comtech aha corporation Product Specification AHA4210 RSVP Viterbi with Reed-Solomon Decoder PS4210_1099 A subsidiary of Comtech Telecommunications Corporation 2345 NE Hopkins Court Pullman WA 99163 tel: 509.334.1000 fax: 509.334.9000 www.aha.com comtech aha corporation Notes to Customers of AHA4210 1. Patent(s) pending. One or more patent(s) have been applied for this product. 2. Purchase of I2C components of AHA conveys a license under the Philips I2C Patent Rights to use these components in an I2C system, provided that the system conforms to the I2C Standard Specification as defined by Philips. Page 2 of 2 PS4210_1099 comtech aha corporation Table of Contents 1.0 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1.1 Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1.2 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1.3 Conventions and Notations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1.4 Definition of Terms and Programmability. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 2.0 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 2.1 Synchronization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 2.1.1 Explanation of Clocking Schemes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 2.2 Viterbi Decoder . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 2.2.1 Depuncture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 2.3 Deinterleaver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 2.4 RS Decoder . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 2.5 Derandomize/Energy Dispersal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 2.6 Modes of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 2.7 Microprocessor Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 2.7.1 Parallel 80C188 Microprocessor Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 2.7.2 Serial I2C Protocol Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 2.8 Latency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 3.0 Register Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 3.1 Register Summary. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 3.2 ERRSTAT: Error Count Status . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 3.3 ERRSIZE: Error Block Count. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 3.4 VRSSIZE: Total Block Count for VRSTH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 3.5 VSYNCP: Sync Decoder Pattern. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 3.6 VRSTH: RS Uncorrectable Blocks Threshold . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 3.7 VERTH: Sync Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 3.8 VCON: Viterbi Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 3.9 MSGBYTES2: Message Bytes K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 3.10 RSEED0: Derandomizer Seed LSB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 3.11 RSEED1: Derandomizer Seed MSB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 3.12 IOCNTRL: Input/Output Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 3.13 NJL: Block Length Times Interleave Depth LSB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 3.14 NJM: Block Length Times Interleave Depth MSB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 3.15 BLKLEN2: RS Block Length N . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 3.16 JDEPTH: Interleave Depth . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 3.17 RSCONTROL: Reed-Solomon Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 4.0 Signal Descriptions and Specifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 4.1 Input Signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 4.2 Output Signals. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 4.3 Bidirectional Signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 4.4 Input Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 4.5 Output Specifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 4.6 Bidirectional Pin Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 4.7 Power & Ground Pins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 4.8 Pinout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 5.0 Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 6.0 DC Electrical Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 7.0 Packaging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 8.0 Ordering Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 8.1 Available Parts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 8.2 Part Numbering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 9.0 AHA Related Technical Publications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 10.0 Other Technical Publications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 PS4210_1099 A subsidiary of Comtech Telecommunications Corporation i comtech aha corporation Figures Figure 1: Figure 2: Figure 3: Figure 4: Figure 5: Figure 6: Figure 7: Figure 8: Figure 9: Figure 10: Figure 11: Figure 12: Figure 13: Figure 14: Figure 15: Figure 16: Figure 17: Figure 18: Figure 19: Figure 20: Figure 21: Figure 22: ii AHA4210 Block Diagram. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 I2C Internal Register Increment Example, Writing the Registers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 I2C Reading Internal Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Bit Transfer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Start and Stop Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Clock Timing - SCLK and VCLK . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Reset Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 DATAFLUSH Timing - Byte Input Mode. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 Microprocessor Write Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 Microprocessor Read Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 I2C Interface Timing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 Input - Serial Mode: IOCNTRL[2:1] = 0x Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Input - Byte Mode: IOCNTRL[2:1] = 10 Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Input - Byte Mode IOCNTRL[2:1] = 11 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 Output - BCLK Mode: IOCNTRL[4:3] = 10, [2:1] = 11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 Output - Byte Mode: IOCNTRL[4:3] = 10, IOCNTRL[2:1] 11 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 IOCNTRL[4:3] = 00, Serial Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 IOCNTRL[4:3] = 01, Serial Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 IOCNTRL[4:3] = 10, Byte Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 IOCNTRL[4:3] = 11, Byte Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 Power vs. VCLK Rate, Estimated for Modes 1 and 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 Max Ambient Temperature (Ta) vs. VCLK Rate, Estimated for Modes 1 and 3. . . . . . . . . . . . . . . . . . . . 