DS2143/DS2143Q E1 Controller www.dalsemi.com FEATURES PIN ASSIGNMENT E1/ISDN-PRI framing transceiver Frames to CAS, CCS, and CRC4 formats Parallel control port Onboard two frame elastic store slip buffer Extracts and inserts CAS signaling bits Programmable output clocks for fractional E1 links, DS0 loopbacks, and drop and insert applications Onboard Sa data link support circuitry FEBE E-Bit detection, counting and generation Pin-compatible with DS2141A T1 Controller 5V supply; low power (50 mW) CMOS Available in 40-pin DIP and 44-pin PLCC (DS2143Q) TCLK TSER TCHCLK TPOS TNEG AD0 AD1 AD2 AD3 AD4 AD5 AD6 1 2 3 4 5 6 7 8 9 10 11 12 40 39 38 37 36 35 34 33 32 31 30 29 VDD TSYNC AD7 13 28 SYSCLK BTS RD(DS) CS ALE(AS) WR(R/W) 14 27 15 16 17 18 26 25 24 23 RNEG RPOS RSYNC RSER RLINK 19 22 RCLK VSS 20 21 RLCLK TLINK TLCLK INT1 INT2 RLOS/LOTC TCHBLK RCHBLK LI_CS LI_CLK LI_SDI RCHCLK TNEG TPOS TCHCLK TSER TCLK VDD TSYNC TLINK TLCLK INT1 INT2 40-Pin DIP (600-mil) 7 41 40 39 8 6 5 4 3 2 1 44 43 42 38 9 37 10 36 11 35 44-PIN PLCC 12 34 13 33 14 32 15 31 16 30 17 18 19 20 21 22 23 24 25 26 27 29 28 RLOS/LOTC TCHBLK RCHBLK LI_CS LI_CLK LI_SDI NC NC SYSCLK RNEG RPOS NC CS ALE(AS) WR(R/W) RLINK VSS RLCLK RCLK RCHCLK RSER RSYNC AD0 AD1 AD2 AD3 AD4 AD5 AD6 AD7 BTS RD(DS) NC DESCRIPTION The DS2143 is a comprehensive, software-driven E1 framer. It is meant to act as a slave or coprocessor to a microcontroller or microprocessor. Quick access via the parallel control port allows a single micro to handle many E1 lines. The DS2143 is very flexible and can be configured into numerous orientations via software. The software orientation of the device allows the user to modify their design to conform to future E1 specification changes. The controller contains a set of 69 8-bit internal registers which the user 1 of 44 112099 DS2143/DS2143Q can access. These internal registers are used to configure the device and obtain information from the E1 link. The device fully meets al l of the latest E1 specifications, including CCITT G.704, G.706, and G.732. 1.0 INTRODUCTION The DS2143 E1 Controller has four main sections: the receive side, the transmit side, the line interface controller, and the parallel control port. See the Block Diagram. On the receive side, the device will clock in the serial E1 stream via the RPOS and RNEG pins. The synchronizer will locate the frame and multiframe patterns and establish their respective positions. This information will be used by the rest of the receive side circuitry. The DS2143 is an "off-line" framer, which means that all of the E1 serial stream that goes into the device will come out of it unchanged. Once the E1 data has been framed to, the signaling data can be extracted. The two-frame elastic store can either be enabled or bypassed. The transmit side clocks in the unframed E1 stream at TSER and add in the framing pattern and the signaling. The line interface control port will update line interface devices that contain a serial port. The parallel control port contains a multiplexed address and data structure which can be connected to either a microcontroller or microprocessor. Reader's Note: This data sheet assumes a particular nomenclature of the E1 operating environment. There are 32 8-bit timeslots in an E1 systems which are number 0 to 31. Timeslot 0 is transmitted first and received first. These 32 timeslots are also referred to as channels with a numbering scheme of 1 to 32. Timeslot 0 is identical to channel 1, timeslot 1 is identical to channel 2, and so on. Each timeslot (or channel) is made up of 8 bits which are numbered 1 to 8. Bit number 1 is the MSB and is transmitted first. Bit number 8 is the LSB and is transmitted last. Throughout this data sheet, the following abbreviations will be used: FAS CRC4 CAS CCS MF Sa Si E-bit Frame Alignment Signal Cyclical Redundancy Check Channel Associated Signaling Common Channel Signaling Multiframe Additional bits International bits CRC4 Error Bits 2 of 44 DS2143/DS2143Q DS2143 FEATURES Parallel control port Onboard two-frame elastic store CAS signaling bit extraction and insertion Fully independent transmit and receive sections Full alarm detection Full access to Si and Sa bits Loss of transmit clock detection HDB3 coder/decoder Full transmit transparency Large error counters Individual bit-by-bit Sa data link support circuitry Programmable output clocks Frame sync generation Local loopback capability Automatic CRC4 E-bit support Loss of receive clock detection G.802 E1 to T1 mapping support DS2143 BLOCK DIAGRAM 3 of 44 DS2143/DS2143Q PIN DESCRIPTION Table 1 PIN 1 SYMBOL TCLK 2 TSER 3 TCHCLK 4 5 6-13 14 TPOS TNEG AD0-AD7 BTS 15 16 17 RD (DS) CS ALE(AS) 18 19 WR (R/ W ) 20 21 VSS RLCLK 22 RCLK 23 RCHCLK 24 RSER 25 RSYNC 26 27 RPOS RNEG 28 SYSCLK RLINK TYPE DESCRIPTION I Transmit Clock. 2.048 MHz primary clock. A clock must be applied at the TCLK pin for the parallel port to operate properly. I Transmit Serial Data. Transmit NRZ serial data, sampled on the falling edge of TCLK. O Transmit Channel Clock. 256 kHz clock which pulses high during the LSB of each channel. Useful for parallel-to-serial conversion of channel data. See Section 13 for timing details. O Transmit Bipolar Data. Updated on rising edge of TCLK. For optical links, can be programmed to output NRZ data. I/O Address/Data Bus. An 8-bit multiplexed address/data bus. I Bus Type Select. Strap high to select Motorola bus timing; strap low to select Intel bus timing. This pin controls the function of RD (DS), ALE(AS), and WR (R/ W ) pins. If BTS=1, then these pins assume the function listed in parentheses (). I Read Input (Data Strobe). I Chip Select. Must be low to read or write the port. I Address Latch Enable (Address Strobe). A positive-going edge serves to demultiplex the bus. I Write Input (Read/Write). O Receive Link Data. Outputs Sa bits. See Section 13 for timing details. Signal Ground. 0.0 volts. O Receive Link Clock. 4 kHz to 20 kHz demand clock for the RLINK output. Controlled by RCR2. See Section 13 for timing details. I Receive Clock. 2.048 MHz primary clock. A clock must be applied at the RCLK pin for the parallel port to operate properly. O Receive Channel Clock. 256 kHz clock which pulses high during the LSB of each channel. Useful for serial to parallel conversion of channel data. See Section 13 for timing details. O Receive Serial Data. Received NRZ serial data, updated on rising edges of RCLK. I/O Receive Sync. An extracted pulse, one RCLK wide, is output at this pin which identifies either frame (RCR1.6=0) or multiframe boundaries (RCR1.6=1). If the elastic store is enabled via the RCR2.1, then this pin can be enabled to be an input via RCR1.5 at which a frame boundary pulse is applied. See Section 13 for timing details. I Receive Bipolar Data Inputs. Sampled on falling edge of RCLK. Tie together to receive NRZ data and disable BPV monitoring circuitry. I System Clock. 