; ; ; ; ; ; Initialize PORTB by setting output data latches Select Bank 1 Value used to initialize data direction Set RB<3:0> as inputs RB<5:4> as outputs RB<7:6> as inputs PORTB FUNCTIONS Bit Buffer Type bit0 Input/output pin or external interrupt input. Internal software programmable weak pull-up. RB1 bit1 TTL Input/output pin. Internal software programmable weak pull-up. RB2 bit2 TTL Input/output pin. Internal software programmable weak pull-up. RB3 bit3 TTL Input/output pin. Internal software programmable weak pull-up. RB4 bit4 TTL Input/output pin (with interrupt on change). Internal software programmable weak pull-up. RB5 bit5 TTL Input/output pin (with interrupt on change). Internal software programmable weak pull-up. Input/output pin (with interrupt on change). Internal software programmable RB6 bit6 TTL/ST(2) weak pull-up. Serial programming clock. Input/output pin (with interrupt on change). Internal software programmable RB7 bit7 TTL/ST(2) weak pull-up. Serial programming data. Legend: TTL = TTL input, ST = Schmitt Trigger. Note 1: This buffer is a Schmitt Trigger input when configured as the external interrupt. 2: This buffer is a Schmitt Trigger input when used in serial programming mode. TABLE 5-4 Address Name TTL/ST I/O Consistency Function (1) SUMMARY OF REGISTERS ASSOCIATED WITH PORTB Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Value on Power-on Reset Value on all other resets uuuu uuuu 06h PORTB RB7 RB6 RB5 RB4 RB3 RB2 RB1 RB0/INT xxxx xxxx 86h TRISB TRISB7 TRISB6 TRISB5 TRISB4 TRISB3 TRISB2 TRISB1 TRISB0 1111 1111 1111 1111 81h OPTION_ REG PS0 1111 1111 1111 1111 RBPU INTEDG T0CS T0SE PSA PS2 PS1 Legend: x = unknown, u = unchanged. Shaded cells are not used by PORTB. DS30430C-page 24 1998 Microchip Technology Inc. PIC16F8X 5.3 I/O Programming Considerations 5.3.1 BI-DIRECTIONAL I/O PORTS 5.3.2 Any instruction which writes, operates internally as a read followed by a write operation. The BCF and BSF instructions, for example, read the register into the CPU, execute the bit operation and write the result back to the register. Caution must be used when these instructions are applied to a port with both inputs and outputs defined. For example, a BSF operation on bit5 of PORTB will cause all eight bits of PORTB to be read into the CPU. Then the BSF operation takes place on bit5 and PORTB is written to the output latches. If another bit of PORTB is used as a bi-directional I/O pin (i.e., bit0) and it is defined as an input at this time, the input signal present on the pin itself would be read into the CPU and rewritten to the data latch of this particular pin, overwriting the previous content. As long as the pin stays in the input mode, no problem occurs. However, if bit0 is switched into output mode later on, the content of the data latch is unknown. Reading the port register, reads the values of the port pins. Writing to the port register writes the value to the port latch. When using read-modify-write instructions (i.e., BCF, BSF, etc.) on a port, the value of the port pins is read, the desired operation is done to this value, and this value is then written to the port latch. A pin actively outputting a Low or High should not be driven from external devices at the same time in order to change the level on this pin ("wired-or", "wired-and"). The resulting high output current may damage the chip. FIGURE 5-5: The actual write to an I/O port happens at the end of an instruction cycle, whereas for reading, the data must be valid at the beginning of the instruction cycle (Figure 5-5). Therefore, care must be exercised if a write followed by a read operation is carried out on the same I/O port. The sequence of instructions should be such that the pin voltage stabilizes (load dependent) before the next instruction which causes that file to be read into the CPU is executed. Otherwise, the previous state of that pin may be read into the CPU rather than the new state. When in doubt, it is better to separate these instructions with a NOP or another instruction not accessing this I/O port. Example 5-1 shows the effect of two sequential read-modify-write instructions (e.g., BCF, BSF, etc.) on an I/O port. EXAMPLE 5-1: READ-MODIFY-WRITE INSTRUCTIONS ON AN I/O PORT ;Initial PORT settings: PORTB<7:4> Inputs ; PORTB<3:0> Outputs ;PORTB<7:6> have external pull-ups and are ;not connected to other circuitry ; ; PORT latch PORT pins ; ---------- --------BCF PORTB, 7 ; 01pp ppp 11pp ppp BCF PORTB, 6 ; 10pp ppp 11pp ppp BSF STATUS, RP0 ; BCF TRISB, 7 ; 10pp ppp 11pp ppp BCF TRISB, 6 ; 10pp ppp 10pp ppp ; ;Note that the user may have expected the ;pin values to be 00pp ppp. The 2nd BCF ;caused RB7 to be latched as the pin value ;(high). SUCCESSIVE I/O OPERATION Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 PC Instruction fetched SUCCESSIVE OPERATIONS ON I/O PORTS PC PC + 1 MOVWF PORTB MOVF PORTB,W write to PORTB Q1 Q2 Q3 Q4 PC + 2 PC + 3 NOP NOP This example shows a write to PORTB followed by a read from PORTB. Note that: data setup time = (0.25TCY - TPD) RB7:RB0 where TCY = instruction cycle TPD = propagation delay Port pin sampled here TPD Instruction executed NOP MOVWF PORTB write to PORTB 1998 Microchip Technology Inc. Note: MOVF PORTB,W Therefore, at higher clock frequencies, a write followed by a read may be problematic. DS30430C-page 25 PIC16F8X NOTES: DS30430C-page 26 1998 Microchip Technology Inc. PIC16F8X 6.0 TIMER0 MODULE AND TMR0 REGISTER edge select bit, T0SE (OPTION_REG<4>). Clearing bit T0SE selects the rising edge. Restrictions on the external clock input are discussed in detail in Section 6.2. The Timer0 module timer/counter has the following features: * * * * * * The prescaler is shared between the Timer0 Module and the Watchdog Timer. The prescaler assignment is controlled, in software, by control bit PSA (OPTION_REG<3>). Clearing bit PSA will assign the prescaler to the Timer0 Module. The prescaler is not readable or writable. When the prescaler (Section 6.3) is assigned to the Timer0 Module, the prescale value (1:2, 1:4, ..., 1:256) is software selectable. 8-bit timer/counter Readable and writable 8-bit software programmable prescaler Internal or external clock select Interrupt on overflow from FFh to 00h Edge select for external clock 6.1 Timer mode is selected by clearing the T0CS bit (OPTION_REG<5>). In timer mode, the Timer0 module (Figure 6-1) will increment every instruction cycle (without prescaler). If the TMR0 register is written, the increment is inhibited for the following two cycles (Figure 6-2 and Figure 6-3). The user can work around this by writing an adjusted value to the TMR0 register. The TMR0 interrupt is generated when the TMR0 register overflows from FFh to 00h. This overflow sets the T0IF bit (INTCON<2>). The interrupt can be masked by clearing enable bit T0IE (INTCON<5>). The T0IF bit must be cleared in software by the Timer0 Module interrupt service routine before re-enabling this interrupt. The TMR0 interrupt (Figure 6-4) cannot wake the processor from SLEEP since the timer is shut off during SLEEP. Counter mode is selected by setting the T0CS bit (OPTION_REG<5>). In this mode TMR0 will increment either on every rising or falling edge of pin RA4/T0CKI. The incrementing edge is determined by the T0 source FIGURE 6-1: TMR0 Interrupt TMR0 BLOCK DIAGRAM Data bus FOSC/4 0 PSout 1 Sync with Internal clocks 1 RA4/T0CKI pin Programmable Prescaler 8 0 TMR0 register PSout (2 cycle delay) T0SE 3 PS2, PS1, PS0 Set bit T0IF on Overflow PSA T0CS Note 1: Bits T0CS, T0SE, PS2, PS1, PS0 and PSA are located in the OPTION_REG register. 2: The prescaler is shared with the Watchdog Timer (Figure 6-6) FIGURE 6-2: TMR0 TIMING: INTERNAL CLOCK/NO PRESCALER 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 PC-1 PC TMR0 PC MOVWF TMR0 Instruction Fetch T0 T0+1 Instruction Executed 1998 Microchip Technology Inc. PC+1 PC+2 PC+3 MOVF TMR0,W MOVF TMR0,W MOVF TMR0,W T0+2 NT0 NT0 Write TMR0 executed Read TMR0 reads NT0 Read TMR0 reads NT0 PC+4 MOVF TMR0,W NT0 Read TMR0 reads NT0 PC+5 PC+6 MOVF TMR0,W NT0+1 Read TMR0 reads NT0 + 1 NT0+2 T0 Read TMR0 reads NT0 + 2 DS30430C-page 27 PIC16F8X FIGURE 6-3: TMR0 TIMING: INTERNAL CLOCK/PRESCALE 1:2 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 PC-1 PC Instruction Fetch PC PC+1 MOVWF TMR0 MOVF TMR0,W PC+3 T0+1 T0 TMR0 PC+2 Instruction Execute PC+5 MOVF TMR0,W PC+6 MOVF TMR0,W NT0+1 NT0 Write TMR0 executed FIGURE 6-4: PC+4 MOVF TMR0,W MOVF TMR0,W Read TMR0 reads NT0 Read TMR0 reads NT0 Read TMR0 reads NT0 Read TMR0 reads NT0 Read TMR0 reads NT0 + 1 TMR0 INTERRUPT TIMING Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 OSC1 CLKOUT(3) TMR0 timer FEh T0IF bit 4 (INTCON<2>) 1 FFh 00h 01h 02h 1 GIE bit (INTCON<7>) Interrupt Latency(2) INSTRUCTION FLOW PC PC Instruction fetched Inst (PC) Instruction executed Inst (PC-1) PC +1 PC +1 Inst (PC+1) Inst (PC) Dummy cycle 0004h 0005h Inst (0004h) Inst (0005h) Dummy cycle Inst (0004h) Note 1: T0IF interrupt flag is sampled here (every Q1). 2: Interrupt latency = 3.25Tcy, where Tcy = instruction cycle time. 3: CLKOUT is available only in RC oscillator mode. 4: The timer clock (after the synchronizer circuit) which increments the timer from FFh to 00h immediately sets the T0IF bit. The TMR0 register will roll over 3 Tosc cycles later. DS30430C-page 28 1998 Microchip Technology Inc. PIC16F8X 6.2 Using TMR0 with External Clock 6.2.2 TMR0 INCREMENT DELAY When an external clock input is used for TMR0, it must meet certain requirements. The external clock requirement is due to internal phase clock (TOSC) synchronization. Also, there is a delay in the actual incrementing of the TMR0 register after synchronization. Since the prescaler output is synchronized with the internal clocks, there is a small delay from the time the external clock edge occurs to the time the Timer0 Module is actually incremented. Figure 6-5 shows the delay from the external clock edge to the timer incrementing. 6.2.1 6.3 EXTERNAL CLOCK SYNCHRONIZATION Prescaler When no prescaler is used, the external clock input is the same as the prescaler output. The synchronization of pin RA4/T0CKI with the internal phase clocks is accomplished by sampling the prescaler output on the Q2 and Q4 cycles of the internal phase clocks (Figure 6-5). Therefore, it is necessary for T0CKI to be high for at least 2Tosc (plus a small RC delay) and low for at least 2Tosc (plus a small RC delay). Refer to the electrical specification of the desired device. An 8-bit counter is available as a prescaler for the Timer0 Module, or as a postscaler for the Watchdog Timer (Figure 6-6). For simplicity, this counter is being referred to as "prescaler" throughout this data sheet. Note that there is only one prescaler available which is mutually exclusive between the Timer0 Module and the Watchdog Timer. Thus, a prescaler assignment for the Timer0 Module means that there is no prescaler for the Watchdog Timer, and vice-versa. When a prescaler is used, the external clock input is divided by an asynchronous ripple counter type prescaler so that the prescaler output is symmetrical. For the external clock to meet the sampling requirement, the ripple counter must be taken into account. Therefore, it is necessary for T0CKI to have a period of at least 4Tosc (plus a small RC delay) divided by the prescaler value. The only requirement on T0CKI high and low time is that they do not violate the minimum pulse width requirement of 10 ns. Refer to parameters 40, 41 and 42 in the AC Electrical Specifications of the desired device. The PSA and PS2:PS0 bits (OPTION_REG<3:0>) determine the prescaler assignment and prescale ratio. 1998 Microchip Technology Inc. When assigned to the Timer0 Module, all instructions writing to the Timer0 Module (e.g., CLRF 1, MOVWF 1, BSF 1,x ....etc.) will clear the prescaler. When assigned to WDT, a CLRWDT instruction will clear the prescaler along with the Watchdog Timer. The prescaler is not readable or writable. DS30430C-page 29 PIC16F8X FIGURE 6-5: TIMER0 TIMING WITH EXTERNAL CLOCK Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Ext. Clock Input or Prescaler Out (Note 2) (Note 3) Ext. Clock/Prescaler Output After Sampling Increment TMR0 (Q4) TMR0 T0 T0 + 1 T0 + 2 Note 1: Delay from clock input change to TMR0 increment is 3Tosc to 7Tosc. (Duration of Q = Tosc). Therefore, the error in measuring the interval between two edges on TMR0 input = 4Tosc max. 2: External clock if no prescaler selected, Prescaler output otherwise. 3: The arrows indicate where sampling occurs. A small clock pulse may be missed by sampling. FIGURE 6-6: BLOCK DIAGRAM OF THE TMR0/WDT PRESCALER Data Bus CLKOUT (= Fosc/4) 0 RA4/T0CKI pin M U X 8 1 M U X 0 1 SYNC 2 Cycles TMR0 register T0SE T0CS 0 Watchdog Timer 1 M U X Set bit T0IF on overflow PSA 8-bit Prescaler 8 8 - to - 1MUX PS2:PS0 PSA WDT Enable bit 1 0 MUX PSA WDT time-out Note: T0CS, T0SE, PSA, PS2:PS0 are bits in the OPTION_REG register. DS30430C-page 30 1998 Microchip Technology Inc. PIC16F8X 6.3.1 SWITCHING PRESCALER ASSIGNMENT EXAMPLE 6-1: The prescaler assignment is fully under software control (i.e., it can be changed "on the fly" during program execution). Note: To avoid an unintended device RESET, the following instruction sequence (Example 6-1) must be executed when changing the prescaler assignment from Timer0 to the WDT. This sequence must be taken even if the WDT is disabled. To change prescaler from the WDT to the Timer0 module use the sequence shown in Example 6-2. TABLE 6-1 Address CHANGING PRESCALER (TIMER0WDT) BCF CLRF STATUS, RP0 TMR0 BSF CLRWDT MOVLW MOVWF BCF STATUS, RP0 b'xxxx1xxx' OPTION_REG STATUS, RP0 EXAMPLE 6-2: ;Bank 0 ;Clear TMR0 ; and Prescaler ;Bank 1 ;Clears WDT ;Select new ; prescale value ;Bank 0 CHANGING PRESCALER (WDTTIMER0) CLRWDT BSF MOVLW STATUS, RP0 b'xxxx0xxx' MOVWF BCF OPTION_REG STATUS, RP0 ;Clear WDT and ; prescaler ;Bank 1 ;Select TMR0, new ; prescale value ' and clock source ; ;Bank 0 REGISTERS ASSOCIATED WITH TIMER0 Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Timer0 module's register Value on Power-on Reset Value on all other resets xxxx xxxx uuuu uuuu 01h TMR0 0Bh INTCON GIE EEIE T0IE INTE RBIE T0IF INTF RBIF 0000 000x 0000 0000 81h OPTION_ REG RBPU INTEDG T0CS T0SE PSA PS2 PS1 PS0 1111 1111 1111 1111 85h TRISA -- -- -- TRISA4 TRISA3 TRISA2 TRISA1 TRISA0 ---1 1111 ---1 1111 Legend: x = unknown, u = unchanged. - = unimplemented read as '0'. Shaded cells are not associated with Timer0. 1998 Microchip Technology Inc. DS30430C-page 31 PIC16F8X NOTES: DS30430C-page 32 1998 Microchip Technology Inc. PIC16F8X 7.0 DATA EEPROM MEMORY The EEPROM data memory is readable and writable during normal operation (full VDD range). This memory is not directly mapped in the register file space. Instead it is indirectly addressed through the Special Function Registers. There are four SFRs used to read and write this memory. These registers are: * * * * EECON1 EECON2 EEDATA EEADR data memory is rated for high erase/write cycles. The write time is controlled by an on-chip timer. The writetime will vary with voltage and temperature as well as from chip to chip. Please refer to AC specifications for exact limits. When the device is code protected, the CPU may continue to read and write the data EEPROM memory. The device programmer can no longer access this memory. 7.1 EEDATA holds the 8-bit data for read/write, and EEADR holds the address of the EEPROM location being accessed. PIC16F8X devices have 64 bytes of data EEPROM with an address range from 0h to 3Fh. The EEPROM data memory allows byte read and write. A byte write automatically erases the location and writes the new data (erase before write). The EEPROM FIGURE 7-1: EEADR The EEADR register can address up to a maximum of 256 bytes of data EEPROM. Only the first 64 bytes of data EEPROM are implemented. The upper two bits are address decoded. This means that these two bits must always be '0' to ensure that the address is in the 64 byte memory space. EECON1 REGISTER (ADDRESS 88h) U U U R/W-0 R/W-x R/W-0 R/S-0 R/S-x -- -- -- EEIF WRERR WREN WR RD bit7 bit0 R W S U = Readable bit = Writable bit = Settable bit = Unimplemented bit, read as `0' - n = Value at POR reset bit 7:5 Unimplemented: Read as '0' bit 4 EEIF: EEPROM Write Operation Interrupt Flag bit 1 = The write operation completed (must be cleared in software) 0 = The write operation is not complete or has not been started bit 3 WRERR: EEPROM Error Flag bit 1 = A write operation is prematurely terminated (any MCLR reset or any WDT reset during normal operation) 0 = The write operation completed bit 2 WREN: EEPROM Write Enable bit 1 = Allows write cycles 0 = Inhibits write to the data EEPROM bit 1 WR: Write Control bit 1 = initiates a write cycle. (The bit is cleared by hardware once write is complete. The WR bit can only be set (not cleared) in software. 0 = Write cycle to the data 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). 0 = Does not initiate an EEPROM read 1998 Microchip Technology Inc. DS30430C-page 33 PIC16F8X EECON1 and EECON2 Registers EECON1 is the control register with five low order bits physically implemented. The upper-three bits are nonexistent and read as '0's. Control bits RD and WR initiate read and write, respectively. These bits cannot be cleared, only set, in software. They are cleared in hardware at completion of the read or write operation. The inability to clear the WR bit in software prevents the accidental, premature termination of a write operation. The WREN bit, when set, will allow a write operation. On power-up, the WREN bit is clear. The WRERR bit is set when a write operation is interrupted by a MCLR reset or a WDT time-out reset during normal operation. In these situations, following reset, the user can check the WRERR bit and rewrite the location. The data and address will be unchanged in the EEDATA and EEADR registers. Interrupt flag bit EEIF is set when write is complete. It must be cleared in software. EECON2 is not a physical register. Reading EECON2 will read all '0's. The EECON2 register is used exclusively in the Data EEPROM write sequence. 7.3 Reading the EEPROM Data Memory To read a data memory location, the user must write the address to the EEADR register and then set control bit RD (EECON1<0>). The data is available, in the very next cycle, in the EEDATA register; therefore it can be read in the next instruction. EEDATA will hold this value until another read or until it is written to by the user (during a write operation). EXAMPLE 7-1: BCF MOVLW MOVWF BSF BSF BCF MOVF DATA EEPROM READ STATUS, RP0 CONFIG_ADDR EEADR STATUS, RP0 EECON1, RD STATUS, RP0 EEDATA, W DS30430C-page 34 ; ; ; ; ; ; ; Bank 0 7.4 Writing to the EEPROM Data Memory To write an EEPROM data location, the user must first write the address to the EEADR register and the data to the EEDATA register. Then the user must follow a specific sequence to initiate the write for each byte. EXAMPLE 7-1: Required Sequence 7.2 DATA EEPROM WRITE BSF BCF BSF MOVLW MOVWF MOVLW MOVWF BSF STATUS, RP0 INTCON, GIE EECON1, WREN 55h EECON2 AAh EECON2 EECON1,WR BSF INTCON, GIE ; ; ; ; ; ; ; ; ; ; Bank 1 Disable INTs. Enable Write Write 55h Write AAh Set WR bit begin write Enable INTs. The write will not initiate if the above sequence is not exactly followed (write 55h to EECON2, write AAh to EECON2, then set WR bit) for each byte. We strongly recommend that interrupts be disabled during this code segment. Additionally, the WREN bit in EECON1 must be set to enable write. This mechanism prevents accidental writes to data EEPROM due to errant (unexpected) code execution (i.e., lost programs). The user should keep the WREN bit clear at all times, except when updating EEPROM. The WREN bit is not cleared by hardware After a write sequence has been initiated, clearing the WREN bit will not affect this write cycle. The WR bit will be inhibited from being set unless the WREN bit is set. At the completion of the write cycle, the WR bit is cleared in hardware and the EE Write Complete Interrupt Flag bit (EEIF) is set. The user can either enable this interrupt or poll this bit. EEIF must be cleared by software. Address to read Bank 1 EE Read Bank 0 W = EEDATA 1998 Microchip Technology Inc. PIC16F8X 7.5 Write Verify SUBWF EEDATA, W BTFSS STATUS, Z GOTO WRITE_ERR : : Depending on the application, good programming practice may dictate that the value written to the Data EEPROM should be verified (Example 7-1) to the desired value to be written. This should be used in applications where an EEPROM bit will be stressed near the specification limit. The Total Endurance disk will help determine your comfort level. 7.6 WRITE VERIFY BCF : : MOVF BSF STATUS, RP0 ; ; ; EEDATA, W ; STATUS, RP0 ; BSF EECON1, RD Bank 0 Any code can go here 7.7 Must be in Bank 0 Bank 1 Data EEPROM Operation during Code Protect When the device is code protected, the CPU is able to read and write unscrambled data to the Data EEPROM. ; YES, Read the ; value written STATUS, RP0 ; Bank 0 BCF ; ; Is the value written (in W reg) and ; read (in EEDATA) the same? ; Address Protection Against Spurious Writes The write initiate sequence and the WREN bit together help prevent an accidental write during brown-out, power glitch, or software malfunction. READ TABLE 7-1 Is difference 0? NO, Write error YES, Good write Continue program 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 built in. On power-up, WREN is cleared. Also, the Power-up Timer (72 ms duration) prevents EEPROM write. Generally the EEPROM write failure will be a bit which was written as a '1', but reads back as a '0' (due to leakage off the bit). EXAMPLE 7-1: ; ; ; ; ; For ROM devices, there are two code protection bits (Section 8.1). One for the ROM program memory and one for the Data EEPROM memory. REGISTERS/BITS ASSOCIATED WITH DATA EEPROM Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Value on Power-on Reset Value on all other resets 08h EEDATA EEPROM data register xxxx xxxx uuuu uuuu 09h EEADR EEPROM address register xxxx xxxx uuuu uuuu ---0 x000 ---0 q000 ---- ---- ---- ---- 88h EECON1 89h EECON2 -- -- -- EEPROM control register 2 EEIF WRERR WREN WR RD Legend: x = unknown, u = unchanged, - = unimplemented read as '0', q = value depends upon condition. Shaded cells are not used by Data EEPROM. 