27 A subsidiary of Comtech Telecommunications Corporation PS4210_1099 comtech aha corporation Tables Table 1: Table 2: Table 3: Various Modes Supported by the AHA4210 Device . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Register Settings for Functional Block Bypass . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Maximum Latency in VCLK Cycles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 PS4210_1099 A subsidiary of Comtech Telecommunications Corporation iii comtech aha corporation 1.0 INTRODUCTION The AHA4210, referred to as the RSVP, is a single-chip Forward Error Correction LSI device combining a Viterbi decoder, a Reed-Solomon decoder, a descrambler (energy dispersal) and a deinterleaver. The device conforms to the MPEG-II transport layer protocol specified by ISO/IEC standard and FEC requirements of Digital Video Broadcasting (DVB) DT/8622/DVB and DT/8610/ III-B specification. These documents are referred to as the DVB specification. The Viterbi decoder supports selectable code rates of 1/2, 2/3, 3/4, 5/6, 6/7 or 7/8 using industry standard puncturing algorithms. Viterbi decoded data rate is up to 62 Mbits/second at all code rates. The chip also performs byte alignment and block/ packet synchronization detecting sync bytes used in transmission. The descrambling function is selectable with a programmable seed or performed externally. Each functional block may be bypassed giving more flexibility to a system designer. Block size programmability, several code rate choices and programmable RS error correction capability allows flexibility to a digital communications system designer incorporating Forward Error Correction into a receiver. Intel 80C188 multiplexed parallel or serial I2C protocol interface allows the system microprocessor to program internal registers and monitor channel performance. This document contains key features, correction terms, functional description, signal functions, Related Technical Publications, DC and AC characteristics, pinout, package dimension and ordering information. 1.1 APPLICATIONS * Satellite communications/VSAT * DBS * Military Communications 1.2 FEATURES GENERAL: * Conforms to the ISO/IEC-CD 13818-1 MPEG-II transport layer protocol and Digital Video Broadcasting (DVB)FEC specification * Viterbi decoded data rates up to 62 Mbits/sec at any code rate * Programmable block size from 34 to 255 bytes * Multiplexed parallel Intel 80C188 or serial I2C protocol microprocessor interface * Byte or serial data output * On-Chip error rate monitor PS4210_1099 * Programmable bypass modes for each of the major blocks * Configured to DVB mode of operation on powerup * 68 pin PLCC VITERBI DECODER: * Selectable decoder rates 1/2, 2/3, 3/4, 5/6, 6/7 and 7/8 or automatic acquire mode * 3-Bit soft-decision decoder inputs * Constraint length k=7 SYNCHRONIZATION CONTROL: * Automatic synchronization capability for QPSK based demodulator * Up to one sync byte per block * Responds to inverted sync byte REED-SOLOMON: * t=1 through 8 in increments of 0.5 * Correction capability of up to 8 bytes * Internal FIFOs DEINTERLEAVER: * Programmable convolutional deinterleaving (Ramsey II, Ramsey II modified or Forney) to depth I=16 * No external RAM required ENERGY DISPERSAL: * Selectable on-chip DVB specification Energy Dispersal * Optional bypass mode * Programmable seed 1.3 CONVENTIONS AND NOTATIONS - Certain signals are logically true at a voltage defined as "low" in the data sheet. All such signals have an "N" appended to the end of the signal name. For example, RSTN and RDYON. - "Signal assertion" means the signal is logically true. - Hex values are defined with a prefix of "0x", such as "0x10". - A range of signal names is denoted by a set of colons between the numbers. Most significant bit is always shown first, followed by least significant bit. For example, ERRSTAT[6:0] represents number of bytes corrected by the ReedSolomon decoder. - A product of two variables is expressed with an "x", for example, BLKLEN2 x JDEPTH represents Block Length multiplied by Interleave Depth. - Megabytes per second is referred to as MBytes/ sec or MB/sec. Megabits per second is referred as Mbits/sec or Mb/sec. - Frequency of a clock signal is referred to as F(name). For example, F(VCLK) specifies frequency of VCLK. A subsidiary of Comtech Telecommunications Corporation Page 1 of 30 comtech aha corporation 1.4 DEFINITION OF TERMS AND PROGRAMMABILITY VITERBI NAME (other references) TERM k Constraint Length Traceback Depth Puncturing Puncture Pattern Convolutional Code Rate (Puncture Rate) DEFINITION RANGE Number of input bits over which convolutional code is computed. Length of path through the trellis over which the Viterbi decoder computes the likelihood of a decoded bit value. Process of deriving a higher rate code from a basic rate code. Mapping between 1/2 rate encoded bits and new higher rate encoded bits. Ratio of input to output bits for convolutional code. 7 minimum=115 N/A N/A 1/2, 2/3, 3/4, 5/6, 6/7, 7/8 DEINTERLEAVER TERM J NAME (other references) Ramsey or Forney Interleave Depth DEFINITION RANGE Convolutional interleave techniques. Minimum separation in the interleaved stream. N/A 1 through 16 REED-SOLOMON NAME (other references) TERM K R N t DEFINITION RANGE Number of user data symbols in one message block. Message Length (user Size of a symbol in AHA4210 is 8-bits. Message data or message bytes) length is K = N - R . Symbols appended to the user data to detect and correct errors. The number of check symbols Check symbols (parity or redundancy) required in a system is R 2e . Every 2 check bytes correct 1 error byte. Codeword Length Sum of message and check symbols. N = K + R . (block length) 2 thru 16 bytes in increments of 1 (2, 3, 4 . . . 16) 34 thru 255 bytes (34, 35, 36 . . . 255) 1 thru 8 bytes in increments of 0.5 (1, 1.5, 2, 2.5 . . . 8) Error Corrections Maximum number of error corrections performed N - K- . by the device. The value is t=Integer ------------- Number of Errors An error is defined as an erroneous byte whose correct value and position within the message block minimum 0 are both unknown. RS Code Rate Ratio of message to block length, K ---- . 2 e 32 thru 253 bytes (32, 33, 34 . . . 253) N 0.67 through 0.99 GENERAL NAME (other references) TERM Bypass Block Packet Page 2 of 30 DEFINITION RANGE Processing data either through or around a N/A functional block. An entity of both message and Reed-Solomon check (34, 35, . . . 255) bytes. The number of message bytes is equal to the bytes length of the MPEG-II packet for a DVB system. 