1.544 MHz or 2.048 MHz clock. Only used when the elastic store function is enabled via the RCR2.1. Should be tied low in applications that do not use the elastic store. 4 of 44 DS2143/DS2143Q PIN 29 SYMBOL LI_SDI 30 LI_CLK 31 LI_ CS 32 33 RCHBLK TCHBLK 34 RLOS/LOTC 35 INT2 36 INT1 37 TLCLK 38 TLINK 39 TSYNC 40 VDD TYPE DESCRIPTION O Serial Port Data for the Line Interface. Connects directly to the SDI input pin on the line interface. See Sections 12 and 13 for timing details. O Serial Port Clock for the Line Interface. Connects directly to the SCLK input pin on the line interface. See Sections 12 and 13 for timing details. O Serial Port Chip Select for the Line Interface. Connects directly to the CS input pin on the line interface. See Sections 12 and 13 for timing details. O Receive/Transmit Channel Block. A user programmable output that can be forced high or low during any of the 32 E1 channels. Useful for blocking clocks to a serial UART or LAPD controller in applications where not all E1 channels are used such as Fractional E1 or ISDN-PRI. Also useful for locating individual channels in drop-and-insert applications. See Sections 9 and 13 for details. O Receive Loss of Sync/Loss of Transmit Clock. A dual function output. If TCR2.0=0, then this pin will toggle high when the synchronizer is searching for the E1 frame and multiframe. If TCR2.0=1, then this pin will toggle high if the TCLK pin has not toggled for 5 s. O Receive Alarm Interrupt 2. Flags host controller during conditions defined in Status Register 2. Active low, open drain output. O Receive Alarm Interrupt 1. Flags host controller during alarm conditions defined in Status Register 1. Active low, open drain output. O Transmit Link Clock. 4 kHz to 20 kHz demand clock for the TLINK input. Controlled by TCR2. See Section 13 for timing details. I Transmit Link Data. If enabled, this pin will be sampled on the falling edge of TCLK to insert Sa bits. See Section 13 for timing details. I/O Transmit Sync. A pulse at this pin will establish either frame or CAS multiframe boundaries for the DS2143. Via TCR1.1, the DS2143 can be programmed to output either a frame or multiframe pulse at this pin. See Section 13 for timing details. Positive Supply. 5.0 volts. 5 of 44 DS2143/DS2143Q DS2143 REGISTER MAP ADDRESS A7 to A0 00000000 HEX 00000001 01 00 00000010 02 00000011 03 00000100 04 00000101 05 00000110 06 00000111 07 00001000 08 00011110 1E 00010110 16 00010111 00010000 00010001 00010010 17 10 11 12 00010011 13 00010100 14 00010101 00011000 15 18 00011001 19 00100000 20 R/W REGISTER NAME R Bipolar Violation Count Register 1. R Bipolar Violation Count Register 2. R CRC4 Count Register 1. R CRC4 Count Register 2. R E-Bit Count Register 1. R E-Bit Count Register 2. R/W Status Register 1. R/W Status Register 2. R/W Receive Information Register. R Synchronizer Status Register. R/W Interrupt Mask Register 1. R/W Interrupt Mask Register 2. R/W Receive Control Register 1. R/W Receive Control Register 2. R/W Transmit Control Register 1. R/W Transmit Control Register 2. R/W Common Control Register. R/W Test Register. W LI Control Register Byte 1. W LI Control Register Byte 2. R/W Transmit Align Frame Register. 6 of 44 ADDRESS A7 to A0 00100001 HEX R/W 21 R/W 00101111 2F R 00011111 1F R 00100010 22 R/W 00100011 23 R/W 00100100 24 R/W 00100101 25 R/W 00100110 26 R/W 00100111 27 R/W 00101000 28 R/W 00101001 29 R/W 00101010 2A R/W 00101011 2B R/W 00101100 2C R/W 00101101 2D R/W REGISTER NAME Transmit NonAlign Frame Register. Receive Align Frame Register. Receive NonAlign Frame Register. Transmit Channel Blocking Register 1. Transmit Channel Blocking Register 2. Transmit Channel Blocking Register 3. Transmit Channel Blocking Register 4. Transmit Idle Register 1. Transmit Idle Register 2. Transmit Idle Register 3. Transmit Idle Register 4. Transmit Idle Definition Register. Receive Channel Blocking Register 1. Receive Channel Blocking Register 2. Receive Channel Blocking Register 3. DS2143/DS2143Q ADDRESS A7 to A0 00101110 HEX R/W 2E R/W 00110000 30 R 00110001 31 R 00110010 32 R 00110011 33 R 00110100 34 R 00110101 35 R 00110110 36 R 00110111 37 R 00111000 38 R 00111001 39 R 00111010 3A R 00111011 3B R 00111100 3C R 00111101 3D R REGISTER NAME Receive Channel Blocking Register 4. Receive Signaling Register 1. Receive Signaling Register 2. Receive Signaling Register 3. Receive Signaling Register 4. Receive Signaling Register 5. Receive Signaling Register 6. Receive Signaling Register 7. Receive Signaling Register 8. Receive Signaling Register 9. Receive Signaling Register 10. Receive Signaling Register 11. Receive Signaling Register 12. Receive Signaling Register 13. Receive Signaling Register 14. 7 of 44 ADDRESS A7 to A0 00111110 HEX R/W 3E R 00111111 3F R 01000000 40 R/W 01000001 41 R/W 01000010 42 R/W 01000011 43 R/W 01000100 44 R/W 01000101 45 R/W 01000110 46 R/W 01000111 47 R/W 01001000 48 R/W 01001001 49 R/W 01001010 4A R/W 01001011 4B R/W 01001100 4C R/W REGISTER NAME Receive Signaling Register 15. Receive Signaling Register 16. Transmit Signaling Register 1. Transmit Signaling Register 2. Transmit Signaling Register 3. Transmit Signaling Register 4. Transmit Signaling Register 5. Transmit Signaling Register 6. Transmit Signaling Register 7. Transmit Signaling Register 8. Transmit Signaling Register 9. Transmit Signaling Register 10. Transmit Signaling Register 11. Transmit Signaling Register 12. Transmit Signaling Register 13. DS2143/DS2143Q ADDRESS A7 to A0 01001101 HEX R/W 4D R/W 01001110 4E R/W 01001111 4F R/W Note: All values indicated column are hexadecimal. REGISTER NAME Transmit Signaling Register 14. Transmit Signaling Register 15. Transmit Signaling Register 16. within the Address 2.0 PARALLEL PORT The DS2143 is controlled via a multiplexed bidirectional address/data bus by an external microcontroller or microprocessor. The DS2143 can operate with either Intel or Motorola bus timing configurations. If the BTS pin is tied low, Intel timing will be selected; if tied high, Motorola timing will be selected. All Motorola bus signals are listed in parentheses (). See the timing diagrams in the AC Electrical Characteristics for more details. The multiplexed bus on the DS2143 saves pins because the address information and data information share the same signal paths. The addresses are presented to the pins in the first portion of the bus cycle and data will be transferred on the pins during second portion of the bus cycle. Addresses must be valid prior to the falling edge of ALE(AS), at which time the DS2143 latches the address from the AD0 to AD7 pins. Valid write data must be present and held stable during the later portion of the DS or WR pulses. In a read cycle, the DS2143 outputs a byte of data during the latter portion of the DS or RD pulses. The read cycle is terminated and the bus returns to a high impedance state as RD transitions high in Intel timing or as DS transitions low in Motorola timing. 