1998 Microchip Technology Inc. DS30430C-page 35 PIC16F8X NOTES: DS30430C-page 36 1998 Microchip Technology Inc. PIC16F8X 8.0 SPECIAL FEATURES OF THE CPU What sets a microcontroller apart from other processors are special circuits to deal with the needs of real time applications. The PIC16F8X has a host of such features intended to maximize system reliability, minimize cost through elimination of external components, provide power saving operating modes and offer code protection. These features are: * OSC Selection * Reset - Power-on Reset (POR) - Power-up Timer (PWRT) - Oscillator Start-up Timer (OST) * Interrupts * Watchdog Timer (WDT) * SLEEP * Code protection * ID locations * In-circuit serial programming The PIC16F8X has a Watchdog Timer which can be shut off only through configuration bits. It runs off its own RC oscillator for added reliability. There are two timers that offer necessary delays on power-up. One is the Oscillator Start-up Timer (OST), intended to keep the chip in reset until the crystal oscillator is stable. The other is the Power-up Timer (PWRT), which provides a fixed delay of 72 ms (nominal) on power-up only. This design keeps the device in reset while the power supply stabilizes. With these two timers on-chip, most applications need no external reset circuitry. SLEEP mode offers a very low current power-down mode. The user can wake-up from SLEEP through external reset, Watchdog Timer time-out or through an interrupt. Several oscillator options are provided to allow the part to fit the application. The RC oscillator option saves system cost while the LP crystal option saves power. A set of configuration bits are used to select the various options. 1998 Microchip Technology Inc. DS30430C-page 37 PIC16F8X 8.1 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 in program memory location 2007h. FIGURE 8-1: Address 2007h is beyond the user program memory space and it belongs to the special test/configuration memory space (2000h - 3FFFh). This space can only be accessed during programming. To find out how to program the PIC16C84, refer to PIC16C84 EEPROM Memory Programming Specification (DS30189). CONFIGURATION WORD - PIC16CR83 AND PIC16CR84 R-u R-u R-u R-u R-u R-u R/P-u R-u R-u R-u CP CP CP CP CP CP DP CP CP CP bit13 R-u R-u R-u R-u PWRTE WDTE FOSC1 FOSC0 bit0 R = Readable bit P = Programmable bit - n = Value at POR reset u = unchanged bit 13:8 CP: Program Memory Code Protection bit 1 = Code protection off 0 = Program memory is code protected bit 7 DP: Data Memory Code Protection bit 1 = Code protection off 0 = Data memory is code protected bit 6:4 CP: Program Memory Code Protection bit 1 = Code protection off 0 = Program memory is code protected bit 3 PWRTE: Power-up Timer Enable bit 1 = Power-up timer is disabled 0 = Power-up timer is enabled bit 2 WDTE: Watchdog Timer Enable bit 1 = WDT enabled 0 = WDT disabled bit 1:0 FOSC1:FOSC0: Oscillator Selection bits 11 = RC oscillator 10 = HS oscillator 01 = XT oscillator 00 = LP oscillator DS30430C-page 38 1998 Microchip Technology Inc. PIC16F8X FIGURE 8-2: CONFIGURATION WORD - PIC16F83 AND PIC16F84 R/P-u R/P-u R/P-u R/P-u R/P-u R/P-u R/P-u R/P-u CP CP CP CP CP CP CP CP R/P-u R/P-u CP CP R/P-u R/P-u R/P-u R/P-u PWRTE WDTE FOSC1 FOSC0 bit13 bit0 R = Readable bit P = Programmable bit - n = Value at POR reset u = unchanged bit 13:4 CP: Code Protection bit 1 = Code protection off 0 = All memory is code protected bit 3 PWRTE: Power-up Timer Enable bit 1 = Power-up timer is disabled 0 = Power-up timer is enabled bit 2 WDTE: Watchdog Timer Enable bit 1 = WDT enabled 0 = WDT disabled bit 1:0 FOSC1:FOSC0: Oscillator Selection bits 11 = RC oscillator 10 = HS oscillator 01 = XT oscillator 00 = LP oscillator 8.2 Oscillator Configurations 8.2.1 OSCILLATOR TYPES The PIC16F8X can be operated in four different oscillator modes. The user can program two configuration bits (FOSC1 and FOSC0) to select one of these four modes: * * * * LP XT HS RC 8.2.2 Low Power Crystal Crystal/Resonator High Speed Crystal/Resonator Resistor/Capacitor CRYSTAL OSCILLATOR / CERAMIC RESONATORS In XT, LP or HS modes a crystal or ceramic resonator is connected to the OSC1/CLKIN and OSC2/CLKOUT pins to establish oscillation (Figure 8-3). FIGURE 8-3: CRYSTAL/CERAMIC RESONATOR OPERATION (HS, XT OR LP OSC CONFIGURATION) C1(1) OSC1 XTAL RF(3) OSC2 RS(2) C2(1) Note1: 2: 3: To internal logic SLEEP PIC16FXX See Table 8-1 for recommended values of C1 and C2. A series resistor (RS) may be required for AT strip cut crystals. RF varies with the crystal chosen. The PIC16F8X oscillator design requires the use of a parallel cut crystal. Use of a series cut crystal may give a frequency out of the crystal manufacturers specifications. When in XT, LP or HS modes, the device can have an external clock source to drive the OSC1/CLKIN pin (Figure 8-4). 1998 Microchip Technology Inc. DS30430C-page 39 PIC16F8X FIGURE 8-4: EXTERNAL CLOCK INPUT OPERATION (HS, XT OR LP OSC CONFIGURATION) OSC1 Clock from ext. system PIC16FXX Open TABLE 8-1 OSC2 CAPACITOR SELECTION FOR CERAMIC RESONATORS Ranges Tested: Mode Freq XT 455 kHz 2.0 MHz 4.0 MHz 8.0 MHz 10.0 MHz HS Note : OSC1/C1 OSC2/C2 47 - 100 pF 47 - 100 pF 15 - 33 pF 15 - 33 pF 15 - 33 pF 15 - 33 pF 15 - 33 pF 15 - 33 pF 15 - 33 pF 15 - 33 pF Recommended values of C1 and C2 are identical to the ranges tested table. Higher capacitance increases the stability of the oscillator but also increases the start-up time. These values are for design guidance only. Since each resonator has its own characteristics, the user should consult the resonator manufacturer for the appropriate values of external components. Crystals Tested: 32.768 kHz 100 kHz 200 kHz 1.0 MHz 2.0 MHz 4.0 MHz 10.0 MHz 8.2.3 Epson C-001R32.768K-A Epson C-2 100.00 KC-P STD XTL 200.000 KHz ECS ECS-10-13-2 ECS ECS-20-S-2 ECS ECS-40-S-4 ECS ECS-100-S-4 20 PPM 20 PPM 20 PPM 50 PPM 50 PPM 50 PPM 50 PPM EXTERNAL CRYSTAL OSCILLATOR CIRCUIT Either a prepackaged oscillator can be used or a simple oscillator circuit with TTL gates can be built. Prepackaged oscillators provide a wide operating range and better stability. A well-designed crystal oscillator will provide good performance with TTL gates. Two types of crystal oscillator circuits are available; one with series resonance, and one with parallel resonance. Figure 8-5 shows a parallel resonant oscillator circuit. The circuit is designed to use the fundamental frequency of the crystal. The 74AS04 inverter performs the 180-degree phase shift that a parallel oscillator requires. The 4.7 k resistor provides negative feedback for stability. The 10 k potentiometer biases the 74AS04 in the linear region. This could be used for external oscillator designs. Resonators Tested: 455 kHz 2.0 MHz 4.0 MHz 8.0 MHz 10.0 MHz Panasonic EFO-A455K04B Murata Erie CSA2.00MG Murata Erie CSA4.00MG Murata Erie CSA8.00MT Murata Erie CSA10.00MTZ 0.3% 0.5% 0.5% 0.5% 0.5% FIGURE 8-5: EXTERNAL PARALLEL RESONANT CRYSTAL OSCILLATOR CIRCUIT +5V To Other Devices 10k None of the resonators had built-in capacitors. 4.7k TABLE 8-2 CAPACITOR SELECTION FOR CRYSTAL OSCILLATOR Mode Freq OSC1/C1 OSC2/C2 LP 32 kHz 200 kHz 100 kHz 2 MHz 4 MHz 4 MHz 10 MHz 68 - 100 pF 15 - 33 pF 100 - 150 pF 15 - 33 pF 15 - 33 pF 15 - 33 pF 15 - 33 pF 68 - 100 pF 15 - 33 pF 100 - 150 pF 15 - 33 pF 15 - 33 pF 15 - 33 pF 15 - 33 pF XT HS Note : Higher capacitance increases the stability of oscillator but also increases the start-up time. These values are for design guidance only. Rs may be required in HS mode as well as XT mode to avoid overdriving crystals with low drive level specification. Since each crystal has its own characteristics, the user should consult the crystal manufacturer for appropriate values of external components. PIC16FXX 74AS04 CLKIN 74AS04 10k XTAL 10k 20 pF 20 pF Figure 8-6 shows a series resonant oscillator circuit. This circuit is also designed to use the fundamental frequency of the crystal. The inverter performs a 180-degree phase shift. The 330 k resistors provide the negative feedback to bias the inverters in their linear region. For VDD > 4.5V, C1 = C2 30 pF is recommended. DS30430C-page 40 1998 Microchip Technology Inc. PIC16F8X FIGURE 8-6: EXTERNAL SERIES RESONANT CRYSTAL OSCILLATOR CIRCUIT FIGURE 8-7: RC OSCILLATOR MODE VDD Rext 330 k 330 k 74AS04 74AS04 To Other Devices PIC16FXX Cext 74AS04 CLKIN Fosc/4 Recommended values: XTAL Note: RC OSCILLATOR For timing insensitive applications the RC device option offers additional cost savings. The RC oscillator frequency is a function of the supply voltage, the resistor (Rext) values, capacitor (Cext) values, and the operating temperature. In addition to this, the oscillator frequency will vary from unit to unit due to normal process parameter variation. Furthermore, the difference in lead frame capacitance between package types also affects the oscillation frequency, especially for low Cext values. The user needs to take into account variation due to tolerance of the external R and C components. Figure 8-7 shows how an R/C combination is connected to the PIC16F8X. For Rext values below 4 k, the oscillator operation may become unstable, or stop completely. For very high Rext values (e.g., 1 M), the oscillator becomes sensitive to noise, humidity and leakage. Thus, we recommend keeping Rext between 5 k and 100 k. Although the oscillator will operate with no external capacitor (Cext = 0 pF), we recommend using values above 20 pF for noise and stability reasons. With little or no external capacitance, the oscillation frequency can vary dramatically due to changes in external capacitances, such as PCB trace capacitance or package lead frame capacitance. See the electrical specification section for RC frequency variation from part to part due to normal process variation. The variation is larger for larger R (since leakage current variation will affect RC frequency more for large R) and for smaller C (since variation of input capacitance has a greater affect on RC frequency). PIC16FXX VSS 0.1 F 8.2.4 Internal clock OSC1 8.3 OSC2/CLKOUT 5 k Rext 100 k Cext > 20pF When the device oscillator is in RC mode, do not drive the OSC1 pin with an external clock or you may damage the device. Reset The PIC16F8X differentiates between various kinds of reset: * * * * * Power-on Reset (POR) MCLR reset during normal operation MCLR reset during SLEEP WDT Reset (during normal operation) WDT Wake-up (during SLEEP) Figure 8-8 shows a simplified block diagram of the on-chip reset circuit. The MCLR reset path has a noise filter to ignore small pulses. The electrical specifications state the pulse width requirements for the MCLR pin. Some registers are not affected in any reset condition; their status is unknown on a POR reset and unchanged in any other reset. Most other registers are reset to a "reset state" on POR, MCLR or WDT reset during normal operation and on MCLR reset during SLEEP. They are not affected by a WDT reset during SLEEP, since this reset is viewed as the resumption of normal operation. Table 8-3 gives a description of reset conditions for the program counter (PC) and the STATUS register. Table 8-4 gives a full description of reset states for all registers. The TO and PD bits are set or cleared differently in different reset situations (Section 8.7). These bits are used in software to determine the nature of the reset. See the electrical specification section for variation of oscillator frequency due to VDD for given Rext/Cext values as well as frequency variation due to operating temperature. The oscillator frequency, divided by 4, is available on the OSC2/CLKOUT pin, and can be used for test purposes or to synchronize other logic (see Figure 3-2 for waveform). 1998 Microchip Technology Inc. DS30430C-page 41 PIC16F8X FIGURE 8-8: SIMPLIFIED BLOCK DIAGRAM OF ON-CHIP RESET CIRCUIT External Reset MCLR WDT Module SLEEP WDT Time_Out Reset VDD rise detect Power_on_Reset S 10-bit Ripple counter R VDD OST/PWRT OST Chip_Reset Q OSC1/ CLKIN PWRT On-chip RC OSC(1) 10-bit Ripple counter Enable PWRT Note 1: This is a separate oscillator from the RC oscillator of the CLKIN pin. DS30430C-page 42 See Table 8-5 Enable OST 1998 Microchip Technology Inc. PIC16F8X TABLE 8-3 RESET CONDITION FOR PROGRAM COUNTER AND THE STATUS REGISTER Program Counter Condition STATUS Register Power-on Reset 000h 0001 1xxx MCLR Reset during normal operation 000h 000u uuuu MCLR Reset during SLEEP 000h 0001 0uuu WDT Reset (during normal operation) 000h 0000 1uuu WDT Wake-up PC + 1 Interrupt wake-up from SLEEP PC + 1 uuu0 0uuu (1) uuu1 0uuu Legend: u = unchanged, x = unknown. Note 1: When the wake-up is due to an interrupt and the GIE bit is set, the PC is loaded with the interrupt vector (0004h). TABLE 8-4 Register W RESET CONDITIONS FOR ALL REGISTERS Address Power-on Reset MCLR Reset during: - normal operation - SLEEP WDT Reset during normal operation Wake-up from SLEEP: - through interrupt - through WDT Time-out -- xxxx xxxx uuuu uuuu uuuu uuuu INDF 00h ---- ---- ---- ---- ---- ---- TMR0 01h xxxx xxxx uuuu uuuu uuuu uuuu PCL 02h 0000h 0000h STATUS 03h 0001 1xxx 000q quuu(3) uuuq quuu(3) FSR 04h xxxx xxxx uuuu uuuu uuuu uuuu PORTA 05h ---x xxxx ---u uuuu ---u uuuu PORTB 06h xxxx xxxx uuuu uuuu uuuu uuuu EEDATA 08h xxxx xxxx uuuu uuuu uuuu uuuu EEADR 09h xxxx xxxx uuuu uuuu uuuu uuuu PCLATH 0Ah ---0 0000 ---0 0000 ---u uuuu INTCON 0Bh 0000 000x 0000 000u uuuu uuuu(1) INDF 80h ---- ---- ---- ---- ---- ---- OPTION_REG 81h 1111 1111 1111 1111 uuuu uuuu PCL 82h 0000h 0000h PC + 1(2) PC + 1 (3) uuuq quuu(3) STATUS 83h 0001 1xxx 000q quuu FSR 84h xxxx xxxx uuuu uuuu uuuu uuuu TRISA 85h ---1 1111 ---1 1111 ---u uuuu TRISB 86h 1111 1111 1111 1111 uuuu uuuu EECON1 88h ---0 x000 ---0 q000 ---0 uuuu EECON2 89h ---- ---- ---- ---- ---- ---- PCLATH 8Ah ---0 0000 ---0 0000 ---u uuuu INTCON 8Bh 0000 000x 0000 000u uuuu uuuu(1) Legend: u = unchanged, x = unknown, - = unimplemented bit read as '0', q = value depends on condition. Note 1: One or more bits in INTCON will be affected (to cause wake-up). 2: When the wake-up is due to an interrupt and the GIE bit is set, the PC is loaded with the interrupt vector (0004h). 3: Table 8-3 lists the reset value for each specific condition. 1998 Microchip Technology Inc. DS30430C-page 43 PIC16F8X 8.4 Power-on Reset (POR) A Power-on Reset pulse is generated on-chip when VDD rise is detected (in the range of 1.2V - 1.7V). To take advantage of the POR, just tie the MCLR pin directly (or through a resistor) to VDD. This will eliminate external RC components usually needed to create Power-on Reset. A minimum rise time for VDD must be met for this to operate properly. See Electrical Specifications for details. When the device starts normal operation (exits the reset condition), device operating parameters (voltage, frequency, temperature, ...) must be meet to ensure operation. If these conditions are not met, the device must be held in reset until the operating conditions are met. For additional information, refer to Application Note AN607, "Power-up Trouble Shooting." The POR circuit does not produce an internal reset when VDD declines. 8.5 Power-up Timer (PWRT) The Power-up Timer (PWRT) provides a fixed 72 ms nominal time-out (TPWRT) from POR (Figure 8-10, Figure 8-11, Figure 8-12 and Figure 8-13). The Power-up Timer operates on an internal RC oscillator. The chip is kept in reset as long as the PWRT is active. The PWRT delay allows the VDD to rise to an acceptable level (Possible exception shown in Figure 8-13). FIGURE 8-9: EXTERNAL POWER-ON RESET CIRCUIT (FOR SLOW VDD POWER-UP) VDD VDD D R R1 MCLR C PIC16FXX Note 1: External Power-on Reset circuit is required only if VDD power-up rate 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 voltage drop across R does not exceed 0.2V (max leakage current spec on MCLR pin is 5 A). A larger voltage drop will degrade VIH level on the MCLR pin. 3: R1 = 100 to 1 k will limit any current flowing into MCLR from external capacitor C in the event of an MCLR pin breakdown due to ESD or EOS. A configuration bit, PWRTE, can enable/disable the PWRT. See either Figure 8-1 or Figure 8-2 for the operation of the PWRTE bit for a particular device. The power-up time delay TPWRT will vary from chip to chip due to VDD, temperature, and process variation. See DC parameters for details. 8.6 Oscillator Start-up Timer (OST) The Oscillator Start-up Timer (OST) provides a 1024 oscillator cycle delay (from OSC1 input) after the PWRT delay ends (Figure 8-10, Figure 8-11, Figure 8-12 and Figure 8-13). This ensures the crystal oscillator or resonator has started and stabilized. The OST time-out (TOST) is invoked only for XT, LP and HS modes and only on Power-on Reset or wake-up from SLEEP. When VDD rises very slowly, it is possible that the TPWRT time-out and TOST time-out will expire before VDD has reached its final value. In this case (Figure 8-13), an external power-on reset circuit may be necessary (Figure 8-9). DS30430C-page 44 1998 Microchip Technology Inc. PIC16F8X FIGURE 8-10: TIME-OUT SEQUENCE ON POWER-UP (MCLR NOT TIED TO VDD): CASE 1 VDD MCLR INTERNAL POR TPWRT PWRT TIME-OUT TOST OST TIME-OUT INTERNAL RESET FIGURE 8-11: TIME-OUT SEQUENCE ON POWER-UP (MCLR NOT TIED TO VDD): CASE 2 VDD MCLR INTERNAL POR TPWRT PWRT TIME-OUT TOST OST TIME-OUT INTERNAL RESET 1998 Microchip Technology Inc. DS30430C-page 45 PIC16F8X FIGURE 8-12: TIME-OUT SEQUENCE ON POWER-UP (MCLR TIED TO VDD): FAST VDD RISE TIME VDD MCLR INTERNAL POR TPWRT PWRT TIME-OUT TOST OST TIME-OUT INTERNAL RESET FIGURE 8-13: TIME-OUT SEQUENCE ON POWER-UP (MCLR TIED TO VDD): SLOW VDD RISE TIME V1 VDD MCLR INTERNAL POR TPWRT PWRT TIME-OUT TOST OST TIME-OUT INTERNAL RESET When VDD rises very slowly, it is possible that the TPWRT time-out and TOST time-out will expire before VDD has reached its final value. In this example, the chip will reset properly if, and only if, V1 VDD min. DS30430C-page 46 1998 Microchip Technology Inc. PIC16F8X 8.7 Time-out Sequence and Power-down Status Bits (TO/PD) On power-up (Figure 8-10, Figure 8-11, Figure 8-12 and Figure 8-13) the time-out sequence is as follows: First PWRT time-out is invoked after a POR has expired. Then the OST is activated. The total time-out will vary based on oscillator configuration and PWRTE configuration bit status. For example, in RC mode with the PWRT disabled, there will be no time-out at all. TABLE 8-5 Power-up PWRT Enabled PWRT Disabled Wake-up from SLEEP XT, HS, LP 72 ms + 1024TOSC 1024TOSC 1024TOSC RC 72 ms -- -- Table 8-6 shows the significance of the TO and PD bits. Table 8-3 lists the reset conditions for some special registers, while Table 8-4 lists the reset conditions for all the registers. TO PD 1 0 x 0 0 1 1 1 x 0 1 0 1 0 A brown-out is a condition where device power (VDD) dips below its minimum value, but not to zero, and then recovers. The device should be reset in the event of a brown-out. To reset a PIC16F8X device when a brown-out occurs, external brown-out protection circuits may be built, as shown in Figure 8-14 and Figure 8-15. VDD VDD 33k 10k Since the time-outs occur from the POR reset pulse, if MCLR is kept low long enough, the time-outs will expire. Then bringing MCLR high, execution will begin immediately (Figure 8-10). This is useful for testing purposes or to synchronize more than one PIC16F8X device when operating in parallel. TABLE 8-6 Reset on Brown-Out FIGURE 8-14: BROWN-OUT PROTECTION CIRCUIT 1 TIME-OUT IN VARIOUS SITUATIONS Oscillator Configuration 8.8 STATUS BITS AND THEIR SIGNIFICANCE Condition Power-on Reset Illegal, TO is set on POR Illegal, PD is set on POR WDT Reset (during normal operation) WDT Wake-up MCLR Reset during normal operation MCLR Reset during SLEEP or interrupt wake-up from SLEEP 40k PIC16F8X This circuit will activate reset when VDD goes below (Vz + 0.7V) where Vz = Zener voltage. FIGURE 8-15: BROWN-OUT PROTECTION CIRCUIT 2 VDD VDD R1 Q1 MCLR R2 40k PIC16F8X This brown-out circuit is less expensive, although less accurate. Transistor Q1 turns off when VDD is below a certain level such that: VDD * 1998 Microchip Technology Inc. MCLR R1 R1 + R2 = 0.7V DS30430C-page 47 PIC16F8X 8.9 Interrupts The PIC16F8X has 4 sources of interrupt: * * * * External interrupt RB0/INT pin TMR0 overflow interrupt PORTB change interrupts (pins RB7:RB4) Data EEPROM write complete interrupt The interrupt control register (INTCON) records individual interrupt requests in flag bits. It also contains the individual and global interrupt enable bits. The global interrupt enable bit, GIE (INTCON<7>) enables (if set) all un-masked interrupts or disables (if cleared) all interrupts. Individual interrupts can be disabled through their corresponding enable bits in INTCON register. Bit GIE is cleared on reset. The "return from interrupt" instruction, RETFIE, exits interrupt routine as well as sets the GIE bit, which re-enable interrupts. FIGURE 8-16: INTERRUPT LOGIC T0IF T0IE INTF INTE The RB0/INT pin interrupt, the RB port change interrupt and the TMR0 overflow interrupt flags are contained in the INTCON register. When an interrupt is responded to; the GIE bit is cleared to disable any further interrupt, the return address is pushed onto the stack and the PC is loaded with 0004h. For external interrupt events, such as the RB0/INT pin or PORTB change interrupt, the interrupt latency will be three to four instruction cycles. The exact latency depends when the interrupt event occurs (Figure 8-17). The latency is the same for both one and two cycle instructions. Once in the interrupt service routine the source(s) of the interrupt can be determined by polling the interrupt flag bits. The interrupt flag bit(s) must be cleared in software before re-enabling interrupts to avoid infinite interrupt requests. Note 1: Individual interrupt flag bits are set regardless of the status of their corresponding mask bit or the GIE bit. Wake-up (If in SLEEP mode) Interrupt to CPU RBIF RBIE EEIF EEIE GIE DS30430C-page 48 1998 Microchip Technology Inc. PIC16F8X FIGURE 8-17: INT PIN INTERRUPT TIMING Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 OSC1 CLKOUT 3 4 INT pin 1 1 INTF flag (INTCON<1>) Interrupt Latency 2 5 GIE bit (INTCON<7>) INSTRUCTION FLOW PC PC Instruction fetched Inst (PC) Instruction executed Inst (PC-1) PC+1 Inst (PC+1) Inst (PC) 0004h PC+1 -- Dummy Cycle 0005h Inst (0004h) Inst (0005h) Dummy Cycle Inst (0004h) Note 1: INTF flag is sampled here (every Q1). 