188 including one MPEG-II transport layer packet size. sync mark byte A subsidiary of Comtech Telecommunications Corporation PS4210_1099 comtech aha corporation 2.0 FUNCTIONAL DESCRIPTION This section presents an architectural overview of the chip and its many functions, features and operating modes. Block diagram of the chip shows the Viterbi and Reed-Solomon decoder modules. Figure 1: AHA4210 Block Diagram BYTE[1:0] MUX I[2:0] IQSTRB Q[2:0] DEINTERLEAVER & RAM VITERBI DECODER INPUT DEPUNCTURING INTERFACE LOGIC BLKNEW REED-SOLOMON DECODER & ENGERY DISPERSAL (DESCRAMBLER) DO[7:0] RDYON BLKERR SCLK DATAFLUSH SYNC CONTROL RSTN 2.1 SYNCHRONIZATION This module synchronizes data received from Viterbi to byte and packet boundaries. The synchronization algorithm is summarized below. Bit-to-byte mapping is performed while looking for sync marks specified in register VSYNCP. Every bit position is examined for a sync mark byte. If no sync mark is detected after looking for a minimum of two block lengths, then the phase is incremented and the process is repeated. Carrier and depuncture phases are cycled through searching for sync marks. This process terminates when sync is achieved. After a sync mark is detected, additional sync marks as specified in SYNCON[2:0] are searched. Detection of additional sync completes the block sync process and data is output on the next inverted sync (or regular sync if VCON[7] = 0). Once the output data flow starts, consecutive sync marks are required if enabled by the VCON[6] to remain in sync. In this case if SYNCOFF[2:0] consecutive sync marks are missed, then the block goes out of the sync condition. The block may also go out of sync if the ReedSolomon uncorrectable blocks threshold is exceeded over a programmable number of blocks. This feature is enabled by VCON[5]. Total Block Count and Threshold are programmed by VRSSIZE and VRSTH registers. PS4210_1099 2.1.1 BCLK VCLK DECODER CLOCK CONTROL READY MAL MCSN MD[7:0] MWRN MRDN SDA SCL MICROPROCESSOR INTERFACE DECODER CONTROL EXPLANATION OF CLOCKING SCHEMES The Viterbi block has two clock inputs: SCLK and VCLK. VCLK runs the actual Viterbi decoder block while SCLK simply drives the input stage for Viterbi. The data inputs I[2:0], Q[2:0] and IQSTRB are synchronous to SCLK. There are two approaches to using this interface. Approach one involves tying IQSTRB to VDD (active) and assuring that: VCLK Frequency ( SCLK ) Frequency ----------------- 2 x CR Where CR is defined as the code rate. Note that this is a strict requirement and the chip will enter a state requiring a hard reset if this is not met. One advantage to this approach is that in some designs SCLK is already available and I and Q are already synchronous to this signal. The other method is to tie SCLK and VCLK together and throttle the data with IQSTRB. For any --- , where Y is even, IQSTRB would given code rate X Y be held high (clocking in I[2:0] and Q[2:0] on that cycle) for no more than --Y2- out of every X clocks. If Y is odd then IQSTRB would be held high for no more than Y out of every 2X clocks and no more than Y + 1- in every X clock cycles. ----------2 In the final approach it is not necessary to supply a separate clock (SCLK), however, the customer must supply the circuitry to drive IQSTRB appropriately. A subsidiary of Comtech Telecommunications Corporation Page 3 of 30 comtech aha corporation The Viterbi decoder can be set up to cycle through all convolutional code rates. In this case, use convolutional code rate 7/8 in the equation: F ( VCLK ) F ( SCLK ) -----------------------2 x CR 2.2 VITERBI DECODER The Viterbi decoder takes the data from an I and a Q channel and decodes these using a 3 bit soft decision. The Viterbi decoder is based on a 1/2 rate code, but also supports punctured codes with rates: 2/3, 3/4, 5/6, 6/7 and 7/8. The generator polynomials are: g1 = 171(octal) and g2 = 133(octal) The minimum trace back depth is 115. The output of the Viterbi decoder is converted to 8 bit bytes, sync bytes are detected and after which the data is run through the deinterleaver to restore the ECC blocks. The Viterbi decoder can be bypassed by bit 2 of the IOCNTRL and disabled by bit 4 of the VCON register. The latency of the Viterbi block is measured in two ways. First, there is a latency associated with "synching" to the incoming signal. Assuming that there is no valid sync byte patterns in the data the worst case sync time is given by: ( 8 x block length + 384 ) x 4 x ( # of puncture phases ) + 512 This assumes that SCLK runs fast enough to keep the data pipeline full. Once the Viterbi block is synched up, the maximum latency from input to output is 258 VCLK cycles. 2.2.1 DEPUNCTURE The Viterbi module can be programmed to depuncture according to a specified code rate or automatically find the code rate used in the channel. Following is a list of puncture patterns and number of phases that are cycled through in an attempt to align the puncture phase. RATE 1/2 2/3 3/4 5/6 6/7 7/8 Page 4 of 30 PATTERN: X:Y X Y X Y X Y X Y X Y X Y 1 1 10 11 101 110 10101 11010 100101 111010 1000101 1111010 # OF PHASES 1 3 During the encoding process, X and Y are mapped into I and Q by taking the nondeleted terms in order of X1, Y1, X2, Y2, etc. Deleted terms are simply skipped. The decoding process is simply the reverse of this procedure. Erasures are inserted on the pattern locations with zeroes. For example, the rate 5/6 I and Q have values: I = X1, Y2, Y4, X1, Y2, Y4, . . . Q = Y1, X3, X5, Y1, X3, X5, . . . The chip is capable of supporting a limited number of depuncture codes not included in this specification. The procedure for supporting these codes are beyond the scope of this specification. Please contact AHA Applications Engineering for these codes. The Viterbi core can be configured to self synchronize to the appropriate depuncture pattern ----- phase ambiguity. If phase and correct for pi 2 VRSSIZE[6] is set, Viterbi sync does not cycle through carrier phases. If the code rate is not known, the core can also be configured to cycle through 1/2, 2/3, 3/4, 5/6, 6/7 and 7/8 code rates looking for a valid pattern. 2.3 DEINTERLEAVER The deinterleaver supports a variety of programmed options: TECHNIQUE APP INTERLEAVE DVB Forney/ Ramsey III Ramsey II 3 Ramsey II modified 4 WITH WITHOUT VITERBI VITERBI Ramsey II No Yes Forney/Ramsey III Yes Yes Modified Ramsey II Yes Yes A Ramsey type II interleaver is specified in J.L. Ramsey, "Realization of Optimal Interleavers," IEEE Transaction on Information Theory, May 1970, pp. 338-345. A Forney/Ramsey type III interleaver is specified in DVB DT/8622/DVB specification. The interleave depth is programmable up to 16 packets and the block size is programmable up to 255 bytes. However, the product of the interleave depth and block length cannot be larger than 2688 bytes. In addition to this, the following conditions must be satisfied for various applications. 2 7 TYPE CONSTRAINT BLKLEN2/JDEPTH[3:0] must be an integer BLKLEN and JDEPTH[3:0] must be relatively prime Same as Ramsey II Maximum processing latency = 8 x ( NJM[3:0] & NJL[7:0] ) VCLKS Note that the "&" is a concatenation symbol. A subsidiary of Comtech Telecommunications Corporation PS4210_1099 comtech aha corporation 2.4 RS DECODER The RS block performs the outer decoding. The Reed-Solomon decoder conforms to the DVB specification. The RS block can be programmed to decode t=1, 1.5, 2, . . . 