[AHA]

INTRODUCTION
The AHA4013B is a single chip integrated circuit that implements a high speed Reed-Solomon Forward Error Correction algorithm. The AHA4013B is a member of the AHA PerFEC family of high speed forward error correction (FEC) devices conforming to the Intelsat IESS-308 specification.

FEATURES
HIGH PERFORMANCE
• Polynomial complies to Intelsat IESS-308; RTCA DO-217 Appendix F, Revision D and proposed ITU-TS SG-18 (Formerly CCITT SG-18) standards
• 50 MBytes/sec burst transfer rate with a 50 MHz clock for all block lengths
• Sustained data transfer rate of 12.5 MBytes/sec for block lengths from 54 bytes through 255 bytes using a 50 MHz clock
• Processing latency time less than 12.2 µsec in continuous operation for block lengths of 100 bytes

FLEXIBILITY
• Programmable to correct from 1 to 10 error bytes or 20 erasure bytes per block
• Block lengths programmable from 3 to 255 bytes
• Encode, decode or pass-through capability in line with data flow
• Outputs corrected data or correction vectors in forward or reverse order
• Continuous or burst data transfer
• Programmable error threshold to help determine channel performance

SYSTEM INTERFACE
• Byte wide synchronous I/O ports with internal buffering on both ports
• Dedicated control pins permit discontinuities in system data flow

OTHERS
• 44 pin PLCC; 50 mil lead pitch
• Pin compatible with lower performance AHA4011/12
• Plug compatible with AHA4011/12 except for an initialization register setting
• Software emulation of the algorithm available