2: Interrupt latency = 3-4Tcy where Tcy = instruction cycle time. Latency is the same whether Inst (PC) is a single cycle or a 2-cycle instruction. 3: CLKOUT is available only in RC oscillator mode. 4: For minimum width of INT pulse, refer to AC specs. 5: INTF is enabled to be set anytime during the Q4-Q1 cycles. 8.9.1 INT INTERRUPT External interrupt on RB0/INT pin is edge triggered: either rising if INTEDG bit (OPTION_REG<6>) is set, or falling, if INTEDG bit is clear. When a valid edge appears on the RB0/INT pin, the INTF bit (INTCON<1>) is set. This interrupt can be disabled by clearing control bit INTE (INTCON<4>). Flag bit INTF must be cleared in software via the interrupt service routine before re-enabling this interrupt. The INT interrupt can wake the processor from SLEEP (Section 8.12) only if the INTE bit was set prior to going into SLEEP. The status of the GIE bit decides whether the processor branches to the interrupt vector following wake-up. 8.9.2 8.9.3 PORT RB INTERRUPT 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>) (Section 5.2). Note 1: For a change on the I/O pin to be recognized, the pulse width must be at least TCY wide. TMR0 INTERRUPT An overflow (FFh 00h) in TMR0 will set flag bit T0IF (INTCON<2>). The interrupt can be enabled/disabled by setting/clearing enable bit T0IE (INTCON<5>) (Section 6.0). 1998 Microchip Technology Inc. DS30430C-page 49 PIC16F8X 8.10 Context Saving During Interrupts During an interrupt, only the return PC value is saved on the stack. Typically, users wish to save key register values during an interrupt (e.g., W register and STATUS register). This is implemented in software. Example 8-1 stores and restores the STATUS and W register's values. The User defined registers, W_TEMP and STATUS_TEMP are the temporary storage locations for the W and STATUS registers values. Example 8-1 does the following: a) b) c) d) e) Stores the W register. Stores the STATUS register in STATUS_TEMP. Executes the Interrupt Service Routine code. Restores the STATUS (and bank select bit) register. Restores the W register. EXAMPLE 8-1: SAVING STATUS AND W REGISTERS IN RAM PUSH MOVWF SWAPF MOVWF : : : : SWAPF W_TEMP STATUS, W STATUS_TEMP MOVWF STATUS SWAPF SWAPF W_TEMP, F W_TEMP, W ISR POP DS30430C-page 50 STATUS_TEMP, W ; ; ; : ; ; ; ; ; ; ; ; ; Copy W to TEMP register, Swap status to be saved into W Save status to STATUS_TEMP register Interrupt Service Routine should configure Bank as required Swap nibbles in STATUS_TEMP register and place result into W Move W into STATUS register (sets bank to original state) Swap nibbles in W_TEMP and place result in W_TEMP Swap nibbles in W_TEMP and place result into W 1998 Microchip Technology Inc. PIC16F8X 8.11 Watchdog Timer (WDT) The Watchdog Timer is a free running on-chip RC oscillator which does not require any external components. This RC oscillator is separate from the RC oscillator of the OSC1/CLKIN pin. That means that the WDT will run even if the clock on the OSC1/CLKIN and OSC2/CLKOUT pins of the device has been stopped, for example, by execution of a SLEEP instruction. During normal operation a WDT time-out generates a device RESET. If the device is in SLEEP mode, a WDT Wake-up causes the device to wake-up and continue with normal operation. The WDT can be permanently disabled by programming configuration bit WDTE as a '0' (Section 8.1). 8.11.1 WDT PERIOD The WDT has a nominal time-out period of 18 ms, (with no prescaler). The time-out periods vary with temperature, VDD and process variations from part to part (see DC specs). If longer time-out periods are desired, a prescaler with a division ratio of up to 1:128 can be assigned to the WDT under software control by writing to the OPTION_REG register. Thus, time-out periods up to 2.3 seconds can be realized. The CLRWDT and SLEEP instructions clear the WDT and the postscaler (if assigned to the WDT) and prevent it from timing out and generating a device RESET condition. The TO bit in the STATUS register will be cleared upon a WDT time-out. 8.11.2 WDT PROGRAMMING CONSIDERATIONS It should also be taken into account that under worst case conditions (VDD = Min., Temperature = Max., max. WDT prescaler) it may take several seconds before a WDT time-out occurs. FIGURE 8-18: WATCHDOG TIMER BLOCK DIAGRAM From TMR0 Clock Source (Figure 6-6) 0 WDT Timer * 1 M U X Postscaler 8 8 - to -1 MUX PS2:PS0 * To TMR0 (Figure 6-6) PSA WDT Enable Bit 1 0 MUX PSA WDT Time-out Note: PSA and PS2:PS0 are bits in the OPTION_REG register. TABLE 8-7 SUMMARY OF REGISTERS ASSOCIATED WITH THE WATCHDOG TIMER Address Name 2007h Config. bits 81h OPTION_ REG Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Value on Power-on Reset (2) (2) (2) (2) PWRTE(1) WDTE FOSC1 FOSC0 (2) RBPU INTEDG T0CS T0SE PSA PS2 PS1 PS0 1111 1111 Value on all other resets 1111 1111 Legend: x = unknown. Shaded cells are not used by the WDT. Note 1: See Figure 8-1 and Figure 8-2 for operation of the PWRTE bit. 2: See Figure 8-1, Figure 8-2 and Section 8.13 for operation of the Code and Data protection bits. 1998 Microchip Technology Inc. DS30430C-page 51 PIC16F8X 8.12 Power-down Mode (SLEEP) 8.12.2 A device may be powered down (SLEEP) and later powered up (Wake-up from SLEEP). 8.12.1 SLEEP The Power-down mode is entered by executing the SLEEP instruction. If enabled, the Watchdog Timer is cleared (but keeps running), the PD bit (STATUS<3>) is cleared, the TO bit (STATUS<4>) is set, and the oscillator driver is turned off. The I/O ports maintain the status they had before the SLEEP instruction was executed (driving high, low, or hi-impedance). For the lowest current consumption in SLEEP mode, place all I/O pins at either at VDD or VSS, with no external circuitry drawing current from the I/O pins, and disable external clocks. I/O pins that are hi-impedance inputs should be pulled high or low externally to avoid switching currents caused by floating inputs. The T0CKI input should also be at VDD or VSS. The contribution from on-chip pull-ups on PORTB should be considered. The MCLR pin must be at a logic high level (VIHMC). It should be noted that a RESET generated by a WDT time-out does not drive the MCLR pin low. WAKE-UP FROM SLEEP The device can wake-up from SLEEP through one of the following events: 1. 2. 3. External reset input on MCLR pin. WDT Wake-up (if WDT was enabled). Interrupt from RB0/INT pin, RB port change, or data EEPROM write complete. Peripherals cannot generate interrupts during SLEEP, since no on-chip Q clocks are present. The first event (MCLR reset) will cause a device reset. The two latter events are considered a continuation of program execution. The TO and PD bits can be used to determine the cause of a device reset. The PD bit, which is set on power-up, is cleared when SLEEP is invoked. The TO bit is cleared if a WDT time-out occurred (and caused wake-up). While the SLEEP instruction is being executed, the next instruction (PC + 1) is pre-fetched. For the device to wake-up through an interrupt event, the corresponding interrupt enable bit must be set (enabled). Wake-up occurs regardless of the state of the GIE bit. If the GIE bit is clear (disabled), the device continues execution at the instruction after the SLEEP instruction. If the GIE bit is set (enabled), the device executes the instruction after the SLEEP instruction and then branches to the interrupt address (0004h). In cases where the execution of the instruction following SLEEP is not desirable, the user should have a NOP after the SLEEP instruction. FIGURE 8-19: WAKE-UP FROM SLEEP THROUGH INTERRUPT Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 OSC1 TOST(2) CLKOUT(4) INT pin INTF flag (INTCON<1>) Interrupt Latency (Note 2) GIE bit (INTCON<7>) Processor in SLEEP INSTRUCTION FLOW PC Instruction fetched Instruction executed Note 1: 2: 3: 4: PC Inst(PC) = SLEEP Inst(PC - 1) PC+1 Inst(PC + 1) SLEEP PC+2 PC+2 PC + 2 Inst(PC + 2) Inst(PC + 1) Dummy cycle 0004h 0005h Inst(0004h) Inst(0005h) Dummy cycle Inst(0004h) XT, HS or LP oscillator mode assumed. TOST = 1024TOSC (drawing not to scale) This delay will not be there for RC osc mode. GIE = '1' assumed. In this case after wake- up, the processor jumps to the interrupt routine. If GIE = '0', execution will continue in-line. CLKOUT is not available in these osc modes, but shown here for timing reference. DS30430C-page 52 1998 Microchip Technology Inc. PIC16F8X 8.12.3 WAKE-UP USING INTERRUPTS When global interrupts are disabled (GIE cleared) and any interrupt source has both its interrupt enable bit and interrupt flag bit set, one of the following will occur: * If the interrupt occurs before the execution of a SLEEP instruction, the SLEEP instruction will complete as a NOP. Therefore, the WDT and WDT postscaler will not be cleared, the TO bit will not be set and PD bits will not be cleared. * If the interrupt occurs during or after the execution of a SLEEP instruction, the device will immediately wake up from sleep. The SLEEP instruction will be completely executed before the wake-up. Therefore, the WDT and WDT postscaler will be cleared, the TO bit will be set and the PD bit will be cleared. Even if the flag bits were checked before executing a SLEEP instruction, it may be possible for flag bits to become set before the SLEEP instruction completes. To determine whether a SLEEP instruction executed, test the PD bit. If the PD bit is set, the SLEEP instruction was executed as a NOP. To ensure that the WDT is cleared, a CLRWDT instruction should be executed before a SLEEP instruction. 8.13 Program Verification/Code Protection If the code protection bit(s) have not been programmed, the on-chip program memory can be read out for verification purposes. Note: 8.14 Microchip does not recommend code protecting widowed devices. ID Locations Four memory locations (2000h - 2003h) are designated as ID locations to store checksum or other code identification numbers. These locations are not accessible during normal execution but are readable and writable only during program/verify. Only the 4 least significant bits of ID location are usable. 8.15 In-Circuit Serial Programming PIC16F8X microcontrollers 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. Customers can manufacture boards with unprogrammed devices, and then program the microcontroller just before shipping the product, allowing the most recent firmware or custom firmware to be programmed. The device is placed into a program/verify mode by holding the RB6 and RB7 pins low, while raising the MCLR pin from VIL to VIHH (see programming specification). RB6 becomes the programming clock and RB7 becomes the programming data. Both RB6 and RB7 are Schmitt Trigger inputs in this mode. After reset, to place the device into programming/verify mode, the program counter (PC) points to location 00h. A 6-bit command is then supplied to the device, 14-bits of program data is then supplied to or from the device, using load or read-type instructions. For complete details of serial programming, please refer to the PIC16CXX Programming Specifications (Literature #DS30189). FIGURE 8-20: TYPICAL IN-SYSTEM SERIAL PROGRAMMING CONNECTION External Connector Signals To Normal Connections PIC16FXX +5V VDD 0V VSS VPP MCLR/VPP CLK RB6 Data I/O RB7 For ROM devices, these values are submitted along with the ROM code. VDD To Normal Connections For ROM devices, both the program memory and Data EEPROM memory may be read, but only the Data EEPROM memory may be programmed. 1998 Microchip Technology Inc. DS30430C-page 53 PIC16F8X DS30430C-page 54 1998 Microchip Technology Inc. PIC16F8X 9.0 INSTRUCTION SET SUMMARY Each PIC16CXX instruction is a 14-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 PIC16CXX instruction set summary in Table 9-2 lists byte-oriented, bit-oriented, and literal and control operations. Table 9-1 shows the opcode field descriptions. For byte-oriented instructions, 'f' represents a file register designator and 'd' represents a destination designator. The file register designator specifies which file register is to be used by the instruction. The destination designator specifies where the result of the operation is to be placed. If 'd' is zero, the result is placed in the W register. If 'd' is one, the result is placed in the file register specified in the instruction. For bit-oriented instructions, 'b' represents a bit field designator which selects the number of the bit affected by the operation, while 'f' represents the number of the file in which the bit is located. For literal and control operations, 'k' represents an eight or eleven bit constant or literal value. TABLE 9-1 OPCODE FIELD DESCRIPTIONS Field Description f Register file address (0x00 to 0x7F) W Working register (accumulator) b Bit address within an 8-bit file register k Literal field, constant data or label x Don't care location (= 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. d Label name TOS Top of Stack PC Program Counter PCLATH Program Counter High Latch GIE Global Interrupt Enable bit WDT Watchdog Timer/Counter TO Time-out bit PD Power-down bit dest Destination either the W register or the specified register file location [ ] Options italics * Byte-oriented operations * Bit-oriented operations * Literal and control operations All instructions are executed within one single instruction cycle, unless a conditional test is true or the program counter is changed as a result of an instruction. In this case, the execution takes two instruction cycles with the second cycle executed as a NOP. 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. Table 9-2 lists the instructions recognized by the MPASM assembler. Figure 9-1 shows the general formats that the instructions can have. Note: To maintain upward compatibility with future PIC16CXX products, do not use the OPTION and TRIS instructions. All examples use the following format to represent a hexadecimal number: 0xhh where h signifies a hexadecimal digit. FIGURE 9-1: GENERAL FORMAT FOR INSTRUCTIONS Byte-oriented file register operations 13 8 7 6 OPCODE d f (FILE #) 0 d = 0 for destination W d = 1 for destination f f = 7-bit file register address Destination select; d = 0: store result in W, d = 1: store result in file register f. Default is d = 1 label ( ) <> The instruction set is highly orthogonal and is grouped into three basic categories: Bit-oriented file register operations 13 10 9 7 6 OPCODE b (BIT #) f (FILE #) 0 b = 3-bit bit address f = 7-bit file register address Literal and control operations General 13 8 7 OPCODE Contents 0 k (literal) k = 8-bit immediate value Assigned to Register bit field In the set of User defined term (font is courier) CALL and GOTO instructions only 13 11 OPCODE 10 0 k (literal) k = 11-bit immediate value 1998 Microchip Technology Inc. DS30430C-page 55 PIC16F8X TABLE 9-2 PIC16FXX INSTRUCTION SET Mnemonic, Operands Description Cycles 14-Bit Opcode MSb LSb Status Affected Notes BYTE-ORIENTED FILE REGISTER OPERATIONS ADDWF ANDWF CLRF CLRW COMF DECF DECFSZ INCF INCFSZ IORWF MOVF MOVWF NOP RLF RRF SUBWF SWAPF XORWF f, d f, d f f, d f, d f, d f, d f, d f, d f, d f f, d f, d f, d f, d f, d Add W and f AND W with f Clear f Clear W Complement f Decrement f Decrement f, Skip if 0 Increment f Increment f, Skip if 0 Inclusive OR W with f Move f Move W to f No Operation Rotate Left f through Carry Rotate Right f through Carry Subtract W from f Swap nibbles in f Exclusive OR W with f 1 1 1 1 1 1 1(2) 1 1(2) 1 1 1 1 1 1 1 1 1 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 dfff dfff lfff 0xxx dfff dfff dfff dfff dfff dfff dfff lfff 0xx0 dfff dfff dfff dfff dfff ffff ffff ffff xxxx ffff ffff ffff ffff ffff ffff ffff ffff 0000 ffff ffff ffff ffff ffff 00bb 01bb 10bb 11bb bfff bfff bfff bfff ffff ffff ffff ffff 111x 1001 0kkk 0000 1kkk 1000 00xx 0000 01xx 0000 0000 110x 1010 kkkk kkkk kkkk 0110 kkkk kkkk kkkk 0000 kkkk 0000 0110 kkkk kkkk kkkk kkkk kkkk 0100 kkkk kkkk kkkk 1001 kkkk 1000 0011 kkkk kkkk 0111 0101 0001 0001 1001 0011 1011 1010 1111 0100 1000 0000 0000 1101 1100 0010 1110 0110 C,DC,Z Z Z Z Z Z Z Z Z C C C,DC,Z Z 1,2 1,2 2 1,2 1,2 1,2,3 1,2 1,2,3 1,2 1,2 1,2 1,2 1,2 1,2 1,2 BIT-ORIENTED FILE REGISTER OPERATIONS BCF BSF BTFSC BTFSS f, b f, b f, b f, b Bit Clear f Bit Set f Bit Test f, Skip if Clear Bit Test f, Skip if Set 1 1 1 (2) 1 (2) 01 01 01 01 1,2 1,2 3 3 LITERAL AND CONTROL OPERATIONS ADDLW ANDLW CALL CLRWDT GOTO IORLW MOVLW RETFIE RETLW RETURN SLEEP SUBLW XORLW k k k k k k k k k Add literal and W AND literal with W Call subroutine Clear Watchdog Timer Go to address Inclusive OR literal with W Move literal to W Return from interrupt Return with literal in W Return from Subroutine Go into standby mode Subtract W from literal Exclusive OR literal with W 1 1 2 1 2 1 1 2 2 2 1 1 1 11 11 10 00 10 11 11 00 11 00 00 11 11 C,DC,Z Z TO,PD Z TO,PD C,DC,Z Z Note 1: When an I/O register is modified as a function of itself ( e.g., MOVF PORTB, 1), 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 to the Timer0 Module. 3: If Program Counter (PC) is modified or a conditional test is true, the instruction requires two cycles. The second cycle is executed as a NOP. DS30430C-page 56 1998 Microchip Technology Inc. PIC16F8X 9.1 Instruction Descriptions ADDLW Add Literal and W ANDLW AND Literal with W Syntax: [label] ADDLW Syntax: [label] ANDLW Operands: 0 k 255 Operands: 0 k 255 Operation: (W) + k (W) Operation: (W) .AND. (k) (W) Status Affected: C, DC, Z Status Affected: Z Encoding: 11 k 111x kkkk kkkk Encoding: 11 k 1001 kkkk kkkk Description: The contents of the W register are added to the eight bit literal 'k' and the result is placed in the W register. Description: The contents of W register are AND'ed with the eight bit literal 'k'. The result is placed in the W register. Words: 1 Words: 1 Cycles: 1 Cycles: 1 Q Cycle Activity: Example: Q1 Q2 Q3 Q4 Decode Read literal 'k' Process data Write to W ADDLW 0x15 Q Cycle Activity: Example = = ADDWF Add W and f Q3 Q4 Process data Write to W ANDLW 0x5F W 0x10 = 0xA3 After Instruction After Instruction W Q2 Read literal "k" Before Instruction Before Instruction W Q1 Decode W 0x25 = ANDWF AND W with f 0x03 Syntax: [label] ADDWF Syntax: [label] ANDWF Operands: 0 f 127 d [0,1] Operands: 0 f 127 d [0,1] Operation: (W) + (f) (destination) Operation: (W) .AND. (f) (destination) Status Affected: C, DC, Z Status Affected: Z Encoding: 00 f,d 0111 dfff ffff Encoding: 00 f,d 0101 dfff ffff Description: Add the contents of the W register with register 'f'. If 'd' is 0 the result is stored in the W register. If 'd' is 1 the result is stored back in register 'f'. Description: AND the W register with register 'f'. If 'd' is 0 the result is stored in the W register. If 'd' is 1 the result is stored back in register 'f'. Words: 1 Words: 1 Cycles: 1 Cycles: 1 Q Cycle Activity: Example Q1 Q2 Q3 Q4 Decode Read register 'f' Process data Write to destination ADDWF FSR, 0 Before Instruction W = FSR = 1998 Microchip Technology Inc. Example Q1 Q2 Q3 Q4 Decode Read register 'f' Process data Write to destination ANDWF FSR, 1 Before Instruction 0x17 0xC2 After Instruction W = FSR = Q Cycle Activity: W = FSR = 0x17 0xC2 After Instruction 0xD9 0xC2 W = FSR = 0x17 0x02 DS30430C-page 57 PIC16F8X BCF Bit Clear f BTFSC Bit Test, Skip if Clear Syntax: [label] BCF Syntax: [label] BTFSC f,b Operands: 0 f 127 0b7 Operands: 0 f 127 0b7 Operation: 0 (f<b>) Operation: skip if (f<b>) = 0 Status Affected: None Status Affected: None Encoding: 01 f,b 00bb bfff ffff Description: Bit 'b' in register 'f' is cleared. Words: 1 Cycles: 1 Q Cycle Activity: Example Q1 Q2 Q3 Q4 Decode Read register 'f' Process data Write register 'f' BCF Encoding: 10bb bfff ffff If bit 'b' in register 'f' is '1' then the next instruction is executed. If bit 'b', in register 'f', is '0' then the next instruction is discarded, and a NOP is executed instead, making this a 2TCY instruction. Words: 1 Cycles: 1(2) Q Cycle Activity: FLAG_REG, 7 01 Description: Before Instruction Q1 Q2 Q3 Q4 Decode Read register 'f' Process data No-Operat ion Q3 Q4 FLAG_REG = 0xC7 If Skip: After Instruction FLAG_REG = 0x47 (2nd Cycle) Q1 Q2 No-Operat ion Example HERE FALSE TRUE No-Operati No-Opera No-Operat on tion ion BTFSC GOTO * * * FLAG,1 PROCESS_CODE Before Instruction PC = address HERE After Instruction BSF