3.0 CONTROL AND TEST REGISTERS The operation of the DS2143 is configured via a set of five registers. Typically, the control registers are only accessed when the system is first powered up. Once the DS2143 has been initialized, the control registers will only need to be accessed when there is a change in the system configuration. There are two Receive Control Registers (RCR1 and RCR2), two Transmit Control Registers (TCR1 and TCR2), and a Common Control Register (CCR). Each of the five registers is described in this section. The Test Register at address 15 hex is used by the factory in testing the DS2143. On power-up, the Test Register should be set to 00 hex in order for the DS2143 to operate properly. 8 of 44 DS2143/DS2143Q RCR1: RECEIVE CONTROL REGISTER 1 (Address=10 Hex) (MSB) RSMF RSM RSIO - - FRC SYNCE (LSB) RESYNC SYMBOL POSITION NAME AND DESCRIPTION RSMF RCR1.7 RSYNC Multiframe Function. Only used if the RSYNC pin is programmed in the multiframe mode (RCR1.6=1). 0 = RSYNC outputs CAS multiframe boundaries 1 = RSYNC outputs CRC4 multiframe boundaries RSM RCR1.6 RSYNC Mode Select. 0 = frame mode (see the timing in Section 13) 1 = multiframe mode (see the timing in Section 13) RSIO RCR1.5 RSYNC I/O Select. 0 = RSYNC is an output (depends on RCR1.6) 1 = RSYNC is an input (only valid if elastic store enabled) (note: this bit must be set to 0 when RCR2.1=0) - RCR1.4 Not Assigned. Should be set to 0 when written to. - RCR1.3 Not Assigned. Should be set to 0 when written to. FRC RCR1.2 Frame Resync Criteria. 0 = resync if FAS received in error 3 consecutive times 1 = resync if FAS or bit 2 of non-FAS is received in error 3 consecutive times SYNCE RCR1.1 Sync Enable. 0 = auto resync enabled 1 = auto resync disabled RESYNC RCR1.0 Resync. When toggled from low to high, a resync is initiated. Must be cleared and set again for a subsequent resync. 9 of 44 DS2143/DS2143Q SYNC/RESYNC CRITERIA Table 2 FRAME OR MULTIFRAME LEVEL FAS SYNC CRITERIA RESYNC CRITERIA FAS present in frames N and N + 2, and FAS not present in frame N + 1. CRC4 Two valid MF alignment words found within 8 ms. CAS Valid MF alignment word found and previous time slot 16 contains code other than all 0s. Three consecutive incorrect FAS received. Alternate (RCR1.2=1) the above criteria is met or three consecutive incorrect bit 2 of non-FAS received. 915 or more CRC4 code words out of 1000 received in error. Two consecutive MF alignment words received in error. ITU SPEC. G.706 4.1.1 4.1.2 G.706 4.2 4.3.2 G.732 5.2 RCR2: RECEIVE CONTROL REGISTER 2 (Address=11 Hex) (MSB) Sa8S Sa7S Sa6S Sa5S Sa4S SCLKM ESE (LSB) - SYMBOL POSITION NAME AND DESCRIPTION Sa8S RCR2.7 Sa8 Bit Select. Set to 1 to report the Sa8 bit at the RLINK pin; set to 0 to not report the Sa8 bit. Sa7S RCR2.6 Sa7 Bit Select. Set to 1 to report the Sa7 bit at the RLINK pin; set to 0 to not report the Sa7 bit. Sa6S RCR2.5 Sa6 Bit Select. Set to 1 to report the Sa6 bit at the RLINK pin; set to 0 to not report the Sa6 bit. Sa5S RCR2.4 Sa5 Bit Select. Set to 1 to report the Sa5 bit at the RLINK pin; set to 0 to not report the Sa5 bit. Sa4S RCR2.3 Sa4 Bit Select. Set to 1 to report the Sa4 bit at the RLINK pin; set to 0 to not report the Sa4 bit. SCLKM RCR2.2 SYSCLK Mode Select. 0 = if SYSCLK is 1.544 MHz. 1 = if SYSCLK is 2.048 MHz. ESE RCR2.1 Elastic Store Enable. 0 = elastic store is bypassed. 1 = elastic store is enabled. - RCR2.0 Not Assigned. Should be set to 0 when written to. 10 of 44 DS2143/DS2143Q TCR1: TRANSMIT CONTROL REGISTER 1 (Address=12 Hex) (MSB) ODF TFPT T16S TUA1 TSiS TSA1 TSM (LSB) TSIO SYMBOL POSITION NAME AND DESCRIPTION ODF TCR1.7 Output Data Format. 0 = bipolar data at TPOS and TNEG. 1 = NRZ data at TPOS; TNEG=0. TFPT TCR1.6 Transmit Timeslot 0 Pass Through. 0 = FAS bits/Sa bits/Remote Alarm sourced internally from the TAF and TNAF registers. 1 = FAS bits/Sa bits/Remote Alarm sourced from TSER. T16S TCR1.5 Transmit Timeslot 16 Data Select. 0 = sample timeslot 16 at TSER pin. 1 = source timeslot 16 from TS1 to TS16 registers. TUA1 TCR1.4 Transmit Unframed All 1s. 0 = transmit data normally. 1 = transmit an unframed all 1s code at TPOS and TNEG. TSiS TCR1.3 Transmit International Bit Select. 0 = sample Si bits at TSER pin. 1 = source Si bits from TAF and TNAF registers (in this mode, TCR1.6 must be set to 0). TSA1 TCR1.2 Transmit Signaling All 1s. 0 = normal operation. 1 = force timeslot 16 in every frame to all 1s. TSM TCR1.1 TSYNC Mode Select. 0 = frame mode (see the timing in Section 13). 1 = CAS and CRC4 multiframe mode (see the timing in Section 13). TSIO TCR1.0 TSYNC I/O Select. 0 = TSYNC is an input. 1 = TSYNC is an output. 11 of 44 DS2143/DS2143Q TCR2: TRANSMIT CONTROL REGISTER 2 (Address=13 Hex) (MSB) Sa8S Sa7S Sa6S Sa5S Sa4S - AEBE (LSB) P34F SYMBOL POSITION NAME AND DESCRIPTION Sa8S TCR2.7 Sa8 Bit Select. Set to 1 to source the Sa8 bit from the TLINK pin; set to 0 to not source the Sa8 bit. Sa7S TCR2.6 Sa7 Bit Select. Set to 1 to source the Sa7 bit from the TLINK pin; set to 0 to not source the Sa7 bit. Sa6S TCR2.5 Sa6 Bit Select. Set to 1 to source the Sa6 bit from the TLINK pin; set to 0 to not source the Sa6 bit. Sa5S TCR2.4 Sa5 Bit Select. Set to 1 to source the Sa5 bit from the TLINK pin; set to 0 to not source the Sa5 bit. Sa4S TCR2.3 Sa4 Bit Select. Set to 1 to source the Sa4 bit from the TLINK pin; set to 0 to not source the Sa4 bit. - TCR2.2 Not Assigned. Should be set to 0 when written to. AEBE TCR2.1 Automatic E-Bit Enable. 0 = E-bits not automatically set in the transmit direction. 1 = E-bits automatically set in the transmit direction. P34F TCR2.0 Function of Pin 34. 0 = Receive Loss of Sync (RLOS). 1 = Loss of Transmit Clock (LOTC). 12 of 44 DS2143/DS2143Q CCR: COMMON CONTROL REGISTER (Address=14 Hex) (MSB) LLB THDB3 TG802 TCRC4 RSM RHDB3 RG802 (LSB) RCRC4 SYMBOL POSITION NAME AND DESCRIPTION LLB CCR.7 Local Loopback. 0 = loopback disabled. 1 = loopback enabled. THDB3 CCR.6 Transmit HDB3 Enable. 0 = HDB3 disabled. 1 = HDB3 enabled. TG802 CCR.5 Transmit G.802 Enable. See Section 13 for details. 0 = do not force TCHBLK high during bit 1 of timeslot 26. 1 = force TCHBLK high during bit 1 of timeslot 26. TCRC4 CCR.4 Transmit CRC4 Enable. 0 = CRC4 disabled. 1 = CRC4 enabled. RSM CCR.3 Receive Signaling Mode Select. 0 = CAS signaling mode. 1 = CCS signaling mode. RHDB3 CCR.2 Receive HDB3 Enable. 0 = HDB3 disabled. 1 = HDB3 enabled. RG802 CCR.1 Receive G.802 Enable. See Section 13 for details. 0 = do not force RCHBLK high during bit 1 of timeslot 26 1 = force RCHBLK high during bit 1 of timeslot 26. RCRC4 CCR.0 Receive CRC4 Enable. 0 = CRC4 disabled. 