7.5, 8. p ( x ) = x8 + x4 + x3 + x2 + 1 0 1 g ( x ) = ( x + ) ( x + ). . . ( x + ( 2t - 1 ) ) 1 = primitive element The block length of the code is programmable up to 255 bytes. Block length is 204 with 16 check bytes and a correction power of 8 bytes per block for the DVB specification. Maximum latency through the RS Decoder Block is: ( N - 1 ) x 8 + 120 + 2R + N x 2.67 2.5 DERANDOMIZE/ENERGY DISPERSAL The derandomizer is specified in the DVB specification. It is built as a 15 stage pseudo-random binary sequence generator with initialization sequence specified by RSEED0 and RSEED1 registers. The randomization occurs over 8 blocks of MGSBYTES2 (188 bytes for DVB specification). Randomization does not occur over Table 1: 2.6 MODES OF OPERATION The FEC decoder has been designed with a modular approach so that each of the four major functions: Viterbi decoding, deinterleaving, RS decoding and derandomization can be individually enabled or disabled. Five operating modes are supported by the device. These are: 1) Normal mode. All functions enabled. Inputs clocked with SCLK. 2) Byte Input mode. All functions except Viterbi enabled. Inputs clocked with VCLK. Tie SCLK to VCLK. Use Byte [1:0], I[2:0] and Q[2:0] as byte wide data path. Bytes must arrive on packet boundaries. 3) Viterbi decode mode. Inputs clocked with SCLK. 4) Reed-Solomon decode mode. Same input constraints as byte input mode. 5) Deinterleave mode. Same input constraints as byte input mode. These modes may be operated with or without the derandomizer enabled. Various Modes Supported by the AHA4210 Device MODE 1) 2) 3) 4) 5) Reed-Solomon parity bytes nor sync bytes. However, the pseudo-random binary sequence generator continues to run during non-inverted sync bytes. Maximum latency = 10 VCLKs. Normal Byte Input Viterbi Decode RS Decode Deinterleaver Table 2: VITERBI Enabled Disabled Enabled Disabled Disabled DERANDOMIZER Enabled Enabled Disabled Disabled Enabled Either Either Either Either Either Enabled Enabled Disabled Enabled Disabled Register Settings for Functional Block Bypass FUNCTIONAL BLOCK Viterbi Deinterleaver Reed-Solomon Derandomizer PS4210_1099 FUNCTIONAL BLOCK DEINTERLEAVER RS DECODER ENABLED VCON[4]=1 IOCNTRL[2]=0 JDEPTH[4]=1 RSCONTROL=0C IOCNTRL[7]=1; VCON[7]=1 DISABLED VCON[4]=0 IOCNTRL[2]=1 JDEPTH[4]=0 RSCONTROL=1C IOCNTRL[7]=0; VCON[7]=0 A subsidiary of Comtech Telecommunications Corporation Page 5 of 30 comtech aha corporation 2.7 MICROPROCESSOR INTERFACE The device is capable of interfacing to a multiplexed eight bit bus or the I2C serial interface. The system microprocessor is referred to as the host and behaves as a "master" and the AHA device is a "slave." 2.7.1 PARALLEL 80C188 MICROPROCESSOR INTERFACE The parallel interface supports an Intel 80C188 microprocessor with a multiplexed address and data bus. For a register read operation the chip select (MCSN) is asserted. The device asserts the READY signal low. This is followed by the host outputting the register address on the MD[7:0] bus along with the address latch enable (MAL). The host then asserts the read strobe (MRDN). The device responds by outputting the data on the MD[7:0] bus and tristating the READY signal. Valid data is available when READY is tristated by the device. Bus cycle is terminated by the host deasserting the MRDN signal. A register write operation is similar to the register read except the host asserts the MWRN strobe along with the data. The device then loads the data into the appropriate register and tristates the READY signal. The bus cycle terminates when the MWRN strobe gets deasserted. When using the parallel interface tie the SCL and the SDA signals high. MCSN must not glitch. 2.7.2 In high speed mode, the first two bytes between a host and a slave device determine the device selected. These two bytes are the first two bytes following the Start condition as shown in Figure 5. The bytes contain: 1, 1, 1, 1, 0, AD4, AD3, R/W, and AD2, AD1, AD0, A4, A3, A2, A1, A0. AD[4:0] = Slave ID address A[4:0] = Register address R/W = Direction of data transfer where: 1 = Read; 0 = Write When programming the registers in I2C mode, the device performs auto increment of internal addresses. All 16 addresses may be accessed by writing 21 values to Address 0x00 as shown in Figure 2. Alternatively a register may be randomly accessed by specifying its address, such as 0x04. Figure 2 is an example of writing to one or more registers. Figure 3 is an example of reading a register. The serial I2C interface protocol conforms to the I2C Bus Specification. For electrical performance of this interface, please refer to the Timing section. Notes: 1) This document contains a very brief description of the I2C Bus functions. For a detailed description, please refer to Specification documents available from Philips. 2) I2C Bus protocol supported by AHA4210 requires a 10-bit addressing. 3) See Note 2 on back of cover page. 2 SERIAL I C PROTOCOL INTERFACE The I2C interface is a serial microprocessor interface using two signals named SCL and SDA. Any drivers connected to these signals must be open drain or open collector to facilitate the wired-AND operation of this bus. There is one SCL pulse per data bit and the SDA line must be stable during the high period of the SCL pulse, changing only when SCL is low for data transfers. In a target design using the I2C serial interface, the following connections need to be made. Connect MRDN and MWRN to Ground. Tie MCSN high and connect MAL to Ground. The lower five bits of the MD[7:0] bus need to be hardwired to the correct Slave ID address. For example, if a Slave ID address of 5 is needed, connect bits 0 and 2 to VDD, and bits 1, 3 and 4 to Ground. The following paragraphs describe briefly the serial communication over this bus. For more detailed information please refer to the I2C Bus Specification listed in the Related Technical Publications section. This device works in either high speed mode or standard low speed mode. Page 6 of 30 A subsidiary of Comtech Telecommunications Corporation PS4210_1099 comtech aha corporation Figure 2: 2 I C Internal Register Increment Example, Writing the Registers ST 1 1 1 1 0 AD4 AD3 R/W ACK Acknowledge Direction MSB's of ID Address (Hard Wired) Special Code for 10-bit Addressing Start Condition AD2 AD1 AD0 A4 A3 A2 A1 A0 ACK Acknowledge 5 bits of Internal Register Addressing (Start Address) 3 LSB's of ID Address (Hard Wired) BYTE 0 ACK BYTE 1 ACK Data BYTE 2 ACK STP Stop Condition An `ACK' is generated by the master device on termination of read operation. Figure 3: 2 I C Reading Internal Registers ST 1 1 1 1 0 AD4 AD3 R/W ACK Write, Set to 0 AD2 AD1 AD0 A4 A3 A2 A1 A0 ACK Internal Register Address Sr 1 1 1 1 0 AD4 AD3 R/W ACK Read, Set to 1 Repeated Start Register Read Data PS4210_1099 ACK STP A subsidiary of Comtech Telecommunications Corporation Page 7 of 30 comtech aha corporation Figure 4: Bit Transfer SDA SCL Figure 5: Start and Stop Conditions Acknowledge SDA MSB SCL 1 2 8 9 Start Condition 2.8 Stop Condition Table 3: LATENCY Maximum latency measured in VCLK cycles through the various blocks is summarized in Table 3. Page 8 of 30 Maximum Latency in VCLK Cycles FUNCTIONAL BLOCK LATENCY Viterbi Deinterleaver RS Decoder Derandomizer 258 (after sync has been acquired) 8 x (NJM[3:0] & NJL[7:0]) (N-1)x8+120+2R+Nx2.67 10 A subsidiary of Comtech Telecommunications Corporation PS4210_1099 comtech aha corporation 3.0 REGISTER DESCRIPTION This section contains a summary and a description of registers. Unless otherwise specified, all registers are Read/Write. The following registers can be changed during operation: ERRSIZE, VRSSIZE[5:0], VSYNCP, VRSTH, VERTH, VCON[3:0], RSEED0 and RSEED1. The other registers must be programmed before the first data is input to the AHA4210 after a reset. 