Bit Set f Syntax: [label] BSF Operands: 0 f 127 0b7 Operation: 1 (f<b>) Status Affected: None Encoding: Description: 01 1 Cycles: 1 Example 01bb bfff ffff Bit 'b' in register 'f' is set. Words: Q Cycle Activity: if FLAG<1> = 0, PC = address TRUE if FLAG<1>=1, PC = address FALSE f,b Q1 Q2 Q3 Q4 Decode Read register 'f' Process data Write register 'f' BSF FLAG_REG, 7 Before Instruction FLAG_REG = 0x0A After Instruction FLAG_REG = 0x8A DS30430C-page 58 1998 Microchip Technology Inc. PIC16F8X BTFSS Bit Test f, Skip if Set CALL Call Subroutine Syntax: [label] BTFSS f,b Syntax: [ label ] CALL k Operands: 0 f 127 0b<7 Operands: 0 k 2047 Operation: (PC)+ 1 TOS, k PC<10:0>, (PCLATH<4:3>) PC<12:11> Status Affected: None Operation: skip if (f<b>) = 1 Status Affected: None Encoding: Description: 01 1 Cycles: 1(2) If Skip: ffff Q1 Q2 Q3 Q4 Decode Read register 'f' Process data No-Operat ion (2nd Cycle) Q1 Q2 No-Operat ion Example bfff If bit 'b' in register 'f' is '0' then the next instruction is executed. If bit 'b' is '1', then the next instruction is discarded and a NOP is executed instead, making this a 2TCY instruction. Words: Q Cycle Activity: 11bb HERE FALSE TRUE Q3 10 Words: 1 Cycles: 2 Q Cycle Activity: FLAG,1 PROCESS_CODE 2nd Cycle Example 0kkk kkkk kkkk Call Subroutine. First, return address (PC+1) is pushed onto the stack. The eleven bit immediate address is loaded into PC bits <10:0>. The upper bits of the PC are loaded from PCLATH. CALL is a two cycle instruction. Q1 Q2 Q3 Q4 Decode Read literal 'k', Push PC to Stack Process data Write to PC Q4 No-Opera tion HERE No-Opera No-Opera No-Operat tion tion ion CALL THERE Before Instruction PC = Address HERE After Instruction Before Instruction PC = Description: 1st Cycle No-Operati No-Opera No-Operat on tion ion BTFSC GOTO * * * Encoding: address HERE PC = Address THERE TOS = Address HERE+1 After Instruction if FLAG<1> = 0, PC = address FALSE if FLAG<1> = 1, PC = address TRUE 1998 Microchip Technology Inc. DS30430C-page 59 PIC16F8X CLRF Clear f Syntax: [label] CLRF Operands: 0 f 127 Operation: 00h (f) 1Z Status Affected: Z Encoding: 00 f 0001 1fff ffff CLRW Clear W Syntax: [ label ] CLRW Operands: None Operation: 00h (W) 1Z Status Affected: Z Encoding: 00 0001 0xxx xxxx Description: The contents of register 'f' are cleared and the Z bit is set. Description: W register is cleared. Zero bit (Z) is set. Words: 1 Words: 1 Cycles: 1 Cycles: 1 Q Cycle Activity: Example Q1 Q2 Q3 Q4 Decode Read register 'f' Process data Write register 'f' CLRF Q Cycle Activity: Example FLAG_REG = 0x5A Q3 Q4 Process data Write to W CLRW = = 0x00 1 W = 0x5A After Instruction After Instruction FLAG_REG Z Q2 No-Opera tion Before Instruction Before Instruction FLAG_REG Q1 Decode W Z = = 0x00 1 CLRWDT Clear Watchdog Timer Syntax: [ label ] CLRWDT Operands: None Operation: 00h WDT 0 WDT prescaler, 1 TO 1 PD Status Affected: TO, PD Encoding: 00 0000 0110 0100 Description: CLRWDT instruction resets the Watchdog Timer. It also resets the prescaler of the WDT. Status bits TO and PD are set. Words: 1 Cycles: 1 Q Cycle Activity: Example Q1 Q2 Q3 Q4 Decode No-Opera tion Process data Clear WDT Counter CLRWDT Before Instruction WDT counter = ? After Instruction WDT counter = WDT prescaler= TO = PD = DS30430C-page 60 0x00 0 1 1 1998 Microchip Technology Inc. PIC16F8X COMF Complement f Syntax: [ label ] COMF Operands: 0 f 127 d [0,1] Operation: (f) (destination) Status Affected: Z Encoding: Description: 00 f,d 1001 dfff ffff 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'. Words: 1 Cycles: 1 Q Cycle Activity: Q1 Q2 Q3 Q4 Decode Read register 'f' Process data Write to destination DECFSZ Decrement f, Skip if 0 Syntax: [ label ] DECFSZ f,d Operands: 0 f 127 d [0,1] Operation: (f) - 1 (destination); skip if result = 0 Status Affected: None Encoding: COMF 0x13 1 Cycles: 1(2) = = 0x13 0xEC If Skip: After Instruction REG1 W Q1 Q2 Q3 Q4 Decode Read register 'f' Process data Write to destination Q3 Q4 Decrement f Syntax: [label] DECF f,d Operands: 0 f 127 d [0,1] Operation: (f) - 1 (destination) Status Affected: Z Example DECFSZ GOTO CONTINUE * * * CNT, 1 LOOP Before Instruction 00 0011 dfff ffff Description: Decrement register 'f'. If 'd' is 0 the result is stored in the W register. If 'd' is 1 the result is stored back in register 'f'. Words: 1 Cycles: 1 Example No-Opera No-Operat No-Operati tion ion on HERE PC Encoding: Q Cycle Activity: (2nd Cycle) Q1 Q2 No-Operat ion DECF ffff Words: Before Instruction = dfff The contents of register 'f' are decremented. If 'd' is 0 the result is placed in the W register. If 'd' is 1 the result is placed back in register 'f'. If the result is 1, the next instruction, is executed. If the result is 0, then a NOP is executed instead making it a 2TCY instruction. REG1,0 REG1 1011 Description: Q Cycle Activity: Example 00 Q1 Q2 Q3 Q4 Decode Read register 'f' Process data Write to destination DECF = address HERE After Instruction CNT if CNT PC if CNT PC = = = = CNT - 1 0, address CONTINUE 0, address HERE+1 CNT, 1 Before Instruction CNT Z = = 0x01 0 = = 0x00 1 After Instruction CNT Z 1998 Microchip Technology Inc. DS30430C-page 61 PIC16F8X Unconditional Branch INCF Increment f Syntax: [ label ] Syntax: [ label ] Operands: 0 k 2047 Operands: Operation: k PC<10:0> PCLATH<4:3> PC<12:11> 0 f 127 d [0,1] Operation: (f) + 1 (destination) None Status Affected: Z GOTO Status Affected: Encoding: 10 GOTO k 1kkk kkkk kkkk Encoding: 00 INCF f,d 1010 dfff ffff Description: GOTO is an unconditional branch. The eleven bit immediate value is loaded into PC bits <10:0>. The upper bits of PC are loaded from PCLATH<4:3>. GOTO is a two cycle instruction. Description: The contents of register 'f' are incremented. If 'd' is 0 the result is placed in the W register. If 'd' is 1 the result is placed back in register 'f'. Words: 1 Words: 1 Cycles: 2 Cycles: 1 Q Cycle Activity: 1st Cycle 2nd Cycle Q1 Q2 Q3 Q4 Decode Read literal 'k' Process data Write to PC No-Operat ion Q Cycle Activity: Q1 Q2 Q3 Q4 Decode Read register 'f' Process data Write to destination No-Operat No-Opera No-Operat ion tion ion Example INCF CNT, 1 Before Instruction Example GOTO THERE CNT Z After Instruction PC = DS30430C-page 62 Address THERE = = 0xFF 0 = = 0x00 1 After Instruction CNT Z 1998 Microchip Technology Inc. PIC16F8X INCFSZ Increment f, Skip if 0 IORLW Inclusive OR Literal with W Syntax: [ label ] Syntax: [ label ] Operands: 0 f 127 d [0,1] Operands: 0 k 255 Operation: (f) + 1 (destination), skip if result = 0 (W) .OR. k (W) Operation: Status Affected: Z Status Affected: 00 1 Cycles: 1(2) If Skip: dfff ffff Q1 Q2 Q3 Q4 Decode Read register 'f' Process data Write to destination Q3 Q4 (2nd Cycle) Q1 Q2 No-Operat ion Example 1111 The contents of register 'f' are incremented. If 'd' is 0 the result is placed in the W register. If 'd' is 1 the result is placed back in register 'f'. If the result is 1, the next instruction is executed. If the result is 0, a NOP is executed instead making it a 2TCY instruction. Words: Q Cycle Activity: Encoding: None Encoding: Description: INCFSZ f,d 11 IORLW k 1000 kkkk kkkk Description: The contents of the W register is OR'ed with the eight bit literal 'k'. The result is placed in the W register. Words: 1 Cycles: 1 Q Cycle Activity: Example Q1 Q2 Q3 Q4 Decode Read literal 'k' Process data Write to W IORLW 0x35 Before Instruction W = 0x9A After Instruction W Z = = 0xBF 1 No-Opera No-Opera No-Operati tion tion on HERE INCFSZ GOTO CONTINUE * * * CNT, 1 LOOP Before Instruction PC = address HERE After Instruction CNT = if CNT= PC = if CNT PC = 1998 Microchip Technology Inc. CNT + 1 0, address CONTINUE 0, address HERE +1 DS30430C-page 63 PIC16F8X IORWF Inclusive OR W with f MOVLW Move Literal to W Syntax: [ label ] Syntax: [ label ] Operands: 0 f 127 d [0,1] Operands: 0 k 255 Operation: k (W) Status Affected: None IORWF f,d Operation: (W) .OR. (f) (destination) Status Affected: Z Encoding: Description: 00 0100 dfff ffff Inclusive OR the W register with register 'f'. If 'd' is 0 the result is placed in the W register. If 'd' is 1 the result is placed back in register 'f'. Words: 1 Cycles: 1 Q Cycle Activity: Example Encoding: 11 Q2 Q3 Q4 Decode Read register 'f' Process data Write to destination IORWF 00xx kkkk kkkk Description: The eight bit literal 'k' is loaded into W register. The don't cares will assemble as 0's. Words: 1 Cycles: 1 Q Cycle Activity: Q1 MOVLW k Example Q1 Q2 Q3 Q4 Decode Read literal 'k' Process data Write to W MOVLW 0x5A After Instruction RESULT, 0 W = 0x5A Before Instruction RESULT = W = 0x13 0x91 After Instruction RESULT = W = Z = 0x13 0x93 1 MOVWF Move W to f Syntax: [ label ] 0 f 127 d [0,1] Operands: 0 f 127 Operation: (W) (f) Operation: (f) (destination) Status Affected: None Status Affected: Z Encoding: MOVF Move f Syntax: [ label ] Operands: Encoding: Description: 00 1000 dfff ffff The contents of register f is moved to a destination dependant upon the status of d. If d = 0, destination is W register. If d = 1, the destination is file register f itself. d = 1 is useful to test a file register since status flag Z is affected. Words: 1 Cycles: 1 Q Cycle Activity: MOVF f,d Q1 Q2 Q3 Q4 Decode Read register 'f' Process data Write to destination 00 MOVWF 0000 f 1fff ffff Description: Move data from W register to register 'f'. Words: 1 Cycles: 1 Q Cycle Activity: Example Q1 Q2 Q3 Q4 Decode Read register 'f' Process data Write register 'f' MOVWF OPTION_REG Before Instruction OPTION = W = 0xFF 0x4F After Instruction Example MOVF FSR, 0 After Instruction OPTION = W = 0x4F 0x4F W = value in FSR register Z =1 DS30430C-page 64 1998 Microchip Technology Inc. PIC16F8X NOP No Operation RETFIE Return from Interrupt Syntax: [ label ] Syntax: [ label ] Operands: None Operands: None Operation: No operation Operation: Status Affected: None TOS PC, 1 GIE Status Affected: None Encoding: 00 NOP 0000 Description: No operation. Words: 1 Cycles: 1 Q Cycle Activity: Q1 Decode Example 0xx0 0000 Encoding: Q2 Q3 0000 0000 1001 Description: Return from Interrupt. Stack is POPed and Top of Stack (TOS) is loaded in the PC. Interrupts are enabled by setting Global Interrupt Enable bit, GIE (INTCON<7>). This is a two cycle instruction. Words: 1 Cycles: 2 Q4 No-Opera No-Opera No-Operat tion tion ion NOP 00 RETFIE Q Cycle Activity: 1st Cycle 2nd Cycle Example Q1 Q2 Q3 Q4 Decode No-Opera tion Set the GIE bit Pop from the Stack No-Operat ion No-Opera No-Opera No-Operat tion tion ion RETFIE After Interrupt PC = GIE = OPTION Load Option Register Syntax: [ label ] Operands: None Operation: (W) OPTION TOS 1 OPTION Status Affected: None Encoding: 00 0000 0110 0010 Description: The contents of the W register are loaded in the OPTION register. This instruction is supported for code compatibility with PIC16C5X products. Since OPTION is a readable/writable register, the user can directly address it. Words: 1 Cycles: 1 Example To maintain upward compatibility with future PIC16CXX products, do not use this instruction. 1998 Microchip Technology Inc. DS30430C-page 65 PIC16F8X RETLW Return with Literal in W RETURN Return from Subroutine Syntax: [ label ] Syntax: [ label ] Operands: 0 k 255 Operands: None Operation: k (W); TOS PC Operation: TOS PC Status Affected: None Status Affected: None Encoding: Encoding: RETLW k 11 Description: 01xx kkkk kkkk The W register is loaded with the eight bit literal 'k'. The program counter is loaded from the top of the stack (the return address). This is a two cycle instruction. Words: 1 Cycles: 2 Q Cycle Activity: 1st Cycle 2nd Cycle Q1 Q2 Q3 Q4 Read literal 'k' No-Opera tion Write to W, Pop from the Stack No-Opera No-Opera No-Operat tion tion ion No-Operat ion 0000 Words: 1 Cycles: 2 1st Cycle 2nd Cycle Example Q1 Decode No-Operat ion Q2 Q3 Q4 No-Opera No-Opera Pop from tion tion the Stack No-Opera No-Opera No-Opera tion tion tion RETURN After Interrupt CALL TABLE TOS ;W contains table ;offset value ;W now has table value * * * TABLE ADDWF PC RETLW k1 RETLW k2 1000 Return from subroutine. The stack is POPed and the top of the stack (TOS) is loaded into the program counter. This is a two cycle instruction. PC = Example 0000 Description: Q Cycle Activity: Decode 00 RETURN ;W = offset ;Begin table ; * * * RETLW kn ; End of table Before Instruction W = 0x07 After Instruction W DS30430C-page 66 = value of k8 1998 Microchip Technology Inc. PIC16F8X RLF Rotate Left f through Carry RRF Rotate Right f through Carry Syntax: [ label ] Syntax: [ label ] Operands: 0 f 127 d [0,1] Operands: 0 f 127 d [0,1] Operation: See description below Operation: See description below Status Affected: C Status Affected: C Encoding: Description: RLF 00 1101 f,d dfff ffff 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 the W register. If 'd' is 1 the result is stored back in register 'f'. C Encoding: Description: 00 Register f C 1 Words: 1 Cycles: 1 Cycles: 1 Example Q1 Q2 Q3 Q4 Decode Read register 'f' Process data Write to destination RLF REG1,0 1998 Microchip Technology Inc. dfff ffff Register f Q1 Q2 Q3 Q4 Decode Read register 'f' Process data Write to destination RRF REG1,0 Before Instruction = = 1110 0110 0 = = = 1110 0110 1100 1100 1 After Instruction REG1 W C Q Cycle Activity: Example Before Instruction REG1 C 1100 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 the W register. If 'd' is 1 the result is placed back in register 'f'. Words: Q Cycle Activity: RRF f,d REG1 C = = 1110 0110 0 = = = 1110 0110 0111 0011 0 After Instruction REG1 W C DS30430C-page 67 PIC16F8X SLEEP SUBLW Subtract W from Literal Syntax: [ label ] SUBLW k Syntax: [ label ] Operands: None Operands: 0 k 255 Operation: 00h WDT, 0 WDT prescaler, 1 TO, 0 PD Operation: k - (W) (W) Status Affected: C, DC, Z SLEEP Encoding: 11 110x kkkk kkkk Description: The W register is subtracted (2's complement method) from the eight bit literal 'k'. The result is placed in the W register. The power-down status bit, PD is cleared. Time-out status bit, TO is set. Watchdog Timer and its prescaler are cleared. The processor is put into SLEEP mode with the oscillator stopped. See Section 14.8 for more details. Words: 1 Cycles: 1 Words: 1 Example 1: Cycles: 1 Status Affected: TO, PD Encoding: Description: Q Cycle Activity: 00 0000 0110 0011 Q Cycle Activity: Q1 Q2 Q3 Q4 Decode Read literal 'k' Process data Write to W SUBLW 0x02 Before Instruction Q1 Decode Q2 Q3 No-Opera No-Opera tion tion Q4 W C Z Go to Sleep = = = 1 ? ? After Instruction Example: SLEEP W C Z Example 2: = = = 1 1; result is positive 0 Before Instruction W C Z = = = 2 ? ? After Instruction W C Z Example 3: = = = 0 1; result is zero 1 Before Instruction W C Z = = = 3 ? ? After Instruction W C Z DS30430C-page 68 = = = 0xFF 0; result is negative 0 1998 Microchip Technology Inc. PIC16F8X SUBWF Subtract W from f SWAPF Swap Nibbles in f Syntax: [ label ] Syntax: [ label ] SWAPF f,d Operands: 0 f 127 d [0,1] Operands: 0 f 127 d [0,1] Operation: (f) - (W) (destination) Operation: (f<3:0>) (destination<7:4>), (f<7:4>) (destination<3:0>) Status Affected: None SUBWF f,d Status Affected: C, DC, Z Encoding: Description: 00 1 Cycles: 1 Example 1: dfff ffff Subtract (2's complement method) W register from register 'f'. If 'd' is 0 the result is stored in the W register. If 'd' is 1 the result is stored back in register 'f'. Words: Q Cycle Activity: 0010 Q1 Q2 Q3 Q4 Decode Read register 'f' Process data Write to destination SUBWF 00 Example 2: = = = = Words: 1 Cycles: 1 Q Cycle Activity: Q1 Q2 Q3 Q4 Decode Read register 'f' Process data Write to destination SWAPF REG, = = = = = = = = Example 3: = = = = REG1 = = = = REG1 W 1998 Microchip Technology Inc. = = = = 0xA5 = = 0xA5 0x5A 1 2 1; result is positive 0 2 2 ? ? TRIS Load TRIS Register Syntax: [label] Operands: 5f7 Operation: (W) TRIS register f; TRIS f Status Affected: None 0 2 1; result is zero 1 1 2 ? ? After Instruction REG1 W C Z = After Instruction Encoding: 0xFF 2 0; result is negative 0 00 0000 0110 0fff Description: The instruction is supported for code compatibility with the PIC16C5X products. Since TRIS registers are readable and writable, the user can directly address them. Words: 1 Cycles: 1 Before Instruction REG1 W C Z 0 Before Instruction 3 2 ? ? After Instruction REG1 W C Z ffff The upper and lower nibbles of register 'f' are exchanged. If 'd' is 0 the result is placed in W register. If 'd' is 1 the result is placed in register 'f'. Example Before Instruction REG1 W C Z dfff Description: After Instruction REG1 W C Z 1110 REG1,1 Before Instruction REG1 W C Z Encoding: Example To maintain upward compatibility with future PIC16CXX products, do not use this instruction. DS30430C-page 69 PIC16F8X XORLW Exclusive OR Literal with W XORWF Exclusive OR W with f Syntax: [label] Syntax: [label] Operands: 0 k 255 Operands: Operation: (W) .XOR. k (W) 0 f 127 d [0,1] Status Affected: Z Operation: (W) .XOR. (f) (destination) Status Affected: Z Encoding: 11 XORLW k 1010 kkkk kkkk Description: The contents of the W register are XOR'ed with the eight bit literal 'k'. The result is placed in the W register. Words: 1 Cycles: 1 Q Cycle Activity: Example: Q1 Q2 Q3 Q4 Decode Read literal 'k' Process data Write to W XORLW Encoding: 00 XORWF 0110 f,d dfff ffff Description: Exclusive OR the contents of the W register with register 'f'. If 'd' is 0 the result is stored in the W register. 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 register 'f' Process data Write to destination 0xAF Before Instruction W = Example 0xB5 After Instruction W = 0x1A XORWF REG 1 Before Instruction REG W = = 0xAF 0xB5 = = 0x1A 0xB5 After Instruction REG W DS30430C-page 70 1998 Microchip Technology Inc. PIC16F8X 10.0 DEVELOPMENT SUPPORT 10.1 Development Tools The PICmicr microcontrollers are supported with a full range of hardware and software development tools: * PICMASTER/PICMASTER CE Real-Time In-Circuit Emulator * ICEPIC Low-Cost PIC16C5X and PIC16CXXX In-Circuit Emulator * PRO MATE II Universal Programmer * PICSTART Plus Entry-Level Prototype Programmer * PICDEM-1 Low-Cost Demonstration Board * PICDEM-2 Low-Cost Demonstration Board * PICDEM-3 Low-Cost Demonstration Board * MPASM Assembler * MPLAB SIM Software Simulator * MPLAB-C17 (C Compiler) * Fuzzy Logic Development System (fuzzyTECH-MP) 10.2 PICMASTER: High Performance Universal In-Circuit Emulator with MPLAB IDE 10.3 ICEPIC: Low-Cost PICmicroTM In-Circuit Emulator ICEPIC is a low-cost in-circuit emulator solution for the Microchip PIC12CXXX, PIC16C5X and PIC16CXXX families of 8-bit OTP microcontrollers. ICEPIC is designed to operate on PC-compatible machines ranging from 286-AT through Pentium based machines under Windows 3.x environment. ICEPIC features real time, non-intrusive emulation. 10.4 PRO MATE II: Universal Programmer The PRO MATE II Universal Programmer is a full-featured programmer capable of operating in stand-alone mode as well as PC-hosted mode. PRO MATE II is CE compliant. The PRO MATE II has programmable VDD and VPP supplies which allows it to verify programmed memory at VDD min and VDD max for maximum reliability. It has an LCD display for displaying error messages, keys to enter commands and a modular detachable socket assembly to support various package types. In standalone mode the PRO MATE II can read, verify or program PIC12CXXX, PIC14C000, PIC16C5X, PIC16CXXX and PIC17CXX devices. It can also set configuration and code-protect bits in this mode. The PICMASTER Universal In-Circuit Emulator is intended to provide the product development engineer with a complete microcontroller design tool set for all microcontrollers in the PIC14C000, PIC12CXXX, PIC16C5X, PIC16CXXX and PIC17CXX families. PICMASTER is supplied with the MPLAB Integrated Development Environment (IDE), which allows editing, "make" and download, and source debugging from a single environment. 10.5 Interchangeable target probes allow the system to be easily reconfigured for emulation of different processors. The universal architecture of the PICMASTER allows expansion to support all new Microchip microcontrollers. PICSTART Plus supports all PIC12CXXX, PIC14C000, PIC16C5X, PIC16CXXX and PIC17CXX devices with up to 40 pins. Larger pin count devices such as the PIC16C923, PIC16C924 and PIC17C756 may be supported with an adapter socket. PICSTART Plus is CE compliant. The PICMASTER Emulator System has been designed as a real-time emulation system with advanced features that are generally found on more expensive development tools. The PC compatible 386 (and higher) machine platform and Microsoft Windows 3.x environment were chosen to best make these features available to you, the end user. PICSTART Plus Entry Level Development System The PICSTART programmer is an easy-to-use, low-cost prototype programmer. It connects to the PC via one of the COM (RS-232) ports. MPLAB Integrated Development Environment software makes using the programmer simple and efficient. PICSTART Plus is not recommended for production programming. A CE compliant version of PICMASTER is available for European Union (EU) countries. 1998 Microchip Technology Inc. DS30430C-page 71 PIC16F8X 10.6 PICDEM-1 Low-Cost PICmicro Demonstration Board The PICDEM-1 is a simple board which demonstrates the capabilities of several of Microchip's microcontrollers. The microcontrollers supported are: PIC16C5X (PIC16C54 to PIC16C58A), PIC16C61, PIC16C62X, PIC16C71, PIC16C8X, PIC17C42, PIC17C43 and PIC17C44. All necessary hardware and software is included to run basic demo programs. The users can program the sample microcontrollers provided with the PICDEM-1 board, on a PRO MATE II or PICSTART-Plus programmer, and easily test firmware. The user can also connect the PICDEM-1 board to the PICMASTER emulator and download the firmware to the emulator for testing. Additional prototype area is available for the user to build some additional hardware and connect it to the microcontroller socket(s). Some of the features include an RS-232 interface, a potentiometer for simulated analog input, push-button switches and eight LEDs connected to PORTB. 