1 = CRC4 enabled. LOCAL LOOPBACK When CCR.7 is set to a 1, the DS2143 will enter a Local LoopBack (LLB) mode. This loopback is useful in testing and debugging applications. In LLB, the DS2143 will loop data from the transmit side back to the receive side. This loopback is synonymous with replacing the RCLK input with the TCLK signal, and the RPOS/RNEG inputs with the TPOS/TNEG outputs. When LLB is enabled, the following will occur: 1. data at RPOS and RNEG will be ignored; 2. all receive side signals will take on timing synchronous with TCLK instead of RCLK; 3. all functions are available. 13 of 44 DS2143/DS2143Q 4.0 STATUS AND INFORMATION REGISTERS There is a set of four registers that contain information on the current real time status of the DS2143: Status Register 1 (SR1), Status Register 2 (SR2), Receive Information Register (RIR), and Synchronizer Status Register (SSR). When a particular event has occurred (or is occurring), the appropriate bit in one of these three registers will be set to a 1. All of the bits in these registers operate in a latched fashion (except for the SSR). This means that if an event occurs and a bit is set to a 1 in any of the registers, it will remain set until the user reads that bit. The bit will be cleared when it is read and it will not be set again until the event has occurred again or if the alarm(s) is still present. The user will always precede a read of the SR1, SR2, and RIR registers with a write. The byte written to the register will inform the DS2143 which bits the user wishes to read and have cleared. The user will write a byte to one of these three registers, with a 1 in the bit positions he or she wishes to read and a 0 in the bit positions he or she does not wish to obtain the latest information on. When a 1 is written to a bit location, the read register will be updated with current value and it will be cleared. When a 0 is written to a bit position, the read register will not be updated and the previous value will be held. A write to the status and information registers will be immediately followed by a read of the same register. The read result should be logically AND'ed with the mask byte that was just written and this value should be written back into the same register to insure that the bit does indeed clear. This second write is necessary because the alarms and events in the status registers occur asynchronously in respect to their access via the parallel port. This scheme allows an external microcontroller or microprocessor to individually poll certain bits without disturbing the other bits in the register. This operation is key in controlling the DS2143 with higher order software languages. The SSR register operates differently than the other three. It is a read only register and it reports the status of the synchronizer in real time. This register is not latched and it is not necessary to precede a read of this register with a write. The SR1 and SR2 registers have the unique ability to initiate a hardware interrupt via the INT1 and INT2 pins respectively. Each of the alarms and events in the SR1 and SR2 can be either masked or unmasked from the interrupt pins via the Interrupt Mask Register 1 (IMR1) and Interrupt Mask Register 2 (IMR2) respectively. 14 of 44 DS2143/DS2143Q RIR: RECEIVE INFORMATION REGISTER (Address=08 Hex) (MSB) - - - ESF ESE - FASRC (LSB) CASRC SYMBOL POSITION NAME AND DESCRIPTION - RIR.7 Not Assigned. Could be any value when read. - RIR.6 Not Assigned. Could be any value when read. - RIR.5 Not Assigned. Could be any value when read. ESF RIR.4 Elastic Store Full. Set when the elastic store buffer fills and a frame is deleted. ESE RIR.3 Elastic Store Empty. Set when the elastic store buffer empties and a frame is repeated. - RIR.2 Not Assigned. Could be any value when read. FASRC RIR.1 FAS Resync Criteria Met. Set when three consecutive FAS words are received in error. CASRC RIR.0 CAS Resync Criteria Met. Set when two consecutive CAS MF alignment words are received in error. 15 of 44 DS2143/DS2143Q SSR: SYNCHRONIZER STATUS REGISTER (Address=1E Hex) (MSB) CSC5 CSC4 CSC3 CSC2 CSC0 FASSA CASSA (LSB) CRC4SA SYMBOL POSITION NAME AND DESCRIPTION CSC5 SSR.7 CRC4 Sync Counter Bit 5. MSB of the 6-bit counter. CSC4 SSR.6 CRC4 Sync Counter Bit 4. CSC3 SSR.5 CRC4 Sync Counter Bit 3. CSC2 SSR.4 CRC4 Sync Counter Bit 2. CSC1 SSR.3 CRC4 Sync Counter Bit 0. LSB of the 6-bit counter. The next to LSB is not accessible. FASSA SSR.2 FAS Sync Active. Set while the synchronizer is searching for alignment at the FAS level. CASSA SSR.1 CAS MF Sync Active. Set while the synchronizer is searching for the CAS MF alignment word. CRC4SA SSR.0 CRC4 MF Sync Active. Set while the synchronizer is searching for the CRC4 MF alignment word. CRC4 SYNC COUNTER The CRC4 Sync Counter increments each time the 8ms CRC4 multiframe search times out. The counter is cleared when the DS2143 has successfully obtained synchronization at the CRC4 level. The counter can also be cleared by disabling the CRC4 mode (CCR.0=0). This counter is useful for determining the amount of time the DS2143 has been searching for synchronization at the CRC4 level. Annex B of CCITT G.706 suggests that if synchronization at the CRC4 level cannot be obtained within 400 ms, then the search should be abandoned and proper action taken. The CRC4 Sync Counter will rollover 16 of 44 DS2143/DS2143Q SR1: STATUS REGISTER 1 (Address=06 Hex) (MSB) RSA1 RDMA RSA0 SLIP RUA1 RRA RCL (LSB) RLOS SYMBOL POSITION NAME AND DESCRIPTION RSA1 SR1.7 Receive Signaling All 1s. Set when the contents of timeslot 16 contains less than 3 0s over 16 consecutive frames. This alarm is not disabled in the CCS signaling mode. RDMA SR1.6 Receive Distant MF Alarm. Set when bit 6 of timeslot 16 in frame 0 has been set for 2 consecutive multiframes. This alarm is not disabled in the CCS signaling mode. RSA0 SR1.5 Receive Signaling All 0s. Set when over a full MF, timeslot 16 contains all 0s. SLIP SR1.4 Elastic Store Slip Occurrence. Set when the elastic store has either repeated or deleted a frame of data. RUA1 SR1.3 Receive Unframed All 1s. Set when an unframed all 1s code is received at RPOS and RNEG. RRA SR1.2 Receive Remote Alarm. Set when a remote alarm is received at RPOS and RNEG. RCL SR1.1 Receive Carrier Loss. Set when 255 consecutive 0s have been detected at RPOS and RNEG. RLOS SR1.0 Receive Loss of Sync. Set when the device is not synchronized to the receive E1 stream. 