3.1 REGISTER SUMMARY FUNCTIONAL ADDRESS BLOCK 0x00 0x01 0x02 0x03 Viterbi and 0x04 Synchronizer 0x05 0x06 0x07 0x08 Derandomizer 0x09 0x0A 0x0B 0x0C Deinterleaver 0x0D 0x0E Error Monitor Reed-Solomon 0x0F MNEMONIC REGISTER NAME RESET VALUE ERRSTAT ERRSIZE VRSSIZE VSYNCP VRSTH VERTH VCON MSGBYTES2 RSEED0 RSEED1 IOCNTRL NJL NJM BLKLEN2 JDEPTH RES RES CHKBYTES MSGBYTES BLKLEN RSCONTROL Error Count Total Block Count for ERRSTAT Total Block Count for VRSTH Sync Decoder Pattern Reed-Solomon Uncorrectable Blocks Threshold Sync Control Viterbi Control Message bytes, k Derandomizer seed, LSB Derandomizer seed, MSB Input/Output Control Block Length times Interleave Depth, LSB Block Length times Interleave Depth, MSB Reed-Solomon Block Length, N Interleave Depth Reserved Reserved Check bytes Message bytes Block Length Reed-Solomon Control 0x00 0x20 0x18 0x47 0x08 0x27 0xB3 0xBC 0xA9 0x00 0x90 0x90 0x09 0xCC 0x1C 0xFF 0xFF 0x90 0xBC 0xCC 0x0C Notes: 1) Reed-Solomon registers, address 0x0F, are Write only. All other registers are Read/Write. 2) All six registers of the Reed-Solomon block must be programmed consecutively. Write to address 0x0F accesses these registers. 3) On Reset, the AHA4210 device is configured for DVB specification operation. 3.2 ERRSTAT: ERROR COUNT STATUS Address: 0x00; BIT 7 6:0 Reset Value = 0x00 DESCRIPTION 1 = One or more blocks within ERRSIZE is flagged uncorrectable. Bits [6:0] values do not represent total corrected locations. 0 = Errors have been corrected. Bits [6:0] represent total corrected locations. Number of bytes corrected by RS in ERRSIZE blocks. These bits should be ignored when bit [7] is set to `1' or when RS is bypassed. If the number of errors exceeds 126, then the value in this register saturates at 127. PS4210_1099 A subsidiary of Comtech Telecommunications Corporation Page 9 of 30 comtech aha corporation 3.3 ERRSIZE: ERROR BLOCK COUNT Address: 0x01; Reset Value = 0x20 BIT DESCRIPTION 7:0 3.4 Total number of blocks over which ERRSTAT counts corrected bytes by Reed-Solomon. VRSSIZE: TOTAL BLOCK COUNT FOR VRSTH Address: 0x02; Reset Value = 0x18 BIT DESCRIPTION 7 6 Reserved. Set to `0'. If set, then Viterbi sync does not cycle through carrier phases. The number of total blocks over which the number of uncorrectable blocks is counted and compared to the VRSTH value. 5:0 3.5 VSYNCP: SYNC DECODER PATTERN Address: 0x03; Reset Value = 0x47 BIT DESCRIPTION 7:0 3.6 The value of the sync byte. The inverted sync value is derived from VSYNCP. VRSTH: RS UNCORRECTABLE BLOCKS THRESHOLD Address: 0x04; Reset Value = 0x08 BIT DESCRIPTION 7:4 3:0 3.7 Reserved. Set to `0'. RSOFF is Reed-Solomon uncorrectable blocks threshold. VERTH: SYNC CONTROL Address: 0x05; BIT 7 6:4 3 2:0 Reset Value = 0x27 DESCRIPTION Reserved. Set to `0'. SYNCON is the number of sync bytes that must be detected before the synchronization block claims synchronization has been achieved. Minimum value is 2. Values of 0 and 1 are illegal and result in unknown operation. See Inverted Sync Note. Specify mapping number on the input signal. 0 = mapping #1 0 = strongest zero, 3 = weakest zero 4 = weakest one, 7 = strongest one 1 = mapping #2 3 = strongest zero, 0 = weakest zero 4 = weakest one, 7 = strongest one SYNCOFF is the number of sync bytes that must be missed before the synchronization block claims synchronization has been lost. 0 is illegal. See Inverted Sync Note. Inverted Sync Note: When the SYNCON value is set to `010' and VCON[7]=1, the AHA4210 can sync onto an inverted data stream, such as can occur if the demod is 180 degrees out of phase. When SYNCOFF value is set to `111' and VCON[7:5] is set to `110' or `100', the AHA4210 does not go out of sync when an inverted data stream occurs. In either case, enabling the Reed-Solomon error rate control over resynchronization VCON[5] causes the AHA4210 to recover from these conditions. Page 10 of 30 A subsidiary of Comtech Telecommunications Corporation PS4210_1099 comtech aha corporation 3.8 VCON: VITERBI CONTROL Address: 0x06; Reset Value = 0xB3 BIT DESCRIPTION 7 1 = enable, 0 = disable inverted sync detection. 1 = enable, 0 = disable resynchronization if the missed sync byte threshold (SYNCOFF) is exceeded. See Burst Error Note. 1 = enable, 0 = disable Reed-Solomon error rate control over resynchronization (VRSTH, VRSSIZE). 1 = enable, 0 = disable Viterbi decoder. This does not provide a bypass mode. It turns off the Viterbi for power savings. 1 = hard, 0 = soft decision input. Puncture rate: 0 = automatic puncture detection 1 = 1/2 rate 2 = 2/3 rate 3 = 3/4 rate 4 = reserved 5 = 5/6 rate 6 = 6/7 rate 7 = 7/8 rate 6 5 4 3 2:0 Burst Error Note: When the resynchronization of the AHA4210 is controlled only by the Reed-Solomon error rate control and a burst of all input values are zero of any strength, then the Reed-Solomon receives a valid codeword (of all 0s). In this case, the AHA4210 does not go out of sync during the burst and does not flag the output as uncorrectable. If this condition is unacceptable, enable the missed sync byte resynchronization mechanism, VCON[6]. 3.9 MSGBYTES2: MESSAGE BYTES K Address: 0x07; Reset Value = 0xBC BIT 7:0 DESCRIPTION Set equal to MSGBYTES. This value is used by the derandomizer module. 3.10 RSEED0: DERANDOMIZER SEED LSB Address: 0x08; Reset Value = 0xA9 BIT 7:0 DESCRIPTION Least significant byte of derandomizer seed. 3.11 RSEED1: DERANDOMIZER SEED MSB Address: 0x09; BIT 7 6:0 Reset Value = 0x00 DESCRIPTION Reserved. Set to `0' Most significant byte of derandomizer seed. PS4210_1099 A subsidiary of Comtech Telecommunications Corporation Page 11 of 30 comtech aha corporation 3.12 IOCNTRL: INPUT/OUTPUT CONTROL Address: 0x0A; Reset Value = 0x90 BIT 7 6 5 4 3 2:1 0 DESCRIPTION 1 = Enable derandomization. 0 = Bypass derandomization. 1 = Output check bytes. 0 = Do not output check bytes. 1 = Set error flag in packet header according to ISO/IEC CD 13818-1 (MPEG-II). (Bit seven of second byte of the block is set if the block is uncorrectable.) 0 = Do not set error flag in packet header. 