10.7 PICDEM-2 Low-Cost PIC16CXX Demonstration Board The PICDEM-2 is a simple demonstration board that supports the PIC16C62, PIC16C64, PIC16C65, PIC16C73 and PIC16C74 microcontrollers. All the necessary hardware and software is included to run the basic demonstration programs. The user can program the sample microcontrollers provided with the PICDEM-2 board, on a PRO MATE II programmer or PICSTART-Plus, and easily test firmware. The PICMASTER emulator may also be used with the PICDEM-2 board to test firmware. Additional prototype area has been provided to the user for adding additional hardware and connecting it to the microcontroller socket(s). Some of the features include a RS-232 interface, push-button switches, a potentiometer for simulated analog input, a Serial EEPROM to demonstrate usage of the I2C bus and separate headers for connection to an LCD module and a keypad. 10.8 PICDEM-3 Low-Cost PIC16CXXX Demonstration Board The PICDEM-3 is a simple demonstration board that supports the PIC16C923 and PIC16C924 in the PLCC package. It will also support future 44-pin PLCC microcontrollers with a LCD Module. All the necessary hardware and software is included to run the basic demonstration programs. The user can program the sample microcontrollers provided with the PICDEM-3 board, on a PRO MATE II programmer or PICSTART Plus with an adapter socket, and easily test firmware. The PICMASTER emulator may also be used with the PICDEM-3 board to test firmware. Additional prototype area has been provided to the user for adding hardware and connecting it to the microcontroller socket(s). Some of the features include DS30430C-page 72 an RS-232 interface, push-button switches, a potentiometer for simulated analog input, a thermistor and separate headers for connection to an external LCD module and a keypad. Also provided on the PICDEM-3 board is an LCD panel, with 4 commons and 12 segments, that is capable of displaying time, temperature and day of the week. The PICDEM-3 provides an additional RS-232 interface and Windows 3.1 software for showing the demultiplexed LCD signals on a PC. A simple serial interface allows the user to construct a hardware demultiplexer for the LCD signals. 10.9 MPLABTM Integrated Development Environment Software The MPLAB IDE Software brings an ease of software development previously unseen in the 8-bit microcontroller market. MPLAB is a windows based application which contains: * A full featured editor * Three operating modes - editor - emulator - simulator * A project manager * Customizable tool bar and key mapping * A status bar with project information * Extensive on-line help MPLAB allows you to: * Edit your source files (either assembly or `C') * One touch assemble (or compile) and download to PICmicro tools (automatically updates all project information) * Debug using: - source files - absolute listing file * Transfer data dynamically via DDE (soon to be replaced by OLE) * Run up to four emulators on the same PC The ability to use MPLAB with Microchip's simulator allows a consistent platform and the ability to easily switch from the low cost simulator to the full featured emulator with minimal retraining due to development tools. 10.10 Assembler (MPASM) The MPASM Universal Macro Assembler is a PC-hosted symbolic assembler. It supports all microcontroller series including the PIC12C5XX, PIC14000, PIC16C5X, PIC16CXXX, and PIC17CXX families. MPASM offers full featured Macro capabilities, conditional assembly, and several source and listing formats. It generates various object code formats to support Microchip's development tools as well as third party programmers. MPASM allows full symbolic debugging from PICMASTER, Microchip's Universal Emulator System. 1998 Microchip Technology Inc. PIC16F8X MPASM has the following features to assist in developing software for specific use applications. * Provides translation of Assembler source code to object code for all Microchip microcontrollers. * Macro assembly capability. * Produces all the files (Object, Listing, Symbol, and special) required for symbolic debug with Microchip's emulator systems. * Supports Hex (default), Decimal and Octal source and listing formats. MPASM provides a rich directive language to support programming of the PICmicro. Directives are helpful in making the development of your assemble source code shorter and more maintainable. 10.11 Software Simulator (MPLAB-SIM) The MPLAB-SIM Software Simulator allows code development in a PC host environment. It allows the user to simulate the PICmicro series microcontrollers on an instruction level. On any given instruction, the user may examine or modify any of the data areas or provide external stimulus to any of the pins. The input/output radix can be set by the user and the execution can be performed in; single step, execute until break, or in a trace mode. MPLAB-SIM fully supports symbolic debugging using MPLAB-C and MPASM. The Software Simulator offers the low cost flexibility to develop and debug code outside of the laboratory environment making it an excellent multi-project software development tool. 10.12 C Compiler (MPLAB-C17) 10.14 MP-DriveWay - Application Code Generator MP-DriveWay is an easy-to-use Windows-based Application Code Generator. With MP-DriveWay you can visually configure all the peripherals in a PICmicro device and, with a click of the mouse, generate all the initialization and many functional code modules in C language. The output is fully compatible with Microchip's MPLAB-C C compiler. The code produced is highly modular and allows easy integration of your own code. MP-DriveWay is intelligent enough to maintain your code through subsequent code generation. 10.15 SEEVAL Evaluation and Programming System The SEEVAL SEEPROM Designer's Kit supports all Microchip 2-wire and 3-wire Serial EEPROMs. The kit includes everything necessary to read, write, erase or program special features of any Microchip SEEPROM product including Smart Serials and secure serials. The Total Endurance Disk is included to aid in trade-off analysis and reliability calculations. The total kit can significantly reduce time-to-market and result in an optimized system. 10.16 KEELOQ Evaluation and Programming Tools KEELOQ evaluation and programming tools support Microchips HCS Secure Data Products. The HCS evaluation kit includes an LCD display to show changing codes, a decoder to decode transmissions, and a programming interface to program test transmitters. The MPLAB-C Code Development System is a complete `C' compiler and integrated development environment for Microchip's PIC17CXXX family of microcontrollers. The compiler provides powerful integration capabilities and ease of use not found with other compilers. For easier source level debugging, the compiler provides symbol information that is compatible with the MPLAB IDE memory display. 10.13 Fuzzy Logic Development System (fuzzyTECH-MP) fuzzyTECH-MP fuzzy logic development tool is available in two versions - a low cost introductory version, MP Explorer, for designers to gain a comprehensive working knowledge of fuzzy logic system design; and a full-featured version, fuzzyTECH-MP, Edition for implementing more complex systems. Both versions include Microchip's fuzzyLAB demonstration board for hands-on experience with fuzzy logic systems implementation. 1998 Microchip Technology Inc. DS30430C-page 73 Emulator Products Software Tools PIC16CXXX a a a a a a a a a a a a a a a a a a a a a a a PIC16C6X PIC16C7XX PIC16C8X PIC16C9XX PIC17C4X MPLAB C17 Compiler fuzzyTECH-MP Explorer/Edition Fuzzy Logic Dev. Tool a a MP-DriveWay Applications Code Generator PIC17C75X a a a a a a a a a a a a a a a a a a a a Programmers Total Endurance Software Model PICSTARTPlus Low-Cost Universal Dev. Kit PRO MATE II Universal Programmer KEELOQ Programmer Demo Boards 1998 Microchip Technology Inc. PICDEM-2 PICDEM-3 KEELOQ Evaluation Kit HCS200 HCS300 HCS301 a a a a a a a a a a a a a a a a a a a a a a a a SEEVAL Designers Kit PICDEM-1 24CXX 25CXX 93CXX a a a a a a a a a PIC16F8X MPLAB Integrated Development Environment PIC16C5X DEVELOPMENT TOOLS FROM MICROCHIP ICEPIC Low-Cost In-Circuit Emulator PIC14000 TABLE 10-1: DS30430C-page 74 PICMASTER/ PICMASTER-CE In-Circuit Emulator PIC12C5XX PIC16F83/84 11.0 PIC16F8X ELECTRICAL CHARACTERISTICS FOR PIC16F83 AND PIC16F84 Absolute Maximum Ratings Ambient temperature under bias.............................................................................................................-55C to +125C Storage temperature .............................................................................................................................. -65C to +150C Voltage on VDD with respect to VSS ........................................................................................................... -0.3 to +7.5V Voltage on MCLR with respect to VSS(2) .......................................................................................................-0.3 to +14V Voltage on any pin with respect to VSS (except VDD and MCLR).................................................... -0.6V to (VDD + 0.6V) Total power dissipation(1) .....................................................................................................................................800 mW Maximum current out of VSS pin ...........................................................................................................................150 mA Maximum current into VDD pin ..............................................................................................................................100 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 any I/O pin..........................................................................................................25 mA Maximum output current sourced by any I/O pin ....................................................................................................20 mA Maximum current sunk by PORTA ..........................................................................................................................80 mA Maximum current sourced by PORTA .....................................................................................................................50 mA Maximum current sunk by PORTB........................................................................................................................150 mA Maximum current sourced by PORTB...................................................................................................................100 mA Note 1: Power dissipation is calculated as follows: Pdis = VDD x {IDD - IOH} + {(VDD-VOH) x IOH} + (VOl x IOL) Note 2: Voltage spikes below VSS at the MCLR pin, inducing currents greater than 80 mA, may cause latch-up. Thus, a series resistor of 50-100 should be used when applying a "low" level to the MCLR pin rather than pulling this pin directly to VSS. 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. 1998 Microchip Technology Inc. DS30430C-page 75 PIC16F8X TABLE 11-1 PIC16F83/84 CROSS REFERENCE OF DEVICE SPECS FOR OSCILLATOR CONFIGURATIONS AND FREQUENCIES OF OPERATION (COMMERCIAL DEVICES) PIC16F84-04 PIC16F83-04 OSC PIC16F84-10 PIC16F83-10 PIC16LF84-04 PIC16LF83-04 RC VDD: IDD: IPD: Freq: 4.0V to 6.0V 4.5 mA max. at 5.5V 14 A max. at 4V WDT dis 4.0 MHz max. VDD: IDD: IPD: Freq: 4.5V to 5.5V 1.8 mA typ. at 5.5V 1.0 A typ. at 5.5V WDT dis 4..0 MHz max. VDD: IDD: IPD: Freq: 2.0V to 6.0V 4.5 mA max. at 5.5V 7.0 A max. at 2V WDT dis 2.0 MHz max. XT VDD: IDD: IPD: Freq: 4.0V to 6.0V 4.5 mA max. at 5.5V 14 A max. at 4V WDT dis 4.0 MHz max. VDD: IDD: IPD: Freq: 4.5V to 5.5V 1.8 mA typ. at 5.5V 1.0 A typ. at 5.5V WDT dis 4.0 MHz max. VDD: IDD: IPD: Freq: 2.0V to 6.0V 4.5 mA max. at 5.5V 7.0 A max. at 2V WDT dis 2.0 MHz max. HS VDD: 4.5V to 5.5V VDD: 4.5V to 5.5V IDD: 4.5 mA typ. at 5.5V IDD: 10 mA max. at 5.5V typ. IPD: 1.0 A typ. at 4.5V WDT dis IPD: 1.0 A typ. at 4.5V WDT dis Freq: 4.0 MHz max. LP VDD: IDD: IPD: Freq: 4.0V to 6.0V 48 A typ. at 32 kHz, 2.0V 0.6 A typ. at 3.0V WDT dis 200 kHz max. Do not use in HS mode Freq: 10 MHz max. Do not use in LP mode VDD: IDD: IPD: Freq: 2.0V to 6.0V 45 A max. at 32 kHz, 2.0V 7 A max. at 2.0V WDT dis 200 kHz max. The shaded sections indicate oscillator selections which are tested for functionality, but not for MIN/MAX specifications. It is recommended that the user select the device type that ensures the specifications required. DS30430C-page 76 1998 Microchip Technology Inc. PIC16F83/84 11.1 DC CHARACTERISTICS: DC Characteristics Power Supply Pins Parameter No. Sym Characteristic D001 D001A D002 VDD Supply Voltage VDR D003 VPOR D004 SVDD RAM Data Retention Voltage(1) VDD start voltage to ensure internal Power-on Reset signal VDD rise rate to ensure internal Power-on Reset signal Supply Current(2) IDD D010 D010A PIC16F8X PIC16F84, PIC16F83 (Commercial, Industrial) Standard Operating Conditions (unless otherwise stated) Operating temperature 0C TA +70C (commercial) -40C TA +85C (industrial) Min Typ Max Units Conditions 4.0 4.5 1.5* -- -- -- 6.0 5.5 -- V V V XT, RC and LP osc configuration HS osc configuration Device in SLEEP mode -- VSS -- V See section on Power-on Reset for details 0.05* -- -- -- -- 1.8 7.3 4.5 10 V/ms See section on Power-on Reset for details mA mA RC and XT osc configuration(4) FOSC = 4.0 MHz, VDD = 5.5V FOSC = 4.0 MHz, VDD = 5.5V (During Flash programming) HS osc configuration (PIC16F84-10) FOSC = 10 MHz, VDD = 5.5V VDD = 4.0V, WDT enabled, industrial VDD = 4.0V, WDT disabled, commercial VDD = 4.0V, WDT disabled, industrial -- 5 10 mA D013 D020 IPD Power-down Current(3) -- 7.0 28 A D021 -- 1.0 14 A D021A -- 1.0 16 A * These parameters are characterized but not tested. Data in "Typ" column is at 5.0V, 25C unless otherwise stated. These parameters are for design guidance only and are not tested. Note 1: This is the limit to which VDD can be lowered in SLEEP mode without losing RAM data. 2: The supply current is mainly a function of the operating voltage and frequency. Other factors such as I/O pin loading and switching rate, oscillator type, 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 tristated, pulled to VDD, T0CKI = VDD, MCLR = VDD; WDT enabled/disabled as specified. 3: 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 hi-impedance state and tied to VDD and VSS. 4: For RC osc configuration, current through Rext is not included. The current through the resistor can be estimated by the formula IR = VDD/2Rext (mA) with Rext in kOhm. 1998 Microchip Technology Inc. DS30430C-page 77 PIC16F8X 11.2 DC CHARACTERISTICS: PIC16F83/84 PIC16LF84, PIC16LF83 (Commercial, Industrial) DC Characteristics Power Supply Pins Parameter No. Sym D001 D002 VDD VDR D003 VPOR D004 SVDD IDD Characteristic Supply Voltage RAM Data Retention Voltage(1) VDD start voltage to ensure internal Power-on Reset signal VDD rise rate to ensure internal Power-on Reset signal Supply Current(2) Standard Operating Conditions (unless otherwise stated) Operating temperature 0C TA +70C (commercial) -40C TA +85C (industrial) Min Typ Max Units Conditions 2.0 1.5* -- -- 6.0 -- V V XT, RC, and LP osc configuration Device in SLEEP mode -- VSS -- V See section on Power-on Reset for details 0.05* -- -- V/ms See section on Power-on Reset for details D010 D010A -- -- 1 7.3 4 10 mA mA D014 -- 15 45 A RC and XT osc configuration(4) FOSC = 2.0 MHz, VDD = 5.5V FOSC = 2.0 MHz, VDD = 5.5V (During Flash programming) LP osc configuration FOSC = 32 kHz, VDD = 2.0V, WDT disabled VDD = 2.0V, WDT enabled, industrial VDD = 2.0V, WDT disabled, commercial VDD = 2.0V, WDT disabled, industrial Power-down Current(3) -- 3.0 16 A D020 IPD -- 0.4 7.0 A D021 -- 0.4 9.0 A D021A * These parameters are characterized but not tested. Data in "Typ" column is at 5.0V, 25C unless otherwise stated. These parameters are for design guidance only and are not tested. Note 1: This is the limit to which VDD can be lowered in SLEEP mode without losing RAM data. 2: The supply current is mainly a function of the operating voltage and frequency. Other factors such as I/O pin loading and switching rate, oscillator type, 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 tristated, pulled to VDD, T0CKI = VDD, MCLR = VDD; WDT enabled/disabled as specified. 3: 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 hi-impedance state and tied to VDD and VSS. 4: For RC osc configuration, current through Rext is not included. The current through the resistor can be estimated by the formula IR = VDD/2Rext (mA) with Rext in kOhm. DS30430C-page 78 1998 Microchip Technology Inc. PIC16F8X PIC16F83/84 11.3 DC CHARACTERISTICS: PIC16F84, PIC16F83 (Commercial, Industrial) PIC16LF84, PIC16LF83 (Commercial, Industrial) Standard Operating Conditions (unless otherwise stated) Operating temperature 0C TA +70C (commercial) -40C TA +85C (industrial) Operating voltage VDD range as described in DC spec Section 11.1 and Section 11.2. DC Characteristics All Pins Except Power Supply Pins Parameter No. Sym VIL D030 D030A D031 D032 D033 D034 VIH D040 D040A D041 D042 D043 D050 VHYS D070 IPURB D060 IIL Characteristic Input Low Voltage I/O ports with TTL buffer with Schmitt Trigger buffer MCLR, RA4/T0CKI OSC1 (XT, HS and LP modes)(1) OSC1 (RC mode) Input High Voltage I/O ports with TTL buffer Typ Max Units VSS VSS VSS Vss Vss Vss -- 0.8 0.16VDD 0.2VDD 0.2VDD 0.3VDD 0.1VDD V V V V V V 4.5 V VDD 5.5 V(4) entire range(4) entire range VDD VDD VDD VDD V V 4.5 V VDD 5.5V(4) entire range(4) entire range VDD -- V V 400* A VDD = 5.0V, VPIN = VSS 1 A 5 5 A A Vss VPIN VDD, Pin at hi-impedance Vss VPIN VDD Vss VPIN VDD, XT, HS and LP osc configuration -- -- -- -- -- Conditions -- -- 2.4 -- 0.48VDD -- with Schmitt Trigger buffer 0.45VDD -- MCLR, RA4/T0CKI, OSC1 0.85 (RC mode) VDD -- OSC1 (XT, HS and LP modes)(1) 0.7 VDD -- Hysteresis of TBD Schmitt Trigger inputs PORTB weak pull-up current 50* 250* Input Leakage Current(2,3) -- -- I/O ports MCLR, RA4/T0CKI OSC1 D061 D063 Min -- -- -- -- V Output Low Voltage -- -- I/O ports 0.6 V IOL = 8.5 mA, VDD = 4.5V -- -- OSC2/CLKOUT 0.6 V IOL = 1.6 mA, VDD = 4.5V Output High Voltage -- -- D090 VOH I/O ports(3) VDD-0.7 V IOH = -3.0 mA, VDD = 4.5V -- -- D092 OSC2/CLKOUT VDD-0.7 V IOH = -1.3 mA, VDD = 4.5V * These parameters are characterized but not tested. Data in "Typ" column is at 5.0V, 25C unless otherwise stated. These parameters are for design guidance only and are not tested. Note 1: In RC oscillator configuration, the OSC1 pin is a Schmitt Trigger input. Do not drive the PIC16F8X with an external clock while the device is in RC mode, or chip damage may result. 2: The leakage current on the MCLR pin is strongly dependent on the applied voltage level. The specified levels represent normal operating conditions. Higher leakage current may be measured at different input voltages. 3: Negative current is defined as coming out of the pin. 4: The user may choose the better of the two specs. D080 D083 VOL 1998 Microchip Technology Inc. DS30430C-page 79 PIC16F8X 11.4 PIC16F83/84 DC CHARACTERISTICS: PIC16F84, PIC16F83 (Commercial, Industrial) PIC16LF84, PIC16F83 (Commercial, Industrial) DC Characteristics All Pins Except Power Supply Pins Sym Characteristic D100 COSC2 Capacitive Loading Specs on Output Pins OSC2 pin D101 CIO Parameter No. D120 D121 ED VDRW D122 TDEW D130 D131 EP VPR All I/O pins and OSC2 (RC mode) Data EEPROM Memory Endurance VDD for read/write Erase/Write cycle time Program Flash Memory Endurance VDD for read Standard Operating Conditions (unless otherwise stated) Operating temperature 0C TA +70C (commercial) -40C TA +85C (industrial) Operating voltage VDD range as described in DC spec Section 11.1 and Section 11.2. Min Typ Max Units Conditions -- -- 15 pF -- -- 50 pF 1M VMIN 10M -- -- 6.0 E/W V -- 10 20* ms 100 VMIN 1000 -- -- 6.0 E/W V In XT, HS and LP modes when external clock is used to drive OSC1. 25C at 5V VMIN = Minimum operating voltage VMIN = Minimum operating voltage -- D132 VPEW VDD for erase/write 4.5 5.5 V D133 TPEW Erase/Write cycle time -- 10 -- ms * These parameters are characterized but not tested. Data in "Typ" column is at 5.0V, 25C unless otherwise stated. These parameters are for design guidance only and are not tested. DS30430C-page 80 1998 Microchip Technology Inc. PIC16F8X PIC16F83/84 TABLE 11-2 TIMING PARAMETER SYMBOLOGY The timing parameter symbols have been created following one of the following formats: 1. TppS2ppS 2. TppS T F Frequency Lowercase symbols (pp) and their meanings: pp 2 to ck CLKOUT cy cycle time io I/O port inp INT pin mc MCLR Uppercase symbols and their meanings: S F Fall H High I Invalid (Hi-impedance) L Low T Time os,osc ost pwrt rbt t0 wdt OSC1 oscillator start-up timer power-up timer RBx pins T0CKI watchdog timer P R V Z Period Rise Valid High Impedance FIGURE 11-1: PARAMETER MEASUREMENT INFORMATION All timings are measure between high and low measurement points as indicated in the figures below. 0.7 VDD XTAL 0.8 VDD RC (High) 0.9 VDD (High) 0.3 VDD XTAL 0.15 VDD RC (Low) OSC1 Measurement Points 0.1 VDD (Low) I/O Port Measurement Points FIGURE 11-2: LOAD CONDITIONS Load Condition 1 Load Condition 2 VDD/2 RL CL Pin CL Pin VSS VSS RL = 464 CL = 50 pF for all pins except OSC2. 15 pF for OSC2 output. 