17 of 44 DS2143/DS2143Q ALARM CRITERIA Table 2 ALARM SET CRITERIA CLEAR CRITERIA ITU SPEC. G.732 4.2 RSA1 (receive signaling all 1s) over 16 consecutive frames (one full MF) timeslot 16 contains less than 3 0s over 16 consecutive frames (one full MF) timeslot 16 contains three or more 0s RSA0 (receive signaling all 0s) over 16 consecutive frames (one full MF) timeslot 16 contains all 0s over 16 consecutive frames (one full MF) timeslot 16 contains at least a single 1 G.732 5.2 bit 6 in timeslot 16 of frame 0 set to 0 for two consecutive MFs O.162 2.1.5 less than three 0s in two frames (512 bits) more than two 0s in two frames (512 bits) O.162 1.6.1.2 bit 3 of non-align frame set to 1 for three consecutive occasions bit 3 of non-align frame set to 0 for three consecutive occasions O.162 2.1.4 255 consecutive 0s received in 255 bit times, at least 32 1s are received G.775 bit 6 in timeslot 16 of frame 0 RDMA (receive distant set to 1 for two consecutive multiframe alarm) MFs RUA1 (receive unframed all 1s) RRA (receive remote alarm) RCL (receive carrier loss) Note: all the alarm bits in Status Register 1 except the RUA1 will remain set after they are read if the alarm condition still exists; the RUA1 will clear and check the next 512 bits for an all 1s condition at which point it will again be set if the alarm condition still is present. 18 of 44 DS2143/DS2143Q SR2: STATUS REGISTER 2 (Address=07 Hex) (MSB) RMF RAF TMF SEC TAF LOTC RCMF (LSB) LORC SYMBOL POSITION NAME AND DESCRIPTION RMF SR2.7 Receive CAS Multiframe. Set every 2 ms (regardless if CAS signaling is enabled or not) on receive multiframe boundaries. Used to alert the host that signaling data is available. RAF SR2.6 Receive Align Frame. Set every 250 s at the beginning of align frames. Used to alert the host that Si and Sa bits are available in the RAF and RNAF registers. TMF SR2.5 Transmit Multiframe. Set every 2 ms (regardless if CRC4 is enabled) on transmit multiframe boundaries. Used to alert the host that signaling data needs to be updated. SEC SR2.4 One-Second Timer. Set on increments of 1 second based on RCLK. TAF SR2.3 Transmit Align Frame. Set every 250 s at the beginning of align frames. Used to alert the host that the TAF and TNAF registers need to be updated. LOTC SR2.2 Loss of Transmit Clock. Set when the TCLK pin has not transitioned for one channel time (or 3.9 s). Will force pin 34 high if enabled via TCR2.0. Based on RCLK. RCMF SR2.1 Receive CRC4 Multiframe. Set on CRC4 multiframe boundaries; will continue to be set every 2 ms on an arbitrary boundary if CRC4 is disabled. LORC SR2.0 Loss of Receive Clock. Set when the RCLK pin has not transitioned for at least 2 s (3 s 1 s). 19 of 44 DS2143/DS2143Q IMR1: INTERRUPT MASK REGISTER 1 (Address=16 Hex) (MSB) RSA1 RDMA RSA0 SLIP RUA1 RRA SYMBOL POSITION NAME AND DESCRIPTION RSA1 IMR1.7 Receive Signaling All 1s. 0 = interrupt masked. 1 = interrupt enabled. RDMA IMR1.6 Receive Distant MF Alarm. 0 = interrupt masked. 1 = interrupt enabled. RSA0 IMR1.5 Receive Signaling All 0s. 0 = interrupt masked. 1 = interrupt enabled. SLIP IMR1.4 Elastic Store Slip Occurrence. 0 = interrupt masked. 1 = interrupt enabled. RUA1 IMR1.3 Receive Unframed All 1s. 0 = interrupt masked. 1 = interrupt enabled. RRA IMR1.2 Receive Remote Alarm. 0 = interrupt masked. 1 = interrupt enabled. RCL IMR1.1 Receive Carrier Loss. 0 = interrupt masked. 1 = interrupt enabled. RLOS IMR1.0 Receive Loss of Sync. 0 = interrupt masked. 1 = interrupt enabled. 20 of 44 RCL (LSB) RLOS DS2143/DS2143Q IMR2: INTERRUPT MASK REGISTER 2 (Address=17 Hex) (MSB) RMF RAF TMF SEC TAF SYMBOL POSITION RMF IMR2.7 Receive CAS Multiframe. 0 = interrupt masked. 1 = interrupt enabled. RAF IMR2.6 Receive Align Frame. 0 = interrupt masked. 1 = interrupt enabled. TMF IMR2.5 Transmit Multiframe. 0 = interrupt masked. 1 = interrupt enabled. SEC IMR2.4 1-Second Timer. 0 = interrupt masked. 1 = interrupt enabled. TAF IMR2.3 Transmit Align Frame. 0 = interrupt masked. 1 = interrupt enabled. LOTC IMR2.2 Loss Of Transmit Clock. 0 = interrupt masked. 1 = interrupt enabled. RCMF IMR2.1 Receive CRC4 Multiframe. 0 = interrupt masked. 1 = interrupt enabled. LORC IMR2.0 Loss of Receive Clock. 0 = interrupt masked. 1 = interrupt enabled. LOTC RCMF (LSB) LORC NAME AND DESCRIPTION 5.0 ERROR COUNT REGISTERS There are a set of three counters in the DS2143 that record bipolar violations, errors in the CRC4 SMF code words, and E-bits as reported by the far end. Each of these three counters are automatically updated on 1-second boundaries as determined by the 1-second timer in Status Register 2 (SR2.4). Hence, these registers contain performance data from the previous second. The user can use the interrupt from the 1second timer to determine when to read these registers. The user has a full second to read the counters before the data is lost. 21 of 44 DS2143/DS2143Q BPVCR1: UPPER BIPOLAR VIOLATION COUNT REGISTER 1 (Address=00 Hex) BPVCR2: LOWER BIPOLAR VIOLATION COUNT REGISTER 2 (Address=01 Hex) (MSB) BV7 BV15 BV6 BV14 BV5 BV13 BV4 BV12 BV3 BV11 BV2 BV10 BV1 BV9 SYMBOL POSITION NAME AND DESCRIPTION BV15 BPVCR1.7 MSB of the bipolar violation count. BV0 BPVCR2.0 LSB of the bipolar violation count. (LSB) BV0 BPVCR2 BV8 BPVCR1 Bipolar Violation Count Register 1 (BPVCR1) is the most significant word and BPVCR2 is the least significant word of a 16-bit counter that records bipolar violations (BPVs). If the HDB3 mode is set for the receive side via CCR.2, then HDB3 code words are not counted. This counter increments at all times and is not disabled by loss of sync conditions. The counter saturates at 65,535 and will not rollover. The bit error rate on a E1 line would have to be greater than 10**-2 before the BPVCR would saturate. CRCCR1: CRC4 COUNT REGISTER 1 (Address=02 Hex) CRCCR2: CRC4 COUNT REGISTER 2 (Address=03 Hex) (MSB) CRC7 CRC14 CRC6 CRC14 CRC5 CRC13 CRC4 CRC12 CRC3 CRC11 CRC2 CRC10 SYMBOL POSITION NAME AND DESCRIPTION CRC15 CRCCR1.7 MSB of the CRC4 error count. CRC0 CRCCR2.0 LSB of the CRC4 error count. CRC1 CRC9 (LSB) CRC0 CRCCR2 CRC8 CRCCR1 CRC4 Count Register 1 (CRCCR1) is the most significant word and CRCCR2 is the least significant word of a 16-bit counter that records word errors in the Cyclic Redundancy Check 4 (CRC4). Since the maximum CRC4 count in a 1-second period is 1000, this counter cannot saturate. The counter is disabled during loss of sync at either the FAS or CRC4 level; it will continue to count if loss of sync occurs at the CAS level. 22 of 44 DS2143/DS2143Q EBCR1: E-BIT COUNT REGISTER 1 (Address=04 Hex) EBCR2: E-BIT COUNT REGISTER 2 (Address=05 Hex) (MSB) EB7 EB15 EB6 EB14 EB5 EB13 EB4 EB12 EB3 EB11 EB2 EB10 SYMBOL POSITION EB15 EBCR1.7 MSB of the E-Bit error count. EB0 EBCR2.0 LSB of the E-Bit error count. EB1 EB9 (LSB) EB0 EB8 EBCR2 EBCR1 NAME AND DESCRIPTION E-bit Count Register 1 (EBCR1) is the most significant word and EBCR2 is the least significant word of a 16-bit counter that records Far End Block Errors (FEBE) as reported in the first bit of frames 13 and 15 on E1 lines running with CRC4 multiframe. These count registers will increment once each time the received E-bit is set to 0. Since the maximum E-bit count in a 1-second period is 1000, this counter cannot saturate. The counter is disabled during loss of sync at either the FAS or CRC4 level; it will continue to count if loss of sync occurs at the CAS level. 