PS4210-1099 Page 1 of 30
Advanced Hardware Architectures, Inc.
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
deinter leav er . Th e de vice conforms to the MPEG- II
transport layer protocol spe cified 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
ex t er nal ly. Each functiona l block may be bypas sed
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 docume nt cont ai ns k ey features,
correction terms, functional description, signal
functions, Related Technical Publications, DC and
AC characteristics, pinout, package dimension and
ordering information.
1.1 APPLICATIONS
• Satelli te communications/VSAT
• DBS
• Military Communications
1.2 FEATURES
GENERAL:
• Conforms t o t he 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 err or rate monitor
• Programmable bypass modes for each of the
major b locks
• Configured to DVB mode of operation on
power-up
• 68 pin P LCC
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
• Intern al 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 log ically 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 b etween the numbers . Most si gnif i cant b it
is always shown first, followed by least
significant bit. For example, ERRSTAT[ 6:0]
represents number of bytes corrected by the
Reed-Solomon decoder.
- A product of two variables is expressed with an
“x”, for example, BLKLEN2 x JDEPTH
represe nts Block Length mu ltip lied b y Int erle a ve
Depth.
- Megabytes per second is referred to as MBytes/
sec or MB/se c. Megabit s per second i s 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.