1998 Microchip Technology Inc. DS30430C-page 81 PIC16F8X 11.5 PIC16F83/84 Timing Diagrams and Specifications FIGURE 11-3: EXTERNAL CLOCK TIMING Q4 Q1 Q3 Q2 Q4 Q1 OSC1 1 3 3 4 4 2 CLKOUT TABLE 11-3 Parameter No. EXTERNAL CLOCK TIMING REQUIREMENTS Sym FOSC 1 Tosc Characteristic Min Typ Max Units External CLKIN Frequency(1) DC DC DC DC -- -- -- -- 2 4 10 200 MHz MHz MHz kHz XT, RC osc XT, RC osc HS osc LP osc PIC16LF8X-04 PIC16F8X-04 PIC16F8X-10 PIC16LF8X-04 Oscillator Frequency(1) DC DC 0.1 0.1 1.0 DC -- -- -- -- -- -- 2 4 2 4 10 200 MHz MHz MHz MHz MHz kHz RC osc RC osc XT osc XT osc HS osc LP osc PIC16LF8X-04 PIC16F8X-04 PIC16LF8X-04 PIC16F8X-04 PIC16F8X-10 PIC16LF8X-04 External CLKIN Period(1) 500 250 100 5.0 -- -- -- -- -- -- -- -- ns ns ns s XT, RC osc XT, RC osc HS osc LP osc PIC16LF8X-04 PIC16F8X-04 PIC16F8X-10 PIC16LF8X-04 Oscillator Period(1) 500 250 500 250 100 5.0 -- -- -- -- -- -- -- -- 10,000 10,000 1,000 -- ns ns ns ns ns s RC osc RC osc XT osc XT osc HS osc LP osc PIC16LF8X-04 PIC16F8X-04 PIC16LF8X-04 PIC16F8X-04 PIC16F8X-10 PIC16LF8X-04 0.4 60 * 50 * 2.0 * 35 * 25 * 50 * 15 * 4/Fosc -- -- -- -- -- -- -- DC -- -- -- -- -- -- -- s ns ns s ns ns ns ns XT osc XT osc LP osc HS osc XT osc LP osc HS osc PIC16LF8X-04 PIC16F8X-04 PIC16LF8X-04 PIC16F8X-10 PIC16F8X-04 PIC16LF8X-04 PIC16F8X-10 2 3 TCY TosL, TosH Instruction Cycle Time(1) Clock in (OSC1) High or Low Time 4 TosR, TosF Clock in (OSC1) Rise or Fall Time Conditions * These parameters are characterized but no tested. Data in "Typ" column is at 5.0V, 25C unless otherwise stated. These parameters are for design guidance only and are not tested. Note 1: Instruction cycle period (TCY) equals four times the input oscillator time-base period. 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 pin. When an external clock input is used, the "Max." cycle time limit is "DC" (no clock) for all devices. DS30430C-page 82 1998 Microchip Technology Inc. PIC16F8X PIC16F83/84 FIGURE 11-4: CLKOUT AND I/O TIMING Q1 Q4 Q2 Q3 OSC1 11 10 22 23 CLKOUT 13 19 14 12 18 16 I/O Pin (input) 15 17 I/O Pin (output) new value old value 20, 21 Note: All tests must be done with specified capacitive loads (Figure 11-2) 50 pF on I/O pins and CLKOUT. TABLE 11-4 Parameter No. 10 CLKOUT AND I/O TIMING REQUIREMENTS Sym Characteristic TosH2ckL OSC1 to CLKOUT TosH2ckH OSC1 to CLKOUT TckR CLKOUT rise time 10A 11 11A 12 12A 13 Min Typ Max PIC16F8X -- 15 30 * ns Note 1 PIC16LF8X -- 15 120 * ns Note 1 PIC16F8X -- 15 30 * ns Note 1 PIC16LF8X -- 15 120 * ns Note 1 PIC16F8X -- 15 30 * ns Note 1 PIC16LF8X -- 15 100 * ns Note 1 PIC16F8X -- 15 30 * ns Note 1 TckF CLKOUT fall time 14 TckL2ioV CLKOUT to Port out valid 15 TioV2ckH 13A PIC16LF8X Units Conditions -- 15 100 * ns Note 1 -- -- 0.5TCY +20 * ns Note 1 Port in valid before PIC16F8X 0.30TCY + 30 * -- -- ns Note 1 CLKOUT PIC16LF8X 0.30TCY + 80 * -- -- ns Note 1 Note 1 16 TckH2ioI Port in hold after CLKOUT 0* -- -- ns 17 TosH2ioV OSC1 (Q1 cycle) to PIC16F8X -- -- 125 * ns Port out valid PIC16LF8X -- -- 250 * ns 18 TosH2ioI OSC1 (Q2 cycle) to Port input invalid (I/O in hold time) PIC16F8X 10 * -- -- ns PIC16LF8X 10 * -- -- ns Port input valid to OSC1 (I/O in setup time) PIC16F8X -75 * -- -- ns PIC16LF8X -175 * -- -- ns Port output rise time PIC16F8X -- 10 35 * ns PIC16LF8X -- 10 70 * ns -- 10 35 * ns 19 20 TioV2osH TioR 20A 21 TioF Port output fall time PIC16F8X PIC16LF8X -- 10 70 * ns Tinp INT pin high PIC16F8X 20 * -- -- ns or low time PIC16LF8X 55 * -- -- ns RB7:RB4 change INT PIC16F8X TOSC -- -- ns high or low time PIC16LF8X TOSC -- -- ns 21A 22 22A 23 23A Trbp * These parameters are characterized but not tested. Data in "Typ" column is at 5.0V, 25C unless otherwise stated. These parameters are for design guidance only and are not tested. By design Note 1: Measurements are taken in RC Mode where CLKOUT output is 4 x TOSC. 1998 Microchip Technology Inc. DS30430C-page 83 PIC16F8X PIC16F83/84 FIGURE 11-5: RESET, WATCHDOG TIMER, OSCILLATOR START-UP TIMER AND POWER-UP TIMER TIMING VDD MCLR 30 Internal POR 33 PWRT Time-out 32 OSC Time-out Internal RESET Watchdog Timer RESET 31 34 34 I/O Pins TABLE 11-5 RESET, WATCHDOG TIMER, OSCILLATOR START-UP TIMER AND POWER-UP TIMER REQUIREMENTS Parameter No. Sym 30 TmcL MCLR Pulse Width (low) 31 Twdt Watchdog Timer Time-out Period (No Prescaler) * 32 Tost 33 Tpwrt 34 TIOZ Characteristic Min I/O Hi-impedance from MCLR Low or reset Max Units Conditions 1000 * -- -- ns 2.0V VDD 6.0V 7* 18 33 * ms VDD = 5.0V ms TOSC = OSC1 period 28 * 72 132 * ms VDD = 5.0V -- -- 100 * ns Oscillation Start-up Timer Period Power-up Timer Period Typ 1024TOSC These parameters are characterized but not tested. Data in "Typ" column is at 5V, 25C unless otherwise stated. These parameters are for design guidance only and are not tested. DS30430C-page 84 1998 Microchip Technology Inc. PIC16F8X PIC16F83/84 FIGURE 11-6: TIMER0 CLOCK TIMINGS RA4/T0CKI 40 41 42 TABLE 11-6 Parameter No. 40 TIMER0 CLOCK REQUIREMENTS Sym Characteristic Tt0H T0CKI High Pulse Width No Prescaler With Prescaler 41 Tt0L T0CKI Low Pulse Width No Prescaler With Prescaler 42 * Tt0P T0CKI Period Min Typ Max Units 0.5TCY + 20 * -- -- ns 50 * 30 * -- -- -- -- ns ns Conditions 2.0V VDD 3.0V 3.0V VDD 6.0V 0.5TCY + 20 * -- -- ns 50 * 20 * -- -- -- -- ns ns 2.0V VDD 3.0V 3.0V VDD 6.0V TCY + 40 * N -- -- ns N = prescale value (2, 4, ..., 256) These parameters are characterized but not tested. Data in "Typ" column is at 5.0V, 25C unless otherwise stated. These parameters are for design guidance only and are not tested. 1998 Microchip Technology Inc. DS30430C-page 85 PIC16F8X PIC16F83/84 NOTES: DS30430C-page 86 1998 Microchip Technology Inc. PIC16CR83/84 12.0 PIC16F8X ELECTRICAL CHARACTERISTICS FOR PIC16CR83 AND PIC16CR84 Absolute Maximum Ratings Ambient temperature under bias.............................................................................................................-55C to +125C Storage temperature .............................................................................................................................. -65C to +150C Voltage on VDD with respect to VSS ........................................................................................................... -0.3 to +7.5V Voltage on MCLR with respect to VSS(2) .......................................................................................................-0.3 to +14V Voltage on any pin with respect to VSS (except VDD and MCLR).................................................... -0.6V to (VDD + 0.6V) Total power dissipation(1) .....................................................................................................................................800 mW Maximum current out of VSS pin ...........................................................................................................................150 mA Maximum current into VDD pin ..............................................................................................................................100 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 any I/O pin..........................................................................................................25 mA Maximum output current sourced by any I/O pin ....................................................................................................20 mA Maximum current sunk by PORTA ..........................................................................................................................80 mA Maximum current sourced by PORTA .....................................................................................................................50 mA Maximum current sunk by PORTB........................................................................................................................150 mA Maximum current sourced by PORTB...................................................................................................................100 mA Note 1: Power dissipation is calculated as follows: Pdis = VDD x {IDD - IOH} + {(VDD-VOH) x IOH} + (VOl x IOL) Note 2: Voltage spikes below VSS at the MCLR pin, inducing currents greater than 80 mA, may cause latch-up. Thus, a series resistor of 50-100 should be used when applying a "low" level to the MCLR pin rather than pulling this pin directly to VSS. 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. 1998 Microchip Technology Inc. DS30430C-page 87 PIC16F8X TABLE 12-1 PIC16CR83/84 CROSS REFERENCE OF DEVICE SPECS FOR OSCILLATOR CONFIGURATIONS AND FREQUENCIES OF OPERATION (COMMERCIAL DEVICES) PIC16CR84-04 PIC16CR83-04 OSC PIC16CR84-10 PIC16CR83-10 PIC16LCR84-04 PIC16LCR83-04 RC VDD: IDD: IPD: Freq: 4.0V to 6.0V 4.5 mA max. at 5.5V 14 A max. at 4V WDT dis 4.0 MHz max. VDD: IDD: IPD: Freq: 4.5V to 5.5V 1.8 mA typ. at 5.5V 1.0 A typ. at 5.5V WDT dis 4..0 MHz max. VDD: IDD: IPD: Freq: 2.0V to 6.0V 4.5 mA max. at 5.5V 5 A max. at 2V WDT dis 2.0 MHz max. XT VDD: IDD: IPD: Freq: 4.0V to 6.0V 4.5 mA max. at 5.5V 14 A max. at 4V WDT dis 4.0 MHz max. VDD: IDD: IPD: Freq: 4.5V to 5.5V 1.8 mA typ. at 5.5V 1.0 A typ. at 5.5V WDT dis 4.0 MHz max. VDD: IDD: IPD: Freq: 2.0V to 6.0V 4.5 mA max. at 5.5V 5 A max. at 2V WDT dis 2.0 MHz max. HS VDD: 4.5V to 5.5V VDD: 4.5V to 5.5V IDD: 4.5 mA typ. at 5.5V IDD: 10 mA max. at 5.5V typ. IPD: 1.0 A typ. at 4.5V WDT dis IPD: 1.0 A typ. at 4.5V WDT dis Freq: 4.0 MHz max. LP VDD: IDD: IPD: Freq: 4.0V to 6.0V 48 A typ. at 32 kHz, 2.0V 0.6 A typ. at 3.0V WDT dis 200 kHz max. Do not use in HS mode Freq: 10 MHz max. Do not use in LP mode VDD: IDD: IPD: Freq: 2.0V to 6.0V 45 A max. at 32 kHz, 2.0V 5 A max. at 2V WDT dis 200 kHz max. The shaded sections indicate oscillator selections which are tested for functionality, but not for MIN/MAX specifications. It is recommended that the user select the device type that ensures the specifications required. DS30430C-page 88 1998 Microchip Technology Inc. PIC16CR83/84 12.1 DC CHARACTERISTICS: DC Characteristics Power Supply Pins Parameter No. Sym Characteristic D001 D001A D002 VDD Supply Voltage VDR D003 VPOR D004 SVDD RAM Data Retention Voltage(1) VDD start voltage to ensure internal Power-on Reset signal VDD rise rate to ensure internal Power-on Reset signal Supply Current(2) IDD D010 D010A PIC16F8X PIC16CR84, PIC16CR83 (Commercial, Industrial) Standard Operating Conditions (unless otherwise stated) Operating temperature 0C TA +70C (commercial) -40C TA +85C (industrial) Min Typ Max Units Conditions 4.0 4.5 1.5* -- -- 6.0 5.5 -- -- 0.05* -- -- -- V V V XT, RC and LP osc configuration HS osc configuration Device in SLEEP mode VSS -- V See section on Power-on Reset for details -- -- 1.8 7.3 4.5 10 V/ms See section on Power-on Reset for details mA mA RC and XT osc configuration(4) FOSC = 4.0 MHz, VDD = 5.5V FOSC = 4.0 MHz, VDD = 5.5V (During EEPROM programming) HS OSC CONFIGURATION (PIC16CR84-10) FOSC = 10 MHz, VDD = 5.5V VDD = 4.0V, WDT enabled, industrial VDD = 4.0V, WDT disabled, commercial VDD = 4.0V, WDT disabled, industrial -- 5 10 mA D013 (3) -- D020 IPD Power-down Current 7.0 28 A -- D021 1.0 14 A -- D021A 1.0 16 A * These parameters are characterized but not tested. Data in "Typ" column is at 5.0V, 25C unless otherwise stated. These parameters are for design guidance only and are not tested. Note 1: This is the limit to which VDD can be lowered in SLEEP mode without losing RAM data. 2: The supply current is mainly a function of the operating voltage and frequency. Other factors such as I/O pin loading and switching rate, oscillator type, 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 tristated, pulled to VDD, T0CKI = VDD, MCLR = VDD; WDT enabled/disabled as specified. 3: 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 hi-impedance state and tied to VDD and VSS. 4: For RC osc configuration, current through Rext is not included. The current through the resistor can be estimated by the formula IR = VDD/2Rext (mA) with Rext in kOhm. 1998 Microchip Technology Inc. DS30430C-page 89 PIC16F8X 12.2 PIC16CR83/84 DC CHARACTERISTICS: PIC16LCR84, PIC16LCR83 (Commercial, Industrial) DC Characteristics Power Supply Pins Parameter No. Sym D001 D002 VDD VDR D003 VPOR D004 SVDD IDD Characteristic Supply Voltage RAM Data Retention Voltage(1) VDD start voltage to ensure internal Power-on Reset signal VDD rise rate to ensure internal Power-on Reset signal Supply Current(2) Standard Operating Conditions (unless otherwise stated) Operating temperature 0C TA +70C (commercial) -40C TA +85C (industrial) Min Typ Max Units Conditions 2.0 1.5* -- -- 6.0 -- V V XT, RC, and LP osc configuration Device in SLEEP mode -- VSS -- V See section on Power-on Reset for details 0.05* -- -- V/ms See section on Power-on Reset for details D010 D010A -- -- 1 7.3 4 10 mA mA D014 -- 15 45 A RC and XT osc configuration(4) FOSC = 2.0 MHz, VDD = 5.5V FOSC = 2.0 MHz, VDD = 5.5V (During EEPROM programming) LP osc configuration FOSC = 32 kHz, VDD = 2.0V, WDT disabled VDD = 2.0V, WDT enabled, industrial VDD = 2.0V, WDT disabled, commercial VDD = 2.0V, WDT disabled, industrial Power-down Current(3) -- 3.0 16 A D020 IPD -- 0.4 5.0 A D021 -- 0.4 6.0 A D021A * These parameters are characterized but not tested. Data in "Typ" column is at 5.0V, 25C unless otherwise stated. These parameters are for design guidance only and are not tested. Note 1: This is the limit to which VDD can be lowered in SLEEP mode without losing RAM data. 2: The supply current is mainly a function of the operating voltage and frequency. Other factors such as I/O pin loading and switching rate, oscillator type, 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 tristated, pulled to VDD, T0CKI = VDD, MCLR = VDD; WDT enabled/disabled as specified. 3: 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 hi-impedance state and tied to VDD and VSS. 4: For RC osc configuration, current through Rext is not included. The current through the resistor can be estimated by the formula IR = VDD/2Rext (mA) with Rext in kOhm. DS30430C-page 90 1998 Microchip Technology Inc. PIC16F8X PIC16CR83/84 12.3 DC CHARACTERISTICS: PIC16CR84, PIC16CR83 (Commercial, Industrial) PIC16LCR84, PIC16LCR83 (Commercial, Industrial) Standard Operating Conditions (unless otherwise stated) Operating temperature 0C TA +70C (commercial) -40C TA +85C (industrial) Operating voltage VDD range as described in DC spec Section 12.1 and Section 12.2. DC Characteristics All Pins Except Power Supply Pins Parameter No. Sym Characteristic Min Typ Max Units Conditions VSS -- 0.8 V 4.5 V Vdd 5.5 V(4) VSS -- 0.16VDD V entire range(4) VSS -- entire range Input Low Voltage VIL D030 I/O ports with TTL buffer D030A D031 with Schmitt Trigger buffer 0.2VDD V D032 MCLR, RA4/T0CKI Vss -- 0.2VDD V D033 OSC1 (XT, HS and LP modes)(1) Vss -- 0.3VDD V D034 OSC1 (RC mode) Vss -- 0.1VDD V V V Input High Voltage VIH D040 D040A D041 I/O ports -- with TTL buffer 2.4 0.48VDD -- -- VDD VDD with Schmitt Trigger buffer 0.45VDD -- VDD 0.85 VDD -- VDD V D042 MCLR, RA4/T0CKI, OSC1 (RC mode) D043 OSC1 (XT, HS and LP modes)(1) 0.7 VDD -- 4.5 V VDD 5.5V(4) entire range(4) entire range VDD V D050 VHYS Hysteresis of Schmitt Trigger inputs TBD -- -- V D070 IPURB PORTB weak pull-up current 50* 250* 400* A VDD = 5.0V, VPIN = VSS I/O ports -- -- 1 A Vss VPIN VDD, Pin at hi-impedance D061 MCLR, RA4/T0CKI -- -- 5 A Vss VPIN VDD D063 OSC1 -- -- 5 A Vss VPIN VDD, XT, HS and LP osc configuration I/O ports -- -- 0.6 V IOL = 8.5 mA, VDD = 4.5V OSC2/CLKOUT -- -- 0.6 V IOL = 1.6 mA, VDD = 4.5V I/O ports(3) VDD-0.7 -- -- V IOH = -3.0 mA, VDD = 4.5V OSC2/CLKOUT VDD-0.7 -- -- V IOH = -1.3 mA, VDD = 4.5V Input Leakage Current(2,3) D060 IIL Output Low Voltage D080 VOL D083 Output High Voltage D090 D092 VOH * These parameters are characterized but not tested. Data in "Typ" column is at 5.0V, 25C unless otherwise stated. These parameters are for design guidance only and are not tested. Note 1: In RC oscillator configuration, the OSC1 pin is a Schmitt Trigger input. Do not drive the PIC16CR8X with an external clock while the device is in RC mode, or chip damage may result. 2: The leakage current on the MCLR pin is strongly dependent on the applied voltage level. The specified levels represent normal operating conditions. Higher leakage current may be measured at different input voltages. 3: Negative current is defined as coming out of the pin. 4: The user may choose the better of the two specs. 1998 Microchip Technology Inc. DS30430C-page 91 PIC16F8X 12.4 PIC16CR83/84 DC CHARACTERISTICS: PIC16CR84, PIC16CR83 (Commercial, Industrial) PIC16LCR84, PIC16LCR83 (Commercial, Industrial) DC Characteristics All Pins Except Power Supply Pins Sym Characteristic D100 COSC2 Capacitive Loading Specs on Output Pins OSC2 pin D101 CIO D120 D121 ED VDRW Parameter No. All I/O pins and OSC2 (RC mode) Data EEPROM Memory Endurance VDD for read/write Standard Operating Conditions (unless otherwise stated) Operating temperature 0C TA +70C (commercial) -40C TA +85C (industrial) Operating voltage VDD range as described in DC spec Section 12.1 and Section 12.2. Min Typ Max Units Conditions -- -- 15 pF -- -- 50 pF 1M VMIN 10M -- -- 6.0 E/W V In XT, HS and LP modes when external clock is used to drive OSC1. 25C at 5V VMIN = Minimum operating voltage -- 10 20* ms D122 TDEW Erase/Write cycle time * These parameters are characterized but not tested. Data in "Typ" column is at 5.0V, 25C unless otherwise stated. These parameters are for design guidance only and are not tested. DS30430C-page 92 1998 Microchip Technology Inc. PIC16F8X PIC16CR83/84 TABLE 12-2 TIMING PARAMETER SYMBOLOGY The timing parameter symbols have been created following one of the following formats: 1. TppS2ppS 2. TppS T F Frequency Lowercase symbols (pp) and their meanings: pp 2 to ck CLKOUT cy cycle time io I/O port inp INT pin mc MCLR Uppercase symbols and their meanings: S F Fall H High I Invalid (Hi-impedance) L Low T Time os,osc ost pwrt rbt t0 wdt OSC1 oscillator start-up timer power-up timer RBx pins T0CKI watchdog timer P R V Z Period Rise Valid High Impedance FIGURE 12-1: PARAMETER MEASUREMENT INFORMATION All timings are measure between high and low measurement points as indicated in the figures below. 0.7 VDD XTAL 0.8 VDD RC (High) 0.9 VDD (High) 0.3 VDD XTAL 0.15 VDD RC (Low) OSC1 Measurement Points 0.1 VDD (Low) I/O Port Measurement Points FIGURE 12-2: LOAD CONDITIONS Load Condition 1 Load Condition 2 VDD/2 RL CL Pin CL Pin VSS VSS RL = 464 CL = 50 pF for all pins except OSC2. 15 pF for OSC2 output. 1998 Microchip Technology Inc. DS30430C-page 93 PIC16F8X 12.5 PIC16CR83/84 Timing Diagrams and Specifications FIGURE 12-3: EXTERNAL CLOCK TIMING Q4 Q1 Q3 Q2 Q4 Q1 OSC1 1 3 3 4 4 2 CLKOUT TABLE 12-3 Parameter No. EXTERNAL CLOCK TIMING REQUIREMENTS Sym FOSC Characteristic External CLKIN Frequency(1) Oscillator Frequency 1 Tosc (1) External CLKIN Period(1) Oscillator Period (1) 2 TCY Instruction Cycle Time(1) 3 TosL, TosH Clock in (OSC1) High or Low Time 4 TosR, TosF Clock in (OSC1) Rise or Fall Time Min Typ Max Units Conditions DC -- 2 MHz XT, RC osc PIC16LCR8X-04 DC -- 4 MHz XT, RC osc PIC16CR8X-04 DC -- 10 MHz HS osc PIC16CR8X-10 DC -- 200 kHz LP osc PIC16LCR8X-04 DC -- 2 MHz RC osc PIC16LCR8X-04 DC -- 4 MHz RC osc PIC16CR8X-04 0.1 -- 2 MHz XT osc PIC16LCR8X-04 0.1 -- 4 MHz XT osc PIC16CR8X-04 1.0 -- 10 MHz HS osc PIC16CR8X-10 DC -- 200 kHz LP osc PIC16LCR8X-04 500 -- -- ns XT, RC osc PIC16LCR8X-04 250 -- -- ns XT, RC osc PIC16CR8X-04 100 -- -- ns HS osc PIC16CR8X-10 5.0 -- -- s LP osc PIC16LCR8X-04 500 -- -- ns RC osc PIC16LCR8X-04 250 -- -- ns RC osc PIC16CR8X-04 500 -- 10,000 ns XT osc PIC16LCR8X-04 250 -- 10,000 ns XT osc PIC16CR8X-04 100 -- 1,000 ns HS osc PIC16CR8X-10 5.0 -- -- s LP osc PIC16LCR8X-04 0.4 4/Fosc DC s 60 * -- -- ns XT osc PIC16LCR8X-04 50 * -- -- ns XT osc PIC16CR8X-04 2.0 * -- -- s LP osc PIC16LCR8X-04 35 * -- -- ns HS osc PIC16CR8X-10 PIC16CR8X-04 25 * -- -- ns XT osc 50 * -- -- ns LP osc PIC16LCR8X-04 15 * -- -- ns HS osc PIC16CR8X-10 * These parameters are characterized but not tested. Data in "Typ" column is at 5.0V, 25C unless otherwise stated. These parameters are for design guidance only and are not tested. Note 1: Instruction cycle period (TCY) equals four times the input oscillator time base period. 