6.0 Sa DATA LINK CONTROL AND OPERATION The DS2143 provides for access to the proposed E1 performance monitor data link in the Sa bit positions. The device allows access to the Sa bits either via a set of two internal registers (RNAF and TNAF) or via two external pins (RLINK and TLINK). On the receive side, the Sa bits are always reported in the internal RNAF register (see Section 11 for more details). All five Sa bits are always output at the RLINK pin. See Section 13 for detailed timing. Via RCR2, the user can control the RLCLK pin to pulse during any combination of Sa bits. This allows the user to create a clock that can be used to capture the needed Sa bits. On the transmit side, the individual Sa bits can be either sourced from the internal TNAF register (TCR1.6=0) or from the external TLINK pin. Via TCR2, the DS2143 can be programmed to source any combination of the additional bits from the TLINK pin. If the user wishes to pass the Sa bits through the DS2143 without them being altered, then the device should be set up to source all 5 Sa bits via the TLINK pin and the TLINK pin should be tied to the TSER pin. Please see the timing diagrams and the transmit data flow diagram in Section 13 for examples. 7.0 SIGNALING OPERATION The Channel Associated Signaling (CAS) bits embedded in the E1 stream can be extracted from the receive stream and inserted into the transmit stream by the DS2143. Each of the 30 channels has 4 signaling bits (A/B/C/D) associated with it. The numbers in parenthesis () are the channel associated with a particular signaling bit. The channel numbers have been assigned as described in the CCITT documents. For example, channel 1 is associated with timeslot 1 and channel 30 is associated with timeslot 31. There is a set of 16 registers for the receive side (RS1 to RS16) and 16 registers on the transmit side (TS1 to TS16). The signaling registers are detailed below. 23 of 44 DS2143/DS2143Q RS1 TO RS16: RECEIVE SIGNALING REGISTERS (Address=30 to 3F Hex) (MSB) 0 A(1) A(2) A(3) A(4) A(5) A(6) A(7) A(8) A(9) A(10) A(11) A(12) A(13) A(14) A(15) 0 B(1) B(2) B(3) B(4) B(5) B(6) B(7) B(8) B(9) B(10) B(11) B(12) B(13) B(14) B(15) 0 C(1) C(2) C(3) C(4) C(5) C(6) C(7) C(8) C(9) C(10) C(11) C(12) C(13) C(14) C(15) 0 D(1) D(2) D(3) D(4) D(5) D(6) D(7) D(8) D(9) D(10) D(11) D(12) D(13) D(14) D(15) X A(16) A(17) A(18) A(19) A(20) A(21) A(22) A(23) A(24) A(25) A(26) A(27) A(28) A(29) A(30) Y B(16) B(17) B(18) B(19) B(20) B(21) B(22) B(23) B(24) B(25) B(26) B(27) B(28) B(29) B(30) X C(16) C(17) C(18) C(19) C(20) C(21) C(22) C(23) C(24) C(25) C(26) C(27) C(28) C(29) C(30) (LSB) X D(16) D(17) D(18) D(19) D(20) D(21) D(22) D(23) D(24) D(25) D(26) D(27) D(28) D(29) D(30) SYMBOL POSITION X RS1.0/1/3 Y RS1.2 Remote Alarm Bit (integrated and reported in SR1.6). A(1) RS2.7 Signaling Bit A for Channel 1. D(30) RS16.0 Signaling Bit D for Channel 30. RS1 (30) RS2 (31) RS3 (32) RS4 (33) RS5 (34) RS6 (35) RS7 (36) RS8 (37) RS9 (38) RS10 (39) RS11 (3A) RS12 (3B) RS13 (3C) RS14 (3D) RS15 (3E) RS16 (3F) NAME AND DESCRIPTION Spare Bits. Each Receive Signaling Register (RS1 to RS16) reports the incoming signaling from two timeslots. The bits in the Receive Signaling Registers are updated on multiframe boundaries so the user can utilize the Receive Multiframe Interrupt in the Receive Status Register 2 (SR2.7) to know when to retrieve the signaling bits. The user has a full 2 ms to retrieve the signaling bits before the data is lost. The RS registers are updated under all conditions. Their validity should be qualified by checking for synchronization at the CAS level. In CCS signaling mode, RS1 to RS16 can also be used to extract signaling information. Via the SR2.7 bit, the user will be informed when the signaling registers have been loaded with data. The user has 2 ms to retrieve the data before it is lost. 24 of 44 DS2143/DS2143Q TS1 TO TS16: TRANSMIT SIGNALING REGISTERS (Address=40 to 4F Hex) (MSB) 0 A(1) A(2) A(3) A(4) A(5) A(6) A(7) A(8) A(9) A(10) A(11) A(12) A(13) A(14) A(15) 0 B(1) B(2) B(3) B(4) B(5) B(6) B(7) B(8) B(9) B(10) B(11) B(12) B(13) B(14) B(15) 0 C(1) C(2) C(3) C(4) C(5) C(6) C(7) C(8) C(9) C(10) C(11) C(12) C(13) C(14) C(15) 0 D(1) D(2) D(3) D(4) D(5) D(6) D(7) D(8) D(9) D(10) D(11) D(12) D(13) D(14) D(15) X A(16) A(17) A(18) A(19) A(20) A(21) A(22) A(23) A(24) A(25) A(26) A(27) A(28) A(29) A(30) Y B(16) B(17) B(18) B(19) B(20) B(21) B(22) B(23) B(24) B(25) B(26) B(27) B(28) B(29) B(30) SYMBOL POSITION X TS1.0/1/3 Y TS1.2 Remote Alarm Bit. A(1) TS2.7 Signaling Bit A for Channel 1. D(30) TS16.0 Signaling Bit D for Channel 30. X C(16) C(17) C(18) C(19) C(20) C(21) C(22) C(23) C(24) C(25) C(26) C(27) C(28) C(29) C(30) (LSB) X D(16) D(17) D(18) D(19) D(20) D(21) D(22) D(23) D(24) D(25) D(26) D(27) D(28) D(29) D(30) TS1 (40) TS2 (41) TS3(42) TS4 (43) TS5 (44) TS6 (45) TS7 (46) TS8 (47) TS9 (48) TS10 (49) TS11 (4A) TS12 (4B) TS13(4C) TS14 (4D) TS15 (4E) TS16 (4F) NAME AND DESCRIPTION Spare Bits. Each Transmit Signaling Register (TS1 to TS16) contains the CAS bits for two timeslots that will be inserted into the outgoing stream if enabled to do so via TCR1.5. On multiframe boundaries, the DS2143 will load the values present in the Transmit Signaling Register into an outgoing signaling shift register that is internal to the device. The user can utilize the Transmit Multiframe bit in Status Register 2 (SR2.5) to know when to update the signaling bits. The bit will be set every 2 ms and the user has 2 ms to update the TSRs before the old data will be retransmitted. The TS1 register is special because it contains the CAS multiframe alignment word in its upper nibble. The upper 4 bits must always be set to 0000 or else the terminal at the far end will lose multiframe synchronization. If the user wishes to transmit a multiframe alarm to the far end, then the TS1.2 bit should be set to a 1. If no alarm is to be transmitted, then the TS1.2 bit should be cleared. The three remaining bits in TS1 are the spare bits. If they are not used, they should be set to 1. In CCS signaling mode, TS1 to TS16 can also be used to insert signaling information. Via the SR2.5 bit, the user will be informed when the signaling registers need to be loaded with data. The user has 2 ms to load the data before the old data will be retransmitted. 8.0 TRANSMIT IDLE REGISTERS There is a set of five registers in the DS2143 that can be used to custom tailor the data that is to be transmitted onto the E1 line, on a channel by channel basis. Each of the 32 E1 channels can be forced to have a user defined idle code inserted into them. 25 of 44 DS2143/DS2143Q TIR1/TIR2/TIR3/TIR4: TRANSMIT IDLE REGISTERS (Address=26 to 29 Hex) (MSB) CH8 CH16 CH24 CH32 CH7 CH15 CH23 CH31 CH6 CH14 CH22 CH30 CH5 CH13 CH21 CH29 CH4 CH12 CH20 CH28 CH3 CH11 CH19 CH27 CH2 CH10 CH18 CH26 (LSB) CH1 CH9 CH17 CH25 SYMBOL POSITION CH32 TIR4.7 Transmit Idle Registers. 