1 = Bytes output. 0 = Serial output. 1 = 4 VCLK active RDYON. 0 = 1 VCLK active RDYON. See timing diagrams for these output modes for further details. 11 = Data is taken from BYTE[1:0]; I[2:0]; Q[2:0] directly into the deinterleaver on BCLK. Output is available on BCLK. When this mode is selected, set IOCNTRL[4:3]=10. 10 = Data is taken from BYTE[1:0]; I[2:0]; Q[2:0] directly into the deinterleaver on VCLK. Output is available on VCLK. 0x = Data taken from I[2:0] and Q[2:0] into the Viterbi decoder on SCLK. Output is available on VCLK. Set to `1' if deinterleaver is programmed to remove sync bytes. 3.13 NJL: BLOCK LENGTH TIMES INTERLEAVE DEPTH LSB Address: 0x0B; Reset Value = 0x90 BIT 7:0 DESCRIPTION LSByte of BLKLEN x JDEPTH product. 3.14 NJM: BLOCK LENGTH TIMES INTERLEAVE DEPTH MSB Address: 0x0C; Reset Value = 0x09 BIT 7:5 4 3:0 DESCRIPTION Reserved. Set to `0'. Set for deinterleaver to remove the first byte of each block specified by BLKLEN2 register and perform a modified Ramsey II. Most significant nibble of BLKLEN x JDEPTH product. This product must be less than or equal to 2688 decimal. 3.15 BLKLEN2: RS BLOCK LENGTH N Address: 0x0D; BIT 7:0 Reset Value = 0xCC DESCRIPTION Set equal to BLKLEN except when NJM[4] is set. Then use BLKLEN2 = BLKLEN +1. Writing to this register loads the same value into a register in the synchronization (in Viterbi), derandomization and deinterleave modules. Page 12 of 30 A subsidiary of Comtech Telecommunications Corporation PS4210_1099 comtech aha corporation 3.16 JDEPTH: INTERLEAVE DEPTH Address: 0x0E; Reset Value = BIT 7 6 5 4 3:0 0x1C DESCRIPTION Reserved. Set to `0'. A status bit indicating that deinterleaved data is being sent to the Reed-Solomon decoder. This bit is only valid if the deinterleaver is enabled (JDEPTH[4] is a `1'). When a `0' is written to this bit then the current value is not changed. 0 = deinterleaver is not passing data. 1 = deinterleaver is passing data. 0 = Forney, 1 = Ramsey II 1 = Enable, 0 = Bypass Interleave depth. 0 sets depth to 16. 1 is illegal. For more constraints on depth see Functional Description Section. 3.17 RSCONTROL: REED-SOLOMON CONTROL The RS block must be programmed sequentially since there is only one address allocated for it. Address: 0x0F; Reset Value = BIT 0xFF, 0xFF, 0x90, 0xBC, 0xCC, 0x0C DESCRIPTION RES 7:0 Reserved. Set to FF. 7:0 Reserved. Set to FF. RES 7 6:5 4:0 7:0 7:0 7:0 CHKBYTES Reserved. Set to `1'. Reserved. Set to `0'. Number of check bytes, R. Between 0x02 and 0x10. MSGBYTES Number of message bytes in the code, K. Between 0x20 and 0xFD. BLKLEN Number of bytes in a block, N. Between 0x22 and 0xFF. RSCONTROL 0C = Output corrected data. 1C = Pass uncorrected raw data through. PS4210_1099 A subsidiary of Comtech Telecommunications Corporation Page 13 of 30 comtech aha corporation 4.0 SIGNAL DESCRIPTIONS AND SPECIFICATIONS This section describes the signals and each of their characteristics including setup and hold times relative to their synchronization clocks where applicable, reset conditions and load capacitances. 4.1 INPUT SIGNALS SIGNAL RSTN SCLK VCLK BYTE[1:0] I[2:0] Q[2:0] IQSTRB MRDN MWRN MCSN NAME AND DESCRIPTION Reset. When active, forces all internal control circuitry into a known state and initializes all data path elements. Must remain active and remain high as specified in AC Timing before the device can be used. Symbol clock for I and Q. Clock input for Viterbi decoder and for outputs. Byte input. Top two bits of input byte for Byte Input mode bypassing the Viterbi block. When this mode is not used, ground these pins. 3-bit in-phase soft decision input. Soft decision component from demod to the Viterbi decoder. For hard decision input use I[2], I[1:0] are grounded. Used as middle three bits for byte input mode. Synchronized to VCLK in byte input mode, to SCLK for Viterbi. 3-bit quadrature-phase soft decision input. Soft decision component from demod to the Viterbi decoder. For hard decision input use I[2], I[1:0] are grounded. Used as lowest three bits for byte input mode. Synchronized to VCLK in byte input mode; to SCLK for Viterbi. Clock in I, Q and Byte data. When active, inputs Byte, I and Q are strobed into the device. For byte input mode, synchronize to VCLK; to SCLK for Viterbi. For byte input mode, max rate of IQSTRB is 1/8 VCLK or 1 BCLK. Active for one VCLK period. Microprocessor Read Enable. For I2C operation, this must be tied to ground. Microprocessor Write Enable. For I2C operation, this must be tied to ground. Microprocessor Chip Select. For I2C operation, this must be tied high. For parallel 80C188 interface, this signal is low true and Must not Glitch. Microprocessor Address Latch. For I2C operation, this must be tied to ground. I2C Clock. Synchronous clock for I2C interface. For 80C188 interface, SCL this must be tied high. Data Flush. A high signal for a minimum of one VCLK period resets the deinterleaver and initiates a data pipeline flush in Byte Input mode. New DATAFLUSH data must not be input for at least 16 x BLKLEN2 x VCLK periods after the signal goes low. This period is required to flush the data completely through the pipeline. For Viterbi input mode tie to VSS. MAL Page 14 of 30 A subsidiary of Comtech Telecommunications Corporation ACTIVE STATE OR EDGE Low Rising edge Rising edge N/A N/A N/A High Low Low Low High See timing diagram High PS4210_1099 comtech aha corporation 4.2 OUTPUT SIGNALS SIGNAL DO[7:0] BLKNEW RDYON BLKERR READY BCLK 4.3 NAME AND DESCRIPTION ACTIVE STATE OR EDGE Data Output Bus. The output byte is driven from the rising edge of VCLK or BCLK. For serial output mode, DO[7] contains the data and N/A DO[6:0] is `0'. Start of block signal. MPEG-II transport stream packet start flag. Valid High with RDYON low during the first byte of each block. Output Ready strobe. Indicates that output data on DO[7:0] is valid. There is no external signal to throttle output data transfer. The max rate Low of RDYON is 1/8 VCLK or BCLK. Block uncorrectable. Active during first output byte of packet (with RDYON low and BLKNEW high) if the block to be output cannot be High corrected. Should be ignored if Reed-Solomon block is bypassed. Microprocessor Access Ready. Indicates that the chip has completed a microprocessor read or write cycle. At the beginning of processor cycles, Low when busy, this output is driven to a low voltage, indicating that the chip is not ready. Otherwise, This signal is tristated when processor cycles are inactive. The reset state tristated. of this pin is high impedance. Output Clock. This clock is derived from VCLK and is 1/8 frequency of VCLK. BIDIRECTIONAL SIGNALS SIGNAL MD[7:0] SDA PS4210_1099 NAME AND DESCRIPTION Multiplexed Address/Data Bus. Mux bus supporting 80C188. For I2C interface, MD[4:0] specify the top five bits of address for the device while MD[7:5] are don't cares and must be terminated high or low. I2C Data Bus. Serial data for I2C interface. For 80C188, this