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 pin. When an external clock input is used, the "Max." cycle time limit is "DC" (no clock) for all devices. DS30430C-page 94 1998 Microchip Technology Inc. PIC16F8X PIC16CR83/84 FIGURE 12-4: CLKOUT AND I/O TIMING Q1 Q4 Q2 Q3 OSC1 11 10 22 23 CLKOUT 13 19 14 12 18 16 I/O Pin (input) 15 17 I/O Pin (output) new value old value 20, 21 Note: All tests must be done with specified capacitive loads (Figure 12-2) 50 pF on I/O pins and CLKOUT. TABLE 12-4 Parameter No. 10 CLKOUT AND I/O TIMING REQUIREMENTS Sym Characteristic TosH2ckL OSC1 to CLKOUT TosH2ckH OSC1 to CLKOUT TckR CLKOUT rise time 10A 11 11A 12 12A 13 PIC16CR8X Typ Max -- 15 30 * Units Conditions ns -- 15 120 * ns Note 1 PIC16CR8X -- 15 30 * ns Note 1 PIC16LCR8X -- 15 120 * ns Note 1 PIC16CR8X -- 15 30 * ns Note 1 PIC16LCR8X -- 15 100 * ns Note 1 PIC16CR8X -- 15 30 * ns Note 1 PIC16LCR8X -- 15 100 * ns Note 1 -- -- 0.5TCY +20 * ns Note 1 CLKOUT fall time 14 TckL2ioV CLKOUT to Port out valid 15 TioV2ckH Port in valid before PIC16CR8X 0.30TCY + 30 * -- -- ns Note 1 CLKOUT PIC16LCR8X 0.30TCY + 80 * -- -- ns Note 1 Note 1 16 TckH2ioI Port in hold after CLKOUT 0* -- -- ns 17 TosH2ioV OSC1 (Q1 cycle) to PIC16CR8X -- -- 125 * ns Port out valid PIC16LCR8X -- -- 250 * ns 18 TosH2ioI OSC1 (Q2 cycle) to Port input invalid (I/O in hold time) PIC16CR8X 10 * -- -- ns PIC16LCR8X 10 * -- -- ns Port input valid to OSC1 (I/O in setup time) PIC16CR8X -75 * -- -- ns PIC16LCR8X -175 * -- -- ns 19 20 TioV2osH TioR Port output rise time 20A 21 23A -- 10 35 * ns -- 10 70 * ns -- 10 35 * ns Port output fall time PIC16CR8X PIC16LCR8X -- 10 70 * ns Tinp INT pin high PIC16CR8X 20 * -- -- ns or low time PIC16LCR8X 55 * -- -- ns Trbp RB7:RB4 change INT PIC16CR8X TOSC -- -- ns high or low time PIC16LCR8X TOSC -- -- ns 22A 23 PIC16CR8X PIC16LCR8X TioF 21A 22 Note 1 PIC16LCR8X TckF 13A Min * These parameters are characterized but not tested. Data in "Typ" column is at 5.0V, 25C unless otherwise stated. These parameters are for design guidance only and are not tested. By design Note 1: Measurements are taken in RC Mode where CLKOUT output is 4 x TOSC. 1998 Microchip Technology Inc. DS30430C-page 95 PIC16F8X PIC16CR83/84 FIGURE 12-5: RESET, WATCHDOG TIMER, OSCILLATOR START-UP TIMER AND POWER-UP TIMER TIMING VDD MCLR 30 Internal POR 33 PWRT Time-out 32 OSC Time-out Internal RESET Watchdog Timer RESET 31 34 34 I/O Pins TABLE 12-5 Parameter No. * RESET, WATCHDOG TIMER, OSCILLATOR START-UP TIMER AND POWER-UP TIMER REQUIREMENTS Sym Characteristic 30 TmcL MCLR Pulse Width (low) 31 Twdt Watchdog Timer Time-out Period (No Prescaler) 32 Tost Oscillation Start-up Timer Period 33 Tpwrt Power-up Timer Period 34 TIOZ I/O Hi-impedance from MCLR Low or reset Min Typ Max Units Conditions 1000 * -- -- ns 2.0V VDD 6.0V 7* 18 33 * ms VDD = 5.0V ms TOSC = OSC1 period 28 * 72 132 * ms VDD = 5.0V -- -- 100 * ns 1024TOSC These parameters are characterized but not tested. Data in "Typ" column is at 5V, 25C unless otherwise stated. These parameters are for design guidance only and are not tested. DS30430C-page 96 1998 Microchip Technology Inc. PIC16F8X PIC16CR83/84 FIGURE 12-6: TIMER0 CLOCK TIMINGS RA4/T0CKI 40 41 42 TABLE 12-6 Parameter No. 40 TIMER0 CLOCK REQUIREMENTS Sym Tt0H Characteristic T0CKI High Pulse Width Min No Prescaler With Prescaler 41 Tt0L T0CKI Low Pulse Width No Prescaler With Prescaler 42 * Tt0P T0CKI Period Typ Max Units 0.5TCY + 20 * -- -- ns 50 * 30 * -- -- -- -- ns ns Conditions 2.0V VDD 3.0V 3.0V VDD 6.0V 0.5TCY + 20 * -- -- ns 50 * 20 * -- -- -- -- ns ns 2.0V VDD 3.0V 3.0V VDD 6.0V TCY + 40 * N -- -- ns N = prescale value (2, 4, ..., 256) These parameters are characterized but not tested. Data in "Typ" column is at 5.0V, 25C unless otherwise stated. These parameters are for design guidance only and are not tested. 1998 Microchip Technology Inc. DS30430C-page 97 PIC16F8X PIC16CR83/84 NOTES: DS30430C-page 98 1998 Microchip Technology Inc. PIC16F8X 13.0 DC & AC CHARACTERISTICS GRAPHS/TABLES The graphs and tables provided in this section are for design guidance and are not tested or guaranteed. In some graphs or tables, the data presented are outside specified operating range (i.e., outside specified VDD range). This is for information only and devices are guaranteed to operate properly only within the specified range. The data presented in this section is a statistical summary of data collected on units from different lots over a period of time and matrix samples. 'Typical' represents the mean of the distribution at 25C, while 'max' or 'min' represents (mean + 3) and (mean - 3) respectively, where is standard deviation. FIGURE 13-1: TYPICAL RC OSCILLATOR FREQUENCY vs. TEMPERATURE FOSC FOSC (25C) Frequency normalized to +25C 1.20 Rext = 10 k Cext = 100 pF 1.16 1.12 1.08 1.04 1.00 VDD = 5.5 V 0.96 0.92 VDD = 3.5 V 0.88 0.84 -40 -20 0 20 25 40 60 70 80 85 100 T(C) TABLE 13-1 RC OSCILLATOR FREQUENCIES* Cext Rext Average Fosc @ 5V, 25C Part to Part Variation 5k 4.61 MHz 25% 10 k 2.66 MHz 24% 100 k 311 kHz 39% 100 pF 5k 1.34 MHz 21% 10 k 756 kHz 18% 100 k 82.8 kHz 28% 300 pF 5k 428 kHz 13% 10 k 243 kHz 13% 100 k 26.2 kHz 23% * Measured on DIP packages. The percentage variation indicated here is part-to-part variation due to normal process distribution. The variation indicated is 3 standard deviation from average value for full VDD range. 20 pF 1998 Microchip Technology Inc. DS30430C-page 99 PIC16F8X FIGURE 13-2: TYPICAL RC OSCILLATOR FREQUENCY vs. VDD, CEXT = 20 PF Measured on DIP Packages, T = 25C 5.5 5.0 R = 5k 4.5 4.0 Fosc (MHz) 3.5 R = 10k 3.0 2.5 2.0 1.5 1.0 R = 100k 0.5 0.0 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 VDD (Volts) DS30430C-page 100 1998 Microchip Technology Inc. PIC16F8X FIGURE 13-3: TYPICAL RC OSCILLATOR FREQUENCY vs. VDD, CEXT = 100 PF Measured on DIP Packages, T = 25C 1.8 R = 5k 1.6 1.4 Fosc (MHz) 1.2 1.0 R = 10k 0.8 0.6 0.4 0.2 R = 100k 0.0 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 VDD (Volts) FIGURE 13-4: TYPICAL RC OSCILLATOR FREQUENCY vs. VDD, CEXT = 300 PF Measured on DIP Packages, T = 25C 0.6 R = 5k FOSC (MHz) 0.5 0.4 R = 10k 0.3 0.2 0.1 R = 100k 0.0 1998 Microchip Technology Inc. 2.0 2.5 3.0 3.5 4.0 4.5 VDD (Volts) 5.0 5.5 6.0 DS30430C-page 101 PIC16F8X FIGURE 13-5: TYPICAL IPD vs. VDD, WATCHDOG DISABLED FIGURE 13-6: TYPICAL IPD vs. VDD, WATCHDOG ENABLED 6.0 10 9 5.0 8 T = 25C T = 25C 7 6 IPD (A) IPD (A) 4.0 3.0 5 4 3 2 2.0 1 0 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 1.0 VDD (Volts) 0.0 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 VDD (Volts) FIGURE 13-7: VTH (INPUT THRESHOLD VOLTAGE) OF I/O PINS vs. VDD 1.40 VTH (Volts) 1.30 1.20 ( Typ 1.10 C +25 ) 1.00 0.90 0.80 0.70 2.0 2.5 3.0 3.5 4.0 VDD (Volts) 4.5 5.0 5.5 6.0 Note: These input pins have TTL input buffers. DS30430C-page 102 1998 Microchip Technology Inc. PIC16F8X FIGURE 13-8: VTH (INPUT THRESHOLD VOLTAGE) OF OSC1 INPUT (IN XT, HS, AND LP MODES) vs. VDD 3.0 2.8 2.6 VTH (Volts) 2.4 2.2 2.0 ( Typ 1.8 C) +25 1.6 1.4 1.2 1.0 0.8 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 5.5 6.0 VDD (Volts) Note: This input pin is CMOS input. FIGURE 13-9: VIH, VIL OF MCLR, T0CKI AND OSC1 (IN RC MODE) vs. VDD 5.0 4.5 4.0 VIH, VIL (Volts) 3.5 3.0 V IH ty p + 25C 2.5 2.0 1.5 VIL typ +25C 1.0 0.5 0.0 2.0 2.5 3.0 3.5 4.0 VDD (Volts) 4.5 5.0 Note: These input pins have Schmitt Trigger input buffers. 1998 Microchip Technology Inc. DS30430C-page 103 PIC16F8X FIGURE 13-10: TYPICAL IDD vs. FREQUENCY (RC MODE @20PF, 25C) TYPICAL IDD vs FREQ (RC MODE @20pF) 10000 1000 6.0V 5.5V 100 5.0V 4.5V 4.0V 3.5V 3.0V 2.5V 2.0V 10 100000 1000000 10000000 FREQ (Hz) DS30430C-page 104 1998 Microchip Technology Inc. PIC16F8X FIGURE 13-11: TYPICAL IDD vs. FREQUENCY (RC MODE @100PF, 25C) TYPICAL IDD vs FREQ (RC MODE @100 pF) 10000 1000 6.0V 5.5V 100 5.0V 4.5V 4.0V 3.5V 3.0V 2.5V 2.0V 10 10000 100000 1000000 10000000 FREQ (Hz) 1998 Microchip Technology Inc. DS30430C-page 105 PIC16F8X FIGURE 13-12: TYPICAL IDD vs. FREQUENCY (RC MODE @300PF, 25C) TYPICAL IDD vs FREQ (RC MODE @300pF) 1000 6.0V 5.5V 100 5.0V 4.5V 4.0V 3.5V 3.0V 2.5V 2.0V 10 10000 100000 1000000 FREQ (Hz) DS30430C-page 106 1998 Microchip Technology Inc. PIC16F8X FIGURE 13-14: TRANSCONDUCTANCE (gm) OF HS OSCILLATOR vs. VDD 50 9000 45 8000 40 7000 35 6000 30 5000 gm (A/V) WDT period (ms) FIGURE 13-13: WDT TIMER TIME-OUT PERIOD vs. VDD Typ +25C 25 Typ +25C 4000 20 3000 15 2000 10 100 5 2.0 3.0 4.0 VDD (Volts) 1998 Microchip Technology Inc. 5.0 6.0 0 2.0 3.0 4.0 5.0 VDD (Volts) 6.0 DS30430C-page 107 PIC16F8X FIGURE 13-15: TRANSCONDUCTANCE (gm) OF LP OSCILLATOR vs. VDD FIGURE 13-16: TRANSCONDUCTANCE (gm) OF XT OSCILLATOR vs. VDD 2500 45 40 2000 35 30 25 gm (A/V) gm (A/V) 1500 20 Typ +25C Typ +25C 1000 15 500 10 5 0 2.0 0 2.0 3.0 4.0 5.0 6.0 3.0 4.0 5.0 6.0 VDD (Volts) VDD (Volts) DS30430C-page 108 1998 Microchip Technology Inc. PIC16F8X FIGURE 13-19: IOL vs. VOL, VDD = 3 V FIGURE 13-17: IOH vs. VOH, VDD = 3 V 45 0 40 -5 35 30 -10 IOL (mA) IOH (mA) Typ +25C -15 25 Typ +25C 20 15 -20 10 5 -25 0.0 0.5 1.0 1.5 2.0 2.5 3.0 0 0.0 VOH (Volts) 0.5 1.0 1.5 2.0 2.5 3.0 VOL (Volts) FIGURE 13-18: IOH vs. VOH, VDD = 5 V FIGURE 13-20: IOL vs. VOL, VDD = 5 V 90 0 80 -5 70 -10 60 -20 Typ +25C IOL (mA) IOH (mA) -15 Typ +25C 50 40 -25 30 -30 20 -35 10 -40 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 VOH (Volts) 0 0.0 0.5 1.0 1.5 2.0 2.5 3.0 VOL (Volts) 1998 Microchip Technology Inc. DS30430C-page 109 PIC16F8X FIGURE 13-21: TYPICAL DATA MEMORY ERASE/WRITE CYCLE TIME VS. VDD 10 9 8 DMEM Typ. E/W Cycle Time (ms) 7 6 5 4 3 2 1 0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 VDD (Volts) Shaded area is beyond recommended range. TABLE 13-2 INPUT CAPACITANCE* Typical Capacitance (pF) Pin Name 18L PDIP 18L SOIC PORTA 5.0 4.3 PORTB 5.0 4.3 MCLR 17.0 17.0 OSC1/CLKIN 4.0 3.5 OSC2/CLKOUT 4.3 3.5 T0CKI 3.2 2.8 * All capacitance values are typical at 25C. A part to part variation of 25% (three standard deviations) should be taken into account. DS30430C-page 110 1998 Microchip Technology Inc. PIC16F8X 14.0 PACKAGING INFORMATION 14.1 Package Marking Information Example 18L PDIP XXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXX AABBCDE 18L SOIC PIC16F84-04I/P 9632SAW Example XXXXXXXXXXXX XXXXXXXXXXXX XXXXXXXXXXXX AABBCDE Legend: XX...X AA BB C D E PIC16F84-04 /SO 9648SAN Microchip part number & customer specific information* Year code (last two digits of calendar year) Week code (week of January 1 is week `01') Facility code of the plant at which wafer is manufactured C = Chandler, Arizona, U.S.A., S = Tempe, Arizona, U.S.A. Mask revision number Assembly code of the plant or country of origin in which part was assembled 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. Standard OTP marking consists of Microchip part number, year code, week code, facility code, mask rev# and assembly code. For OTP marking beyond this, certain price adders apply. Please check with your Microchip Sales Office. For QTP devices, any special marking adders are included in QTP price. 1998 Microchip Technology Inc. DS30430C-page 111 PIC16F8X Package Type: K04-007 18-Lead Plastic Dual In-line (P) - 300 mil E D 2 n 1 E1 A1 A R L c A2 B1 p B eB Units Dimension Limits PCB Row Spacing Number of Pins Pitch Lower Lead Width Upper Lead Width Shoulder Radius Lead Thickness Top to Seating Plane Top of Lead to Seating Plane Base to Seating Plane Tip to Seating Plane Package Length Molded Package Width Radius to Radius Width Overall Row Spacing Mold Draft Angle Top Mold Draft Angle Bottom INCHES* NOM 0.300 18 0.100 0.013 0.018 0.055 0.060 0.000 0.005 0.005 0.010 0.110 0.155 0.075 0.095 0.000 0.020 0.125 0.130 0.890 0.895 0.245 0.255 0.230 0.250 0.310 0.349 5 10 5 10 MIN n p B B1 R c A A1 A2 L D E E1 eB MAX 0.023 0.065 0.010 0.015 0.155 0.115 0.020 0.135 0.900 0.265 0.270 0.387 15 15 MILLIMETERS NOM MAX 7.62 18 2.54 0.33 0.46 0.58 1.40 1.52 1.65 0.00 0.13 0.25 0.13 0.25 0.38 2.79 3.94 3.94 1.91 2.41 2.92 0.00 0.51 0.51 3.18 3.30 3.43 22.61 22.73 22.86 6.22 6.48 6.73 5.84 6.35 6.86 7.87 8.85 9.83 5 10 15 5 10 15 MIN * Controlling Parameter. Dimension "B1" does not include dam-bar protrusions. Dam-bar protrusions shall not exceed 0.003" (0.076 mm) per side or 0.006" (0.152 mm) more than dimension "B1." Dimensions "D" and "E" do not include mold flash or protrusions. Mold flash or protrusions shall not exceed 0.010" (0.254 mm) per side or 0.020" (0.508 mm) more than dimensions "D" or "E." DS30430C-page 112 1998 Microchip Technology Inc. PIC16F8X Package Type: K04-051 18-Lead Plastic Small Outline (SO) - Wide, 300 mil E1 p E D 2 B 1 n X 45 L R2 c A R1 Units Dimension Limits Pitch Number of Pins Overall Pack. Height Shoulder Height Standoff Molded Package Length Molded Package Width Outside Dimension Chamfer Distance Shoulder Radius Gull Wing Radius Foot Length Foot Angle Radius Centerline Lead Thickness Lower Lead Width Mold Draft Angle Top Mold Draft Angle Bottom L1 p n A A1 A2 D E E1 X R1 R2 L L1 c B A2 INCHES* NOM 0.050 18 0.093 0.099 0.048 0.058 0.004 0.008 0.450 0.456 0.292 0.296 0.394 0.407 0.010 0.020 0.005 0.005 0.005 0.005 0.011 0.016 0 4 0.010 0.015 0.009 0.011 0.014 0.017 0 12 0 12 MIN A1 MAX 0.104 0.068 0.011 0.462 0.299 0.419 0.029 0.010 0.010 0.021 8 0.020 0.012 0.019 15 15 MILLIMETERS NOM MAX 1.27 18 2.36 2.64 2.50 1.22 1.73 1.47 0.10 0.28 0.19 11.43 11.73 11.58 7.42 7.59 7.51 10.01 10.64 10.33 0.74 0.25 0.50 0.13 0.25 0.13 0.13 0.13 0.25 0.28 0.53 0.41 0 4 8 0.25 0.38 0.51 0.23 0.27 0.30 0.36 0.48 0.42 0 12 15 0 12 15 MIN * Controlling Parameter. Dimension "B" does not include dam-bar protrusions. Dam-bar protrusions shall not exceed 0.003" (0.076 mm) per side or 0.006" (0.152 mm) more than dimension "B." Dimensions "D" and "E" do not include mold flash or protrusions. Mold flash or protrusions shall not exceed 0.010" (0.254 mm) per side or 0.020" (0.508 mm) more than dimensions "D" or "E." 1998 Microchip Technology Inc. DS30430C-page 113 PIC16F8X NOTES: DS30430C-page 114 1998 Microchip Technology Inc. PIC16F8X APPENDIX A: FEATURE IMPROVEMENTS FROM PIC16C5X TO PIC16F8X The following is the list of feature improvements over the PIC16C5X microcontroller family: 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. Instruction word length is increased to 14 bits. This allows larger page sizes both in program memory (2K now as opposed to 512 before) and the register file (128 bytes now versus 32 bytes before). A PC latch register (PCLATH) is added to handle program memory paging. PA2, PA1 and PA0 bits are removed from the status register and placed in the option register. Data memory paging is redefined slightly. The STATUS register is modified. Four new instructions have been added: RETURN, RETFIE, ADDLW, and SUBLW. Two instructions, TRIS and OPTION, are being phased out although they are kept for compatibility with PIC16C5X. OPTION and TRIS registers are made addressable. Interrupt capability is added. Interrupt vector is at 0004h. Stack size is increased to 8 deep. Reset vector is changed to 0000h. Reset of all registers is revisited. Five different reset (and wake-up) types are recognized. Registers are reset differently. Wake up from SLEEP through interrupt is added. Two separate timers, the Oscillator Start-up Timer (OST) and Power-up Timer (PWRT), are included for more reliable power-up. These timers are invoked selectively to avoid unnecessary delays on power-up and wake-up. PORTB has weak pull-ups and interrupt on change features. T0CKI pin is also a port pin (RA4/T0CKI). FSR is a full 8-bit register. "In system programming" is made possible. The user can program PIC16CXX devices using only five pins: VDD, VSS, VPP, RB6 (clock) and RB7 (data in/out). 1998 Microchip Technology Inc. APPENDIX B: CODE COMPATIBILITY - FROM PIC16C5X TO PIC16F8X To convert code written for PIC16C5X to PIC16F8X, the user should take the following steps: 1. 2. 3. 4. 5. Remove any program memory page select operations (PA2, PA1, PA0 bits) for CALL, GOTO. Revisit any computed jump operations (write to PC or add to PC, etc.) to make sure page bits are set properly under the new scheme. Eliminate any data memory page switching. Redefine data variables for reallocation. Verify all writes to STATUS, OPTION, and FSR registers since these have changed. Change reset vector to 0000h. DS30430C-page 115 PIC16F8X APPENDIX C: WHAT'S NEW IN THIS DATA SHEET APPENDIX D: WHAT'S CHANGED IN THIS DATA SHEET Here's what's new in this data sheet: Here's what's changed in this data sheet: 1. 1. 2. 2. DC & AC Characteristics Graphs/Tables section for PIC16F8X devices has been added. An appendix on conversion considerations has been added. This explains differences for customers wanting to go from PIC16C84 to PIC16F84 or similar device. 3. 4. DS30430C-page 116 Errata information has been included. Option register name has been changed from OPTION to OPTION_REG. This is consistant with other data sheets and header files, and resolves the conflict between the OPTION command and OPTION register. Errors have been fixed. The appendix containing PIC16/17 microcontrollers has been removed. 1998 Microchip Technology Inc. PIC16F8X APPENDIX E: CONVERSION CONSIDERATIONS - PIC16C84 TO PIC16F83/F84 AND PIC16CR83/CR84 Considerations for converting from the PIC16C84 to the PIC16F84 are listed in the table below. These considerations apply to converting from the PIC16C84 to the PIC16F83 (same as PIC16F84 except for program Difference and data RAM memory sizes) and the PIC16CR84 and PIC16CR83 (ROM versions of Flash devices). Development Systems support is available for all of the PIC16X8X devices. PIC16C84 PIC16F84 The polarity of the PWRTE bit has been reversed. Ensure that the programmer has this bit correctly set before programming. PWRTE PWRTE The PIC16F84 (and PIC16CR84) have larger RAM sizes. Ensure that this does not cause an issue with your program. RAM = 36 bytes RAM = 68 bytes The MCLR pin now has an on-chip filter. The input signal on the MCLR pin will require a longer low pulse to generate an interrupt. MCLR pulse width (low) = 350ns; 2.0V VDD 3.0V = 150ns; 3.0V VDD 6.0V MCLR pulse width (low) = 1000ns; 2.0V VDD 6.0V Some electrical specifications have been improved (see IPD example). Compare the electrical specifications of the two devices to ensure that this will not cause a compatibility issue. IPD (typ @ 2V) = 26A IPD (typ @ 2V) < 1A IPD (max @ 4V, WDT disabled) =100A (PIC16C84) =100A (PIC16LC84) IPD (max @ 4V, WDT disabled) =14A (PIC16F84) =7A (PIC16LF84) PORTA and crystal oscillator values less than 500kHz For crystal oscillator configurations operating below 500kHz, the device may generate a spurious internal Q-clock when PORTA<0> switches state. N/A RB0/INT pin TTL TTL/ST* (* This buffer is a Schmitt Trigger input when configured as the external interrupt.) EEADR<7:6> and IDD It is recommended that the EEADR<7:6> bits be cleared. When either of these bits is set, the maximum IDD for the device is higher than when both are cleared. N/A Code Protect 1 CP bit 9 CP bits Recommended value of REXT for RC oscillator circuits REXT = 3k - 100k REXT = 5k - 100k GIE bit unintentional enable If an interrupt occurs while the Global Interrupt Enable (GIE) bit is being cleared, the GIE bit may unintentionally be re-enabled by the user's Interrupt Service Routine (the RETFIE instruction). N/A 1998 Microchip Technology Inc. DS30430C-page 117 PIC16F8X NOTES: DS30430C-page 118 1998 Microchip Technology Inc. PIC16F8X INDEX Numerics 8.1 Configuration Bits ......................................................... 37 A Absolute Maximum Ratings ......................................... 73, 85 ALU ...................................................................................... 7 Architectural Overview ......................................................... 7 Assembler MPASM Assembler .................................................... 70 B Block Diagram Interrupt Logic ............................................................ 47 On-Chip Reset Circuit ................................................ 41 RA3:RA0 and RA5 Port Pins ..................................... 21 RA4 Pin ...................................................................... 21 RB7:RB4 Port Pins .................................................... 23 TMR0/WDT Prescaler ................................................ 30 Watchdog Timer ......................................................... 50 Brown-out Protection Circuit .............................................. 46 C Carry .................................................................................... 7 CLKIN .................................................................................. 9 CLKOUT .............................................................................. 9 Code Protection ........................................................... 37, 52 Compatibility, upward ........................................................... 3 Computed GOTO ............................................................... 18 Configuration Bits ............................................................... 37 D DC Characteristics ................... 75, 76, 77, 78, 87, 88, 89, 90 Development Support ........................................................ 69 Development Tools ............................................................ 69 Digit Carry ............................................................................ 7 E CALL .......................................................................... 57 CLRF ......................................................................... 58 CLRW ........................................................................ 58 CLRWDT ................................................................... 58 COMF ........................................................................ 59 DECF ......................................................................... 59 DECFSZ .................................................................... 59 GOTO ........................................................................ 60 INCF .......................................................................... 60 INCFSZ ...................................................................... 61 IORLW ....................................................................... 61 IORWF ....................................................................... 62 MOVF ........................................................................ 62 MOVLW ..................................................................... 62 MOVWF ..................................................................... 62 NOP ........................................................................... 63 OPTION ..................................................................... 63 RETFIE ...................................................................... 63 RETLW ...................................................................... 64 RETURN .................................................................... 64 RLF ............................................................................ 