0 = do not insert the Idle Code into this channel. CH1 TIR1.0 1 = insert the Idle Code into this channel. TIR1 (26) TIR2 (27) TIR3 (28) TIR4 (29) NAME AND DESCRIPTION TIDR: TRANSMIT IDLE DEFINITION REGISTER (Address=2A Hex) (MSB) TIDR7 TIDR6 TIDR5 TIDR4 TIDR3 SYMBOL POSITION TIDR7 TIDR.7 MSB of the Idle Code. TIDR0 TIDR.0 LSB of the Idle Code. TIDR2 TIDR1 (LSB) TIDR0 NAME AND DESCRIPTION Each of the bit positions in the Transmit Idle Registers (TIR1/TIR2/TIR3/TIR4) represents a timeslot in the outgoing frame. When these bits are set to a 1, the corresponding channel will transmit the Idle Code contained in the Transmit Idle Definition Register (TIDR). In the TIDR, the MSB is transmitted first. 9.0 CLOCK BLOCKING REGISTERS The Receive Channel Blocking Registers (RCBR1/RCBR2/RCBR3/RCBR4) and the Transmit Channel Blocking Registers (TCBR1/TCBR2/TCBR3/TCBR4) control the RCHBLK and TCHBLK pins respectively. The RCHBLK and TCHCLK pins are user-programmable outputs that can be forced either high or low during individual channels. These outputs can be used to block clocks to a USART or LAPD controller in ISDN-PRI applications. When the appropriate bits are set to a 1, the RCHBLK and TCHCLK pins will be held high during the entire corresponding channel time. See the timing in Section 13 for an example. 26 of 44 DS2143/DS2143Q RCBR1/RCBR2/RCBR3/RCBR4: RECEIVE CHANNEL BLOCKING REGISTERS (Address=2B to 2E Hex) (MSB) CH8 CH16 CH24 CH32 CH7 CH15 CH23 CH31 CH6 CH14 CH22 CH30 CH5 CH13 CH21 CH29 CH4 CH12 CH20 CH28 CH3 CH11 CH19 CH27 CH2 CH10 CH18 CH26 (LSB) CH1 RCBR1 (2B) CH9 RCBR2 (2C) CH17 RCBR3 (2D) CH25 RCBR4 (2E) SYMBOL POSITION NAME AND DESCRIPTION CH32 RCBR4.7 Receive Channel Blocking Registers. 0 = force the RCHBLK pin to remain low during this channel time. CH1 RCBR1.0 1 = force the RCHBLK pin high during this channel time. TCBR1/TCBR2/TCBR3/TCBR4: TRANSMIT CHANNEL BLOCKING REGISTERS (Address=22 to 25 Hex) (MSB) CH8 CH16 CH24 CH32 CH7 CH15 CH23 CH31 CH6 CH14 CH22 CH30 CH5 CH13 CH21 CH29 CH4 CH12 CH20 CH28 CH3 CH11 CH19 CH27 CH2 CH10 CH18 CH26 (LSB) CH1 CH9 CH17 CH25 TCBR1 (22) TCBR2 (23) TCBR3 (24) TCBR4 (25) SYMBOL POSITION NAME AND DESCRIPTION CH32 TCBR4.7 Receive Channel Blocking Registers. 0 = force the TCHBLK pin to remain low during this channel time. CH1 TCBR1.0 1 = force the TCHBLK pin high during this channel time. 10.0 ELASTIC STORE OPERATION The DS2143 has an onboard two-frame (512 bits) elastic store. This elastic store can be enabled via RCR2.1. If the elastic store is enabled (RCR2.1=1), then the user must provide either a 1.544 MHz (RCR2.2=0) or 2.048 MHz (RCR2.2=1) clock at the SYSCLK pin. If the elastic store is enabled, then the user has the option of either providing a frame sync at the RFSYNC pin (RCR1.5=1) or having the RFSYNC pin provide a pulse on frame or multiframe boundaries (RCR1.5=0). If the user wishes to obtain pulses at the frame boundary, then RCR1.6 must be set to 0, and if the user wishes to have pulses occur at the multiframe boundary, then RCR1.6 must be set to 1. If the user selects to apply a 1.544 MHz clock to the SYSCLK pin, then every fourth channel will be deleted and the F-bit position inserted (forced to 1). Hence channels 1, 5, 9, 13, 17, 21, 25, and 29 (timeslots 0, 4, 8, 12, 16, 20, 24, and 28) will be deleted. Also, in 1.544 MHz applications, the RCHBLK output will not be active in channels 25 through 32 (or in other words, RCBR4 is not active). See Section 13 for more details. If the 512-bit elastic buffer either fills or empties, a controlled slip will occur. If the buffer empties, then a full frame of data (256 bits) will be repeated at RSER and the SR1.4 and RIR.3 bits will be set to a 1. If the buffer fills, then a full frame of data will be deleted and the SR1.4 and RIR.4 bits will be set to a 1. 27 of 44 DS2143/DS2143Q 11.0 ADDITIONAL (Sa) AND INTERNATIONAL (Si) BIT OPERATION The DS2143 provides for access to both the Additional (Sa) and International (Si) bits. On the receive side, the RAF and RNAF registers will always report the data as it received in the Additional and International bit locations. The RAF and RNAF registers are updated with the setting of the Receive Align Frame bit in Status Register 2 (SR2.6). The host can use the SR2.6 bit to know when to read the RAF and RNAF registers. It has 250 s to retrieve the data before it is lost. On the transmit side, data is sampled from the TAF and TNAF registers with the setting of the Transmit Align Frame bit in Status Register 2 (SR2.3). The host can use the SR2.3 bit to know when to update the TAF and TNAF registers. It has 250 s to update the data or else the old data will be retransmitted. Data in the Si bit position will be overwritten if either the DS2143 is programmed: (1) to source the Si bits from the TSER pin, (2) in the CRC4 mode, or (3) have automatic E-bit insertion enabled. Data in the Sa bit position will be overwritten if any of the TCR2.3 to TCR2.7 bits is set to 1. Please see the register descriptions for TCR1 and TCR2 and the Transmit Data Flow diagram in Section 13 for more details. RAF: RECEIVE ALIGN FRAME REGISTER (Address=2F Hex) (MSB) Si 0 0 1 1 SYMBOL POSITION NAME AND DESCRIPTION Si RAF.7 International Bit. 0 RAF.6 Frame Alignment Signal Bit. 0 RAF.5 Frame Alignment Signal Bit. 1 RAF.4 Frame Alignment Signal Bit. 1 RAF.3 Frame Alignment Signal Bit. 0 RAF.2 Frame Alignment Signal Bit. 1 RAF.1 Frame Alignment Signal Bit. 1 RAF.0 Frame Alignment Signal Bit. 28 of 44 0 1 (LSB) 1 DS2143/DS2143Q RNAF: RECEIVE NON-ALIGN FRAME REGISTER (Address=1F Hex) (MSB) Si 1 A Sa4 Sa5 Sa6 SYMBOL POSITION Si RNAF.7 International Bit. 1 RNAF.6 Frame Non-Alignment Signal Bit. A RNAF.5 Remote Alarm. Sa4 RNAF.4 Additional Bit 4. Sa5 RNAF.3 Additional Bit 5. Sa6 RNAF.2 Additional Bit 6. Sa7 RNAF.1 Additional Bit 7. Sa8 RNAF.0 Additional Bit 8. Sa7 (LSB) Sa8 NAME AND DESCRIPTION TAF: TRANSMIT ALIGN FRAME REGISTER (Address=20 Hex) (MSB) Si 0 0 1 1 SYMBOL POSITION NAME AND DESCRIPTION Si TAF.7 International Bit. 0 TAF.6 Frame Alignment Signal Bit. 0 TAF.5 Frame Alignment Signal Bit. 1 TAF.4 Frame Alignment Signal Bit. 1 TAF.3 Frame Alignment Signal Bit. 0 TAF.2 Frame Alignment Signal Bit. 1 TAF.1 Frame Alignment Signal Bit. 1 TAF.0 Frame Alignment Signal Bit. 29 of 44 0 1 (LSB) 1 DS2143/DS2143Q TNAF: TRANSMIT NON-ALIGN FRAME REGISTER (Address=21 Hex) (MSB) Si 1 A Sa4 Sa5 Sa6 SYMBOL POSITION Si TNAF.7 International Bit. 1 TNAF.6 Frame Non-Alignment Signal Bit. A TNAF.5 Remote Alarm. Sa4 TNAF.4 Additional Bit 4. Sa5 TNAF.3 Additional Bit 5. Sa6 TNAF.2 Additional Bit 6. Sa7 TNAF.1 Additional Bit 7. Sa8 TNAF.0 Additional Bit 8. Sa7 (LSB) Sa8 NAME AND DESCRIPTION 12.0 LINE INTERFACE CONTROL FUNCTION The DS2143 can control line interface units that contain serial ports. When Control Register Bytes 1 or 2 (CRB1, CRB2) are written to, the DS2143 will automatically write this data serially (LSB first) into the line interface by creating a chip select, serial clock and serial data via the LI_ CS , LI_SCLK and LI_SDI pins respectively. This control function is driven off of the RCLK and it must be present for proper operation. Registers CRB1 and CRB2 can only be written to, they cannot be read from. Writes to these registers must be at least 20 s apart. See Section 13 for timing information. CRB1: CONTROL REGISTER BYTE 1 (Address=18 Hex) CRB2: CONTROL REGISTER BYTE 2 (Address=19 Hex) (MSB) CR7 CR7 CR6 CR6 CR5 CR5 CR4 CR4 CR3 CR3 CR2 CR2 CR1 CR1 SYMBOL POSITION NAME AND DESCRIPTION CR1 CRB1.0 LSB of Control Register Byte 1. CR7 CRB2.7 MSB of Control Register Byte 2. 