must be tied high. A subsidiary of Comtech Telecommunications Corporation ACTIVE STATE OR EDGE N/A N/A Page 15 of 30 comtech aha corporation 4.4 4.5 INPUT SPECIFICATIONS PIN NUMBER SIGNAL NAME SELF LOAD (MAX IN pF) 31 30 28 25 24 23 37 38 48 26 45 46 41 43 21 34 39 19 18 I[2] I[1] I[0] Q[2] Q[1] Q[0] BYTE[1] BYTE[0] RSTN IQSTRB MRDN MWRN MCSN MAL SCLK VCLK SCL Reserved, connect to VSS DATAFLUSH 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 STROBE VCLK/SCLK VCLK/SCLK VCLK/SCLK VCLK/SCLK VCLK/SCLK VCLK/SCLK VCLK VCLK VCLK VCLK/SCLK See timing diagram N/A N/A VCLK N/A VCLK OUTPUT SPECIFICATIONS Page 16 of 30 PIN NUMBER SIGNAL NAME LOAD CAP (MAX IN pF) STROBE REF 9 8 6 4 3 1 67 66 12 11 13 51 16 14 DO[7] DO[6] DO[5] DO[4] DO[3] DO[2] DO[1] DO[0] RDYON BLKNEW BLKERR READY BCLK Reserved 20 20 20 20 20 20 20 20 20 20 20 20 20 N/A VCLK VCLK VCLK VCLK VCLK VCLK VCLK VCLK VCLK VCLK VCLK VCLK VCLK N/A A subsidiary of Comtech Telecommunications Corporation PS4210_1099 comtech aha corporation 4.6 4.7 BIDIRECTIONAL PIN SPECIFICATIONS PIN NUMBER SIGNAL NAME SELF LOAD (MAX IN pF) LOAD CAP (MAX IN pF) 50 52 54 56 57 59 61 62 64 SDA MD[0] MD[1] MD[2] MD[3] MD[4] MD[5] MD[6] MD[7] 10 10 10 10 10 10 10 10 10 20 20 20 20 20 20 20 20 20 VCLK See timing diagrams POWER & GROUND PINS PIN NUMBER SIGNAL NAME 2, 7, 17, 22, 29, 35, 36, 42, 49, 55, 60, 65 5, 10, 15, 20, 27, 32, 33, 40, 44, 47, 53, 58, 63, 68 VDD VSS PINOUT 9 8 7 6 5 4 3 2 1 68 67 66 65 64 63 62 61 DO7 DO6 VDD DO5 VSS DO4 DO3 VDD DO2 VSS DO1 DO0 VDD MD7 VSS MD6 MD5 4.8 STROBE REF 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 AHA4210A-062 PJC 60 59 58 57 56 55 54 53 52 51 50 49 48 47 46 45 44 VDD MD4 VSS MD3 MD2 VDD MD1 VSS MD0 READY SDA VDD RSTN VSS MWRN MRDN VSS VSS I0 VDD I1 I2 VSS VSS VCLK VDD VDD BYTE1 BYTE0 SCL VSS MCSN VDD MAL 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 VSS BLKNEW RDYON BLKERR RESERVED VSS BCLK VDD DATAFLUSH RESERVED VSS SCLK VDD Q0 Q1 Q2 IQSTRB Reserved Pins: Leave pin 14 No Connect Tie pin 19 to VSS PS4210_1099 A subsidiary of Comtech Telecommunications Corporation Page 17 of 30 comtech aha corporation 5.0 TIMING Unless otherwise specified, all timing references from clock edges are referred to the crossover-tocrossover point of SCLK and VCLK at 1.4 Volts. Figure 6: Clock Timing - SCLK and VCLK 2.0 CLK 1.4 0.8 2 3 4 5 1 NUMBER 1 1 1 1 2 3 4 5 PARAMETER VCLK period VCLK period VCLK period SCLK period CLK rise time CLK fall time CLK high pulsewidth CLK low pulsewidth MIN MAX 16.13 16.13 16.13 16.13 100 400 UNITS NOTES nsec nsec nsec nsec nsec nsec nsec nsec 1 2 3 UNITS NOTES VCLK clocks nsec VCLK clocks 1 2 2 2 6.4 7.7 4 4 Notes: 1) In 80C188 mode. 2) In fast I2C mode. 3) In standard I2C mode. 4) Based on design goals. Figure 7: Reset Timing 1 3 VCLK 2 2 RSTN IQSTRB NUMBER 1 2 3 PARAMETER RSTN low pulsewidth RSTN setup to VCLK Internal initialization time MIN MAX 20 5 28 Notes: 1) The RSTN signal can be asynchronous to the VCLK signal. It is internally synchronized to the rising edge of VCLK. 2) Interaction with the chip can occur after this period. 3) Hold IQSTRB low until all registers are programmed. Page 18 of 30 A subsidiary of Comtech Telecommunications Corporation PS4210_1099 comtech aha corporation Figure 8: DATAFLUSH Timing - Byte Input Mode VCLK 1 DATAFLUSH 2 3 NUMBER 1 2 3 PARAMETER MIN DATAFLUSH setup DATAFLUSH hold DATAFLUSH pulsewidth MAX UNITS 5 5 1 NOTES nsec nsec VCLK Notes: 1) DATAFLUSH function requires (16xBLKLEN2) VCLKs after the DATAFLUSH pulse. Figure 9: Microprocessor Write Timing VCLK 1 MCSN 2 3 MAL 4 3 MWRN READY tristate 6 5 8 MD[7:0] tristate 9 10 11 Address1 Data NUMBER PARAMETER MIN 1 2 3 4 5 6 7 8 9 10 11 MCSN hold from MWRN deasserted MAL pulsewidth MCSN low and MAL low to MWRN low MWRN pulsewidth MCSN low to READY low MWRN low to READY deasserted READY deasserted to MWRN high Address setup to MAL Address hold from MAL MWRN low to data valid DATA hold 0 16 0 14 PS4210_1099 7 tristate 12 0 10 5 MAX 22 14 6 0 A subsidiary of Comtech Telecommunications Corporation UNITS NOTES nsec nsec nsec VCLK clocks nsec VCLK clocks nsec nsec nsec VCLK clocks nsec Page 19 of 30 comtech aha corporation Figure 10: Microprocessor Read Timing VCLK 1 MCSN 2 3 MAL 4 3 MRDN 6 READY tristate 7 5 8 MD[7:0] tristate 9 Address1 tristate Data 10 11 12 NUMBER PARAMETER MIN 1 2 3 4 5 6 7 8 9 10 11 12 MCSN hold from MRDN deasserted MAL pulsewidth MCSN low and MAL low to MRDN low MRDN pulsewidth MCSN low to READY low MRDN low to READY deasserted READY deasserted to MRDN high Address setup to MAL fall Address hold from MAL fall MRDN low to data driven MRDN deassert to data released MRDN low to data valid 0 16 0 12 Page 20 of 30 tristate MAX 22 12 0 10 5 0 0 7 A subsidiary of Comtech Telecommunications Corporation UNITS NOTES nsec nsec nsec VCLK clocks nsec VCLK clocks nsec nsec nsec nsec nsec VCLK clocks PS4210_1099 comtech aha corporation 2 Figure 11: I C Interface Timing SDA 1 3 9 8 SCL 2 STOP NUMBER 1 2 3 4 5 6 7 8 9 10 6 4 5 7 START 10 START PARAMETER SCL Clock frequency Bus free time between a STOP and START condition Hold time (repeated) START condition. After this period, the first clock pulse is generated Low period of the SCL clock High period of the SCL clock Setup time for a repeated START Data hold time Data setup time Rise time of both SDA and SCL Fall time of both SDA and SCL Setup time for STOP condition STANDARD MODE(1) MIN MAX STOP HIGH SPEED(1) MIN MAX UNIT 400 KHz 100 4.7 1.3 sec 4 0.6 sec 4.7 4.0 4.7 0(2) 250 1.3 0.6 0.6 0(2) 100(4) sec sec sec sec nsec nsec nsec sec 250 250 4.0 0.9(3) 250 250 0.6 Notes: 1) All I2C Interface timings are based on design goals. 2) A device must internally provide a hold time of at least 300 nsec for the SDA signal in order to bridge the undefined region of the falling edge of SCL. 3) The maximum data hold time, 6, has only to be met if the device does not stretch the low period, 7, of the SCL signal. 