65 RRF ........................................................................... 65 SLEEP ....................................................................... 66 SUBLW ...................................................................... 66 SUBWF ...................................................................... 67 SWAPF ...................................................................... 67 TRIS .......................................................................... 67 XORLW ..................................................................... 68 XORWF ..................................................................... 68 Section ....................................................................... 53 Summary Table ......................................................... 54 INT Interrupt ...................................................................... 48 INTCON ........................................................... 17, 42, 47, 48 INTEDG ............................................................................. 48 Interrupts Flag ............................................................................ 47 Interrupt on Change Feature ..................................... 23 Interrupts ............................................................. 37, 47 Electrical Characteristics .............................................. 73, 85 External Power-on Reset Circuit ........................................ 43 K F L Family of Devices PIC16C8X .................................................................... 3 FSR .............................................................................. 19, 42 Fuzzy Logic Dev. System (fuzzyTECH-MP) ................... 71 Loading of PC .................................................................... 18 G GIE ..................................................................................... 47 I I/O Ports ............................................................................. 21 I/O Programming Considerations ....................................... 25 ICEPIC Low-Cost PIC16CXXX In-Circuit Emulator ........... 69 In-Circuit Serial Programming ...................................... 37, 52 INDF ................................................................................... 42 Instruction Format .............................................................. 53 Instruction Set ADDLW ...................................................................... 55 ADDWF ...................................................................... 55 ANDLW ...................................................................... 55 ANDWF ...................................................................... 55 BCF ............................................................................ 56 BSF ............................................................................ 56 BTFSC ....................................................................... 56 BTFSS ....................................................................... 57 1998 Microchip Technology Inc. KeeLoq Evaluation and Programming Tools .................. 71 M MCLR ...................................................................... 9, 41, 42 Memory Organization Data Memory ............................................................. 12 Memory Organization ................................................ 11 Program Memory ....................................................... 11 MP-DriveWayTM - Application Code Generator ................. 71 MPLAB C ........................................................................... 71 MPLAB Integrated Development Environment Software ... 70 O OPCODE ........................................................................... 53 OPTION ................................................................. 16, 42, 48 OSC selection .................................................................... 37 OSC1 ................................................................................... 9 OSC2 ................................................................................... 9 Oscillator HS ........................................................................ 39, 46 LP ........................................................................ 39, 46 RC ....................................................................... 39, 40 XT .............................................................................. 39 Oscillator Configurations .................................................... 39 DS30430C-page 119 PIC16F8X P Paging, Program Memory .................................................. 18 PCL .............................................................................. 18, 42 PCLATH ....................................................................... 18, 42 PD .......................................................................... 15, 41, 46 PICDEM-1 Low-Cost PICmicro Demo Board ..................... 70 PICDEM-2 Low-Cost PIC16CXX Demo Board .................. 70 PICDEM-3 Low-Cost PIC16CXXX Demo Board ................ 70 PICMASTER In-Circuit Emulator ..................................... 69 PICSTART Plus Entry Level Development System ........ 69 Pinout Descriptions .............................................................. 9 POR ................................................................................... 43 Oscillator Start-up Timer (OST) ........................... 37, 43 Power-on Reset (POR) .................................. 37, 42, 43 Power-up Timer (PWRT) ..................................... 37, 43 Time-out Sequence .................................................... 46 Time-out Sequence on Power-up .............................. 44 TO .................................................................. 15, 41, 46 Port RB Interrupt ................................................................ 48 PORTA ..................................................................... 9, 21, 42 PORTB ..................................................................... 9, 23, 42 Power-down Mode (SLEEP) .............................................. 51 Prescaler ............................................................................ 29 PRO MATE II Universal Programmer .............................. 69 Product Identification System ........................................... 121 Programming Considerations .................................... 50 Time-out .................................................................... 42 X XT ...................................................................................... 46 Z Zero bit ................................................................................. 7 R RBIF bit ........................................................................ 23, 48 RC Oscillator ...................................................................... 46 Read-Modify-Write ............................................................. 25 Register File ....................................................................... 12 Reset ............................................................................ 37, 41 Reset on Brown-Out ........................................................... 46 S Saving W Register and STATUS in RAM .......................... 49 SEEVAL Evaluation and Programming System .............. 71 SLEEP .................................................................... 37, 41, 51 Software Simulator (MPLAB-SIM) ...................................... 71 Special Features of the CPU .............................................. 37 Special Function Registers ................................................ 12 Stack .................................................................................. 18 Overflows ................................................................... 18 Underflows ................................................................. 18 STATUS ................................................................... 7, 15, 42 T time-out .............................................................................. 42 Timer0 Switching Prescaler Assignment ................................ 31 T0IF ............................................................................ 48 Timer0 Module ........................................................... 27 TMR0 Interrupt ........................................................... 48 TMR0 with External Clock .......................................... 29 Timing Diagrams Time-out Sequence .................................................... 44 Timing Diagrams and Specifications ............................ 80, 92 TRISA ................................................................................. 21 TRISB ........................................................................... 23, 42 W W ........................................................................................ 42 Wake-up from SLEEP .................................................. 42, 51 Watchdog Timer (WDT) ................................... 37, 41, 42, 50 WDT ................................................................................... 42 Period ......................................................................... 50 DS30430C-page 120 1998 Microchip Technology Inc. PIC16F8X ON-LINE SUPPORT Microchip provides on-line support on the Microchip World Wide Web (WWW) site. The web site is used by Microchip as a means to make files and information easily available to customers. To view the site, the user must have access to the Internet and a web browser, such as Netscape or Microsoft Explorer. Files are also available for FTP download from our FTP site. Connecting to the Microchip Internet Web Site Systems Information and Upgrade Hot Line The Systems Information and Upgrade Line provides system users a listing of the latest versions of all of Microchip's development systems software products. Plus, this line provides information on how customers can receive any currently available upgrade kits.The Hot Line Numbers are: 1-800-755-2345 for U.S. and most of Canada, and 1-602-786-7302 for the rest of the world. 980106 The Microchip web site is available by using your favorite Internet browser to attach to: www.microchip.com The file transfer site is available by using an FTP service to connect to: ftp://ftp.futureone.com/pub/microchip The web site and file transfer site provide a variety of services. Users may download files for the latest Development Tools, Data Sheets, Application Notes, User's Guides, Articles and Sample Programs. A variety of Microchip specific business information is also available, including listings of Microchip sales offices, distributors and factory representatives. Other data available for consideration is: * Latest Microchip Press Releases * Technical Support Section with Frequently Asked Questions * Design Tips * Device Errata * Job Postings * Microchip Consultant Program Member Listing * Links to other useful web sites related to Microchip Products * Conferences for products, Development Systems, technical information and more * Listing of seminars and events 1998 Microchip Technology Inc. Trademarks: The Microchip name, logo, PIC, PICSTART, PICMASTER and PRO MATE are registered trademarks of Microchip Technology Incorporated in the U.S.A. and other countries. PICmicro, FlexROM, MPLAB and fuzzyLAB are trademarks and SQTP is a service mark of Microchip in the U.S.A. fuzzyTECH is a registered trademark of Inform Software Corporation. IBM, IBM PC-AT are registered trademarks of International Business Machines Corp. Pentium is a trademark of Intel Corporation. Windows is a trademark and MS-DOS, Microsoft Windows are registered trademarks of Microsoft Corporation. CompuServe is a registered trademark of CompuServe Incorporated. All other trademarks mentioned herein are the property of their respective companies. DS30430C-page 121 PIC16F8X READER RESPONSE 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 (602) 786-7578. Please list the following information, and use this outline to provide us with your comments about this Data Sheet. To: Technical Publications Manager RE: Reader Response Total Pages Sent From: Name Company Address City / State / ZIP / Country Telephone: (_______) _________ - _________ FAX: (______) _________ - _________ Application (optional): Would you like a reply? Device: PIC16F8X Y N Literature Number: DS30430C Questions: 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 data sheet easy to follow? If not, why? 4. What additions to the data sheet do you think would enhance the structure and subject? 5. What deletions from the data sheet 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? 8. How would you improve our software, systems, and silicon products? DS30430C-page 122 1998 Microchip Technology Inc. PIC16F8X PIC16F8X 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. Device Device Frequency Range X -XX Frequency Temperature Range Range /XX XXX Package Pattern PIC16F8X(2), PIC16F8XT(3) PIC16LF8X(2), PIC16LF8XT(3) PIC16F8XA(2), PIC16F8XAT(3) PIC16LF8XA(2), PIC16LF8XAT(3) PIC16CR8X(2), PIC16CR8XT(3) PIC16LCR8X(2), PIC16LCR8XT(3) 04 10 20 (1) = 4 MHz = 10 MHz = 20 MHz = 0C to = -40C to +70C +85C (Commercial) (Industrial) Temperature Range b I Package P SO SS Pattern 3-digit Pattern Code for QTP, ROM (blank otherwise) = PDIP = SOIC (Gull Wing, 300 mil body) = SSOP Examples: a) PIC16F84 -04/P 301 = Commercial temp., PDIP package, 4 MHz, normal VDD limits, QTP pattern #301. b) PIC16LF84 - 04I/SO = Industrial temp., SOIC package, 200 kHz, Extended VDD limits. c) PIC16CR84 - 10I/P = ROM program memory, Industrial temp., PDIP package, 10MHz, normal VDD limits. Note 1: b = blank 2: F = Standard VDD range LF = Extended VDD range CR = ROM Version, Standard VDD range LCR = ROM Version, Extended VDD range 3: T = in tape and reel - SOIC, SSOP packages only. SALES AND SUPPORT Products supported by a preliminary Data Sheet may possibly have an errata sheet describing minor operational differences and recommended workarounds. To determine if an errata sheet exists for a particular device, please contact one of the following: 1. Your local Microchip sales office. 2. The Microchip Corporate Literature Center U.S. FAX: (602) 786-7277 3. The Microchip's Bulletin Board, via your local CompuServe number (CompuServe membership NOT required). Please specify which device, revision of silicon and Data Sheet (include Literature #) you are using. For latest version information and upgrade kits for Microchip Development Tools, please call 1-800-755-2345 or 1-602-786-7302. 1998 Microchip Technology Inc. DS30430C-page 123 Note the following details of the code protection feature on PICmicro(R) MCUs. * * * * * * The PICmicro family meets the specifications contained in the Microchip Data Sheet. Microchip believes that its family of PICmicro microcontrollers is one of the most secure products 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 PICmicro microcontroller in a manner outside the operating specifications contained in the data sheet. The person doing so may be 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 product. If you have any further questions about this matter, please contact the local sales office nearest to you. Information contained in this publication regarding device applications and the like is intended through suggestion only and may be superseded by updates. It is your responsibility to ensure that your application meets with your specifications. No representation or warranty is given and no liability is assumed by Microchip Technology Incorporated with respect to the accuracy or use of such information, or infringement of patents or other intellectual property rights arising from such use or otherwise. Use of Microchip's products as critical components in life support systems is not authorized except with express written approval by Microchip. No licenses are conveyed, implicitly or otherwise, under any intellectual property rights. Trademarks The Microchip name and logo, the Microchip logo, FilterLab, KEELOQ, microID, MPLAB, PIC, PICmicro, PICMASTER, PICSTART, PRO MATE, SEEVAL and The Embedded Control Solutions Company are registered trademarks of Microchip Technology Incorporated in the U.S.A. and other countries. dsPIC, ECONOMONITOR, FanSense, FlexROM, fuzzyLAB, In-Circuit Serial Programming, ICSP, ICEPIC, microPort, Migratable Memory, MPASM, MPLIB, MPLINK, MPSIM, MXDEV, PICC, PICDEM, PICDEM.net, rfPIC, Select Mode and Total Endurance are trademarks of Microchip Technology Incorporated in the U.S.A. Serialized Quick Turn Programming (SQTP) is a service mark of Microchip Technology Incorporated in the U.S.A. All other trademarks mentioned herein are property of their respective companies. (c) 2002, Microchip Technology Incorporated, Printed in the U.S.A., All Rights Reserved. Printed on recycled paper. Microchip received QS-9000 quality system certification for its worldwide headquarters, design and wafer fabrication facilities in Chandler and Tempe, Arizona in July 1999. The Company's quality system processes and procedures are QS-9000 compliant for its PICmicro(R) 8-bit MCUs, KEELOQ(R) code hopping devices, Serial EEPROMs and microperipheral products. In addition, Microchip's quality system for the design and manufacture of development systems is ISO 9001 certified. 2002 Microchip Technology Inc. M WORLDWIDE SALES AND SERVICE AMERICAS ASIA/PACIFIC Japan Corporate Office Australia 2355 West Chandler Blvd. Chandler, AZ 85224-6199 Tel: 480-792-7200 Fax: 480-792-7277 Technical Support: 480-792-7627 Web Address: http://www.microchip.com Microchip Technology Australia Pty Ltd Suite 22, 41 Rawson Street Epping 2121, NSW Australia Tel: 61-2-9868-6733 Fax: 61-2-9868-6755 Microchip Technology Japan K.K. Benex S-1 6F 3-18-20, Shinyokohama Kohoku-Ku, Yokohama-shi Kanagawa, 222-0033, Japan Tel: 81-45-471- 6166 Fax: 81-45-471-6122 Rocky Mountain China - Beijing 2355 West Chandler Blvd. Chandler, AZ 85224-6199 Tel: 480-792-7966 Fax: 480-792-7456 Microchip Technology Consulting (Shanghai) Co., Ltd., Beijing Liaison Office Unit 915 Bei Hai Wan Tai Bldg. No. 6 Chaoyangmen Beidajie Beijing, 100027, No. China Tel: 86-10-85282100 Fax: 86-10-85282104 Atlanta 500 Sugar Mill Road, Suite 200B Atlanta, GA 30350 Tel: 770-640-0034 Fax: 770-640-0307 Boston 2 Lan Drive, Suite 120 Westford, MA 01886 Tel: 978-692-3848 Fax: 978-692-3821 Chicago 333 Pierce Road, Suite 180 Itasca, IL 60143 Tel: 630-285-0071 Fax: 630-285-0075 Dallas 4570 Westgrove Drive, Suite 160 Addison, TX 75001 Tel: 972-818-7423 Fax: 972-818-2924 Detroit Tri-Atria Office Building 32255 Northwestern Highway, Suite 190 Farmington Hills, MI 48334 Tel: 248-538-2250 Fax: 248-538-2260 Kokomo 2767 S. Albright Road Kokomo, Indiana 46902 Tel: 765-864-8360 Fax: 765-864-8387 Los Angeles 18201 Von Karman, Suite 1090 Irvine, CA 92612 Tel: 949-263-1888 Fax: 949-263-1338 China - Chengdu Microchip Technology Consulting (Shanghai) Co., Ltd., Chengdu Liaison Office Rm. 2401, 24th Floor, Ming Xing Financial Tower No. 88 TIDU Street Chengdu 610016, China Tel: 86-28-6766200 Fax: 86-28-6766599 China - Fuzhou Microchip Technology Consulting (Shanghai) Co., Ltd., Fuzhou Liaison Office Unit 28F, World Trade Plaza No. 71 Wusi Road Fuzhou 350001, China Tel: 86-591-7503506 Fax: 86-591-7503521 China - Shanghai Microchip Technology Consulting (Shanghai) Co., Ltd. Room 701, Bldg. B Far East International Plaza No. 317 Xian Xia Road Shanghai, 200051 Tel: 86-21-6275-5700 Fax: 86-21-6275-5060 China - Shenzhen 150 Motor Parkway, Suite 202 Hauppauge, NY 11788 Tel: 631-273-5305 Fax: 631-273-5335 Microchip Technology Consulting (Shanghai) Co., Ltd., Shenzhen Liaison Office Rm. 1315, 13/F, Shenzhen Kerry Centre, Renminnan Lu Shenzhen 518001, China Tel: 86-755-2350361 Fax: 86-755-2366086 San Jose Hong Kong Microchip Technology Inc. 2107 North First Street, Suite 590 San Jose, CA 95131 Tel: 408-436-7950 Fax: 408-436-7955 Microchip Technology Hongkong Ltd. Unit 901-6, Tower 2, Metroplaza 223 Hing Fong Road Kwai Fong, N.T., Hong Kong Tel: 852-2401-1200 Fax: 852-2401-3431 New York Toronto 6285 Northam Drive, Suite 108 Mississauga, Ontario L4V 1X5, Canada Tel: 905-673-0699 Fax: 905-673-6509 India Microchip Technology Inc. India Liaison Office Divyasree Chambers 1 Floor, Wing A (A3/A4) No. 11, O'Shaugnessey Road Bangalore, 560 025, India Tel: 91-80-2290061 Fax: 91-80-2290062 Korea Microchip Technology Korea 168-1, Youngbo Bldg. 3 Floor Samsung-Dong, Kangnam-Ku Seoul, Korea 135-882 Tel: 82-2-554-7200 Fax: 82-2-558-5934 Singapore Microchip Technology Singapore Pte Ltd. 200 Middle Road #07-02 Prime Centre Singapore, 188980 Tel: 65-334-8870 Fax: 65-334-8850 Taiwan Microchip Technology Taiwan 11F-3, No. 207 Tung Hua North Road Taipei, 105, Taiwan Tel: 886-2-2717-7175 Fax: 886-2-2545-0139 EUROPE Denmark Microchip Technology Nordic ApS Regus Business Centre Lautrup hoj 1-3 Ballerup DK-2750 Denmark Tel: 45 4420 9895 Fax: 45 4420 9910 France Microchip Technology SARL Parc d'Activite du Moulin de Massy 43 Rue du Saule Trapu Batiment A - ler Etage 91300 Massy, France Tel: 33-1-69-53-63-20 Fax: 33-1-69-30-90-79 Germany Microchip Technology GmbH Gustav-Heinemann Ring 125 D-81739 Munich, Germany Tel: 49-89-627-144 0 Fax: 49-89-627-144-44 Italy Microchip Technology SRL Centro Direzionale Colleoni Palazzo Taurus 1 V. Le Colleoni 1 20041 Agrate Brianza Milan, Italy Tel: 39-039-65791-1 Fax: 39-039-6899883 United Kingdom Arizona Microchip Technology Ltd. 505 Eskdale Road Winnersh Triangle Wokingham Berkshire, England RG41 5TU Tel: 44 118 921 5869 Fax: 44-118 921-5820 01/18/02 2002 Microchip Technology Inc.