30 of 44 (LSB) CR0 CR0 CRB1 CRB2 DS2143/DS2143Q 13.0 TIMING DIAGRAMS RECEIVE SIDE TIMING NOTES: 1. RSYNC in the frame mode (RCR1.6=0). 2. RSYNC in the multiframe mode (RCR1.6=1). 3. RLCLK is programmed to output just the Sa4 bit. 4. RLINK will always output all 5 Sa bits as well as the rest of the receive data stream. 5. This diagram assumes the CAS MF begins with the FAS word. RECEIVE SIDE 1.544 MHZ BOUNDARY TIMING (WITH ELASTIC STORE ENABLED) NOTES: 1. Data from the E1 channels 1, 5, 9, 13, 17, 21, 25, and 29 is dropped (channel 2 from the E1 link is mapped to channel 1 of the T1 link, etc.) and the F-bit position is added (forced to 1). 2. RSYNC is in the output mode (RCR1.5=0). 3. RSYNC is in the input mode (RCR1.5=1). 4. RCHBLK is programmed to block channel 24. 31 of 44 DS2143/DS2143Q RECEIVE SIDE 2.048 MHZ BOUNDARY TIMING (WITH ELASTIC STORE ENABLED) NOTES: 1. RSYNC is in the output mode (RCR1.5=0). 2. RSYNC is in the input mode (RCR1.5=1). 3. RCHBLK is programmed to block channel 1. RECEIVE SIDE BOUNDARY TIMING (WITH ELASTIC STORE DISABLED) NOTES: 1. There is a 6 RCLK delay from RPOS, RNEG to RSER. 2. RCHBLK is programmed to block channel 2. 3. RLINK is programmed to output the Sa4 bits. 4. RLINK is programmed to output the Sa4 and Sa8 bits. 5. RLINK is programmed to output the Sa5 and Sa7 bits. 6. Shown is a non-align frame boundary. 32 of 44 DS2143/DS2143Q G.802 TIMING NOTE: 1. RCHBLK/TCHBLK is programmed to pulse high during timeslots 1 to 15, 17 to 25, during bit 1 of timeslot 26. TRANSMIT SIDE BOUNDARY TIMING NOTES: 1. 2. 3. 4. 5. 6. 7. There is a 5 TCLK delay from TSER to TPOS, and TNEG. TSYNC is in the input mode (TCR1.0=0). TSYNC is in the output mode (TCR1.0=1). TCHBLK is programmed to block channel 2. TLINK is programmed to source the Sa4 bits. TLINK is programmed to source the Sa7 and Sa8 bits. Shown is a non-align frame boundary. 33 of 44 DS2143/DS2143Q TRANSMIT SIDE TIMING NOTES: 1. TSYNC in the frame mode (TCR1.1=0). 2. TSYNC in the multiframe mode (TCR1.1=1). 3. TLINK is programmed to source only the Sa4 bit. 4. This diagram assumes both the CAS MF and the CRC4 begin with the align frame. LINE INTERFACE CONTROL TIMING NOTES: 1. A write to CRB1 will cause the DS2143 to output this sequence. 2. A write to CRB2 will cause the DS2143 to output this sequence. 3. Timing numbers are based on RCLK=2.048 MHz with 50% duty cycle. 34 of 44 DS2143/DS2143Q DS2143 SYNCHRONIZATION FLOWCHART 35 of 44 DS2143/DS2143Q DS2143 TRANSMIT DATA FLOW 36 of 44 DS2143/DS2143Q ABSOLUTE MAXIMUM RATINGS* Voltage on Any Pin Relative to Ground Operating Temperature Storage Temperature Soldering Temperature * -1.0V to +7.0V 0C to 70C -55C to +125C 260C for 10 seconds This is a stress rating only and functional operation of the device at these or any other conditions above those indicated in the operation sections of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods of time may affect reliability. RECOMMENDED DC OPERATION CONDITIONS PARAMETER Logic 1 Logic 0 Supply (0C to 70C) SYMBOL VIH VIL VDD MIN 2.0 -0.3 4.5 TYP MAX VDD+0.3 +0.8 5.5 UNITS V V V NOTES SYMBOL CIN COUT MIN TYP 5 7 MAX UNITS pF pF NOTES SYMBOL IDD IIL ILO IOH IOL MIN CAPACITANCE PARAMETER Input Capacitance Output Capacitance (0C to 70C; VDD = 5V 10%) DC CHARACTERISTICS PARAMETER Supply Current Input Leakage Output Leakage Output Current (2.4V) Output Current (0.4V) NOTES: 1. RCLK = TCLK = 2.048 MHz; VDD = 5.5V. 2. 0.0V < VIN < VDD. 3. Applies to INT1 and INT2 when 3-stated. 37 of 44 -1.0 -1.0 +4.0 TYP 10 MAX +1.0 1.0 UNITS mA A A mA mA NOTES 1 2 3 DS2143/DS2143Q AC CHARACTERISTICS - PARALLEL PORT PARAMETER Cycle Time Pulse Width, DS Low or RD High Pulse Width, DS High or RD Low Input Rise/Fall Times R/ W Hold Time R/ W Setup Time Before DS High CS Setup Time Before DS, WR or RD active CS Hold Time Read Data Hold Time Write Data Hold Time Muxed Address Valid to AS or ALE Fall Muxed Address Hold Time Delay Time, DS, WR or RD to AS or ALE Rise Pulse Width AS or ALE High Delay Time, AS or ALE to DS, WR or RD Output Data Delay Time from DS or RD Data Setup Time (0C to 70C; VDD = 5V + 10%) SYMBOL tCYC PWEL PWEH tR, tF tRWH tRWS tCS MIN 250 150 100 10 50 20 UNITS ns ns ns ns ns ns ns tCH tDHR tDHW tASL tAHL tASD 0 10 0 20 10 25 ns ns ns ns ns ns PWASH tASED tDDR tDSW 40 20 20 80 38 of 44 TYP MAX 30 50 100 ns ns ns ns NOTES DS2143/DS2143Q INTEL WRITE AC TIMING INTEL READ AC TIMING MOTOROLA AC TIMING 39 of 44 DS2143/DS2143Q AC CHARACTERISTICS - TRANSMIT SIDE PARAMETER TCLK Period TCLK Pulse Width TSER, TSYNC, TLINK Setup to TCLK Falling TSER, TLINK Hold from TCLK Falling TCLK Rise/Fall Times Data Delay TSYNC Pulse Width SYMBOL tP tCH tCL tSU MIN tHD t R , tF tDD tPW 25 AC CHARACTERISTICS - RECEIVE SIDE PARAMETER RCLK and SYSCLK Period RCLK and SYSCLK Pulse Width RPOS, RNEG, RSYNC Setup to RCLK Falling RPOS, RNEG, Hold from RCLK Falling RCLK Rise/Fall Times Data Delay RSYNC Pulse Width (0C to 70C; VDD = 5V 10%) 50 50 25 25 50 50 UNITS ns ns ns ns NOTES ns ns ns ns (0C to 70C; VDD = 5V =10%) SYMBOL tP tCH tCL tSU MIN tHD tR , t F tDD tPW 25 40 of 44 TYP MAX 488 TYP MAX 488 50 50 25 25 60 50 UNITS ns ns ns ns ns ns ns ns NOTES DS2143/DS2143Q TRANSMIT SIDE AC TIMING NOTES: 1. TSYNC is in the output mode (TCR1.0=1). 2. TSYNC is in the input mode (TCR1.0=0). 3. No timing relationship between TSYNC and TLCLK/TLINK is implied. 41 of 44 DS2143/DS2143Q RECEIVE SIDE AC TIMING NOTES: 1. RSYNC is in the output mode (RCR1.5=0). 2. RSYNC is in the input mode (RCR1.5=1). 3. No timing relationship between RSYNC and RLCLK/RLINK is implied. 42 of 44 DS2143/DS2143Q DS2143 E1 CONTROLLER (600 MIL) 40-PIN DIP DIM A B C D E F G H J K INCHES MIN MAX 2.040 2.070 0.530 0.560 0.145 0.155 0.600 0.625 0.015 0.040 0.120 0.140 0.090 0.110 0.625 0.675 0.008 0.012 0.015 0.022 43 of 44 DS2143/DS2143Q DS2143 E1 CONTROLLER 44-PIN PLCC NOTE1: PIN 1 IDENTIFIER TO BE LOCATED IN ZONE INDICATED. DIM A A1 A2 B B1 C CH1 D D1 D2 E E1 E2 e1 N INCHES MIN MAX 0.165 0.180 0.090 0.120 0.020 0.026 0.033 0.013 0.021 0.009 0.012 0.042 0.048 0.685 0.695 0.650 0.656 0.590 0.630 0.685 0.695 0.650 0.656 0.590 0.630 0.050 BSC 44 - 44 of 44