Low Latency 100G Ethernet Intel® FPGA IP Core User Guide: For Stratix® 10 Devices

ID 683100
Date 8/05/2024
Public
Document Table of Contents

7.6. TX Reed-Solomon FEC Registers

Table 30.  TX Reed-Solomon FEC Registers
Addr Name Bit Description Reset Access
0xC00 REVID [31:0] Reed-Solomon FEC TX module revision ID. 0x0809 2017 RO
0xC01 TX_RSFEC_SCRATCH [31:0] Scratch register available for testing. 32'b0 RW
0xC02 TX_RSFEC_NAME_0 [31:0] Final 4 characters of IP core variation identifier string, "100gRSFECoTX". 0x436F 5458 RO
0xC03 TX_RSFEC_NAME_1 [31:0] Middle 4 characters of IP core variation identifier string, "100gRSFECoTX". 0x5253 4645 RO
0xC04 TX_RSFEC_NAME_2 [31:0] Initial 4 characters of IP core variation identifier string, "100gRSFECoTX". 0x3130 3067 RO
0xC05 ERR_INS_EN [31:5] Reserved. 0x00000000 RW
[4] When 1'b1, enables error insertion for single FEC codeword. This bit self-clears after the Reed-Solomon FEC transmitter inserts the error.
[3:1] Reserved.
[0] When 1'b1, enables error insertion for every FEC codeword. Specifies that the Reed-Solomon FEC transmitter should insert the error in every FEC codeword.
0xC06 ERR_MASK [31:25] Reserved. 0x00000000 RW
[24] SYM_32: Each FEC codeword consists of 16 groups of 33 symbols. This register field specifies whether the RS-FEC transmitter corrupts symbol 32 (of symbols 0-32) in each corrupted group. Specifically, the value of 1 directs the IP core to corrupt symbol 32 according to BIT_MASK.
[23:18] Reserved.
[17:8] BIT_MASK: Specifies which of the ten bits the RS-FEC transmitter corrupts in each corrupted symbol. Specifically, the value of 1 in bit [n+8] directs the IP core to corrupt bit [n] in each corrupted symbol.
[7:4] Reserved.
[3:0] GROUP_NUM: Each FEC codeword consists of 16 groups of 33 symbols. This register field specifies the single group of 33 symbols that the RS-FEC transmitter corrupts in the current FEC codeword.

The following values are defined:

  • 4'b000: First group of 33 symbols (symbols 0-32)
  • 4'b0001: Second group of symbols (symbols 33-65)
  • ...
  • 4'b1110: Second-to-final group of symbols (symbols 462-494)
  • 4'b1111: Final group of symbols (symbols 495-527, or {chk[13:0],sym[514:495]})
Continuous corruption of groups 0-3 might lead to strange behavior as a result of alignment marker corruption.
0xC07 SYMBOL_ERR_MASK [31:0] Each FEC codeword consists of 16 groups of 33 symbols. This register specifies which of the lower order 32 symbols in a group the RS-FEC transmitter corrupts. Specifically the value of 1 in bit [n] directs the IP core to corrupt symbol n. 32'b0 RW