4) A fast mode I2C bus device can be used in a standard mode I2C bus system, but the requirement for data setup time 250 nsec must then be met. This will automatically be the case if the device does not stretch the low period of the SCL signal. If such a device does stretch the low period of the signal, it must output the next data bit to the SDA line tR max + tSU:DAT = 1000 + 250 +1250 nsec (according to the standard mode I2C bus specification) before the SCL line is released. PS4210_1099 A subsidiary of Comtech Telecommunications Corporation Page 21 of 30 comtech aha corporation Figure 12: Input - Serial Mode: IOCNTRL[2:1] = 0x Mode SCLK I+Q IQSTRB 1 3 NUMBER 1 2 3 4 Note: PARAMETER 2 4 MIN IQSTRB setup to SCLK IQSTRB hold from SCLK IQ setup to SCLK IQ hold from SCLK MAX 5 1 5 1 UNITS NOTES nsec nsec nsec nsec I and Q signals may be strobed once per SCLK and IQSTRB may be held high. The timing diagram above illustrates I and Q data on every other SCLK. Figure 13: Input - Byte Mode: IOCNTRL[2:1] = 10 Mode VCLK 1 2 IQSTRB 3 BYTE, I, Q 4 5 NUMBER 1 2 3 4 5 Page 22 of 30 PARAMETER IQSTRB setup to VCLK IQSTRB hold from VCLK Byte, I and Q setup to VCLK Byte, I and Q hold from VCLK IQSTRB period MIN MAX 5 3 5 3 8 A subsidiary of Comtech Telecommunications Corporation UNITS NOTES nsec nsec nsec nsec VCLK clocks PS4210_1099 comtech aha corporation Figure 14: Input - Byte Mode IOCNTRL[2:1] = 11 VCLK 1 1 BCLK 2 3 IQSTRB 4 5 BYTE, I, Q NUMBER 1 2 3 4 5 PARAMETER BCLK delay from VCLK IQSTRB setup to VCLK IQSTRB hold to VCLK Byte, I and Q setup to VCLK Byte, I and Q hold to VCLK MIN MAX UNITS NOTES 11 nsec nsec nsec nsec nsec 1 1 1 1 5 3 5 3 Note: 1) Data and IQSTRB are latched on the rising edge of VCLK when BCLK is low and IQSTRB is high. PS4210_1099 A subsidiary of Comtech Telecommunications Corporation Page 23 of 30 comtech aha corporation Figure 15: Output - BCLK Mode: IOCNTRL[4:3] = 10, [2:1] = 11 VCLK 1 1 BCLK 2 DO[7:0] RDYON BLKNEW BLKERR 2 Figure 16: Output - Byte Mode: IOCNTRL[4:3] = 10, IOCNTRL[2:1] 11 VCLK 2 3 4 RDYON 2 DO[7:0] 2 BLKNEW BLKERR Note: 2 RDYON remains asserted for one clock period. Output data stays asserted for eight clocks minimum. NUMBER 1 2 3 4 PARAMETER BCLK delay from VCLK DO [7:0], RDYON, BLKNEW and BLKERR from VCLK RDYON output hold RDYON deassert time MIN MAX UNITS 11 nsec 11 nsec 1 7 NOTES nsec VCLK clocks Timing diagrams 15 through 18 show first two bytes of a block with uncorrectable errors for various RDYON modes. Page 24 of 30 A subsidiary of Comtech Telecommunications Corporation PS4210_1099 comtech aha corporation Figure 17: IOCNTRL[4:3] = 00, Serial Output 0 1 2 3 4 5 6 7 VCLK RDYON DO[7] 7 6 5 4 3 2 1 0 7 6 5 4 3 2 0 7 6 5 4 3 2 BLKERR BLKNEW Figure 18: IOCNTRL[4:3] = 01, Serial Output 0 1 2 3 4 5 6 7 VCLK RDYON DO[7] 7 6 5 4 3 2 1 BLKERR BLKNEW Figure 19: IOCNTRL[4:3] = 10, Byte Output 0 1 2 3 4 5 6 7 VCLK RDYON DO[7:0] 8 bits of data 8 bits of data BLKERR BLKNEW Figure 20: IOCNTRL[4:3] = 11, Byte Output 0 1 2 3 4 5 6 7 VCLK RDYON DO[7:0] 8 bits of data 8 bits of data BLKERR BLKNEW PS4210_1099 A subsidiary of Comtech Telecommunications Corporation Page 25 of 30 comtech aha corporation 6.0 DC ELECTRICAL CHARACTERISTICS SYMBOL ABSOLUTE MAXIMUM STRESS RATINGS CHARACTERISTICS MIN MAX UNITS Tstg Storage temperature Vdd Supply voltage Vin Input voltage Package: 68 pin PLCC SYMBOL -55 -0.5 Vss-0.5 150 6.0 Vdd+0.5 C V V OPERATING CONDITIONS CHARACTERISTICS MIN MAX UNITS Vdd Idd Supply voltage Supply current Idd 5.25 1 V mA Supply current 360 mA Idd Supply current 240 mA Ta Ambient temperature 70 C Note 1: SYMBOL Vih Vil Vil Iil Cin SYMBOL 4.75 0 CHARACTERISTICS Input high voltage Input low voltage Input low voltage for VCLK Input leakage Self load capacitance CHARACTERISTICS INPUTS MIN 2.0 Vss Vss -10 MAX UNITS Vdd 0.8 0.6 10 10 V V V A pF OUTPUTS MIN MAX Static - clocks stopped @43 MHz; Dynamic; modes 1 and 3 at 5.25V; Figure 21 @62 MHz; Dynamic; modes 2, 4 and 5 at 5.25V. Note 1 Figure 22 2.4 Vss -4 TEST CONDITIONS All signals except VCLK 0<Vin<Vdd UNITS TEST CONDITIONS 4 V V mA mA Ioh=4mA Iol=4mA Voh=2.4V Vol=0.4 0<Vout<Vdd bidirectionals only Output high voltage Output low voltage Output high current Output low current Ioz High Impedance leakage 10 A Self load capacitance Load capacitance 10 20 pF pF Page 26 of 30 TEST CONDITIONS Modes 2, 4 and 5 data are based on design goals and charaterization of sample devices, not production tested. Voh Vol Ioh Iol Cout Cl TEST CONDITIONS Vdd 0.4 A subsidiary of Comtech Telecommunications Corporation PS4210_1099 comtech aha corporation Figure 21: Power vs. VCLK Rate, Estimated for Modes 1 and 3 500.0 I (mA @ 5.25v) 400.0 300.0 200.0 100.0 0.0 0.0 10.0 20.0 30.0 40.0 VCLK Frequency 50.0 60.0 70.0 Figure 22: Max Ambient Temperature (Ta) vs. VCLK Rate, Estimated for Modes 1 and 3 Air Flow = 225 LFPM 80.0 Ambient Temperature 75.0 70.0 65.0 60.0 55.0 50.0 0.0 Note: 10.0 20.0 30.0 40.0 VCLK Frequency 50.0 60.0 70.0 Curves represent 68 pin PLCC. For other packaging options, please contact AHA. PS4210_1099 A subsidiary of Comtech Telecommunications Corporation Page 27 of 30 comtech aha corporation 7.0 PACKAGING PLCC Dimensions Inches (Millimeters) A .050 (1.27) B min/max C min/max .985/.995 .950/.956 (25.02/25.27) (24.13/24.28) D min/max E min F G .165/.200 (4.19/5.08) .020 (0.51) .002 (0.051) .0035 (0.089) Packaging Pin 1 Identification AHA4210A-062 PJC C B YYWWD-(COUNTRY OF ORIGIN) LLLLL A D E F = Lead Planarity Note: G = Lead Skew YYWWD = Data Code LLLLL = Lot Number Complete Package Drawing Available Upon Request Page 28 of 30 A subsidiary of Comtech Telecommunications Corporation PS4210_1099 comtech aha corporation 8.0 ORDERING INFORMATION 8.1 AVAILABLE PARTS PART NUMBER AHA4210A-062 PJC 8.2 DESCRIPTION Viterbi with Reed-Solomon Decoder PART NUMBERING AHA 4210 A- 062 P J C Manufacturer Device Number Revision Level Speed Designation Package Material Package Type Test Specification Device Number: 4210 Revision Letter: A Package Material Codes: P Plastic Package Type Codes: J J - Leaded Chip Carrier Test Specifications: C Commercial 0C to +70C 9.0 AHA RELATED TECHNICAL PUBLICATIONS DOCUMENT # ABRS05 ABSTD1 ANRS01 ANRS02 ANRS06 ANRS07 ANRS08 ANRS09 ANRS10 FECESW GLGEN1 IEEEART PS4210_1099 DESCRIPTION AHA Application Brief - Programming the AHA4210 for Non-DVB/DAVIC Applications AHA Application Brief - Data Compression and Forward Error Correction Standards AHA Application Note - Primer: Reed-Solomon Error Correction Codes (ECC) AHA Application Note - Reed-Solomon Interleaving for Burst Error Correction AHA Application Note - Code Performance, Error Rate Monitoring and Processing Delays Through the AHA4210 AHA Application Note - Soft Decision Thresholds and Effects on Viterbi Performance AHA Application Note - AHA4210 RSVP Synchronization Performance AHA Application Note - Frequently Asked Questions and Answers about the AHA4210 RSVP AHA Application Note - AHA4210 Viterbi Decoder Low Code Rate Noise Floor Concatenated FEC Encoder Software (RSVP) General Glossary of Terms Greg Zweigle, TJ Berge, Paul Winterrowd and Aziz Makhani, "A Viterbi, Convolutional Interleave, and Reed-Solomon Decoder IC," IEEE 1995 International Conference on Consumer Electronics A subsidiary of Comtech Telecommunications Corporation Page 29 of 30 comtech aha corporation 10.0 OTHER TECHNICAL PUBLICATIONS DOCUMENT J.L. Ramsey, "Realization of Optimal Interleavers," IEEE Transaction on Information Theory, May 1970, pp. 338-345 Philips/Signetics, "The I2C Bus and How to Use It," January 1992 Philips, "Specification IIC bus." TVE 80134 Digital Video Broadcasting, DT/8622/DVB, "Implementation Guidelines for the use of MPEG-II Systems, Video and Audio in Satellite and Cable Broadcasting Applications in Europe," May 26, 1994 Digital Video Broadcasting, DT/8610/III-B, "User Requirements for Digital Broadcasting Systems by Satellite and Cable," May 2, 1994 Page 30 of 30 A subsidiary of Comtech Telecommunications Corporation PS4210_1099