In 100G mode, the bit ordering for the input of FEC0 decoder is as follows:
- At the start of the codeword where
rx_fec0_slice0_din_start=1
,-
rx_serdes_data0[79:0]=CW[79:0]
-
rx_serdes_data1[79:0]=CW[159:80]
-
rx_serdes_data2[79:0]=CW[239:160]
-
rx_serdes_data3[79:0]=CW[319:240]
-
- At the second codeword cycle,
-
rx_serdes_data0[79:0]=CW[399:320]
-
rx_serdes_data1[79:0]=CW[479:400]
-
rx_serdes_data2[79:0]=CW[559:480]
-
rx_serdes_data3[79:0]=CW[639:560]
-
- At the third codeword cycle,
-
rx_serdes_data0[79:0]=CW[719:640]
-
rx_serdes_data1[79:0]=CW[799:720]
-
rx_serdes_data2[79:0]=CW[879:800]
-
rx_serdes_data3[79:0]=CW[959:880]
-
- At the 17th codeword cycle,
-
rx_serdes_data0[79:0]=CW[5199:5120]
-
rx_serdes_data1[79:0]=CW[5279:5200]
-
rx_serdes_data2[79:0]=CW[5359:5280]
-
rx_serdes_data3[79:0]=CW[5439:5360]
-
In 100G mode, the bit ordering for the output of FEC0 decoder is as follows:
- At the start of the codeword where rx_fec0_slice0_dout_start=1,
-
rx_fec0_slice0_dout[159:0]=CW[159:0]
-
rx_fec0_slice1_dout[159:0]=CW[319:160]
-
- At the second codeword cycle,
-
rx_fec0_slice0_dout[159:0]=CW[479:320]
-
rx_fec0_slice1_dout[159:0]=CW[639:480]
-
- At the third codeword cycle,
-
rx_fec0_slice0_dout[159:0]=CW[799:640]
-
rx_fec0_slice1_dout[159:0]=CW[959:800]
-
- At the 17th codeword cycle,
-
rx_fec0_slice0_dout[159:0]=CW[5279:5120]
-
rx_fec0_slice1_dout[159:0]=CW[5439:5280]
-
The bit ordering for all 100G decoder interfaces is similar to FEC0. See the following table for a summary of 100G decoder bit ordering.
FEC Inst | Decoder Input | Input CW Start Position | Decoder Output | Output CW Start Position |
---|---|---|---|---|
FEC0 | rx_serdes_data0[79:0] rx_serdes_data1[79:0] rx_serdes_data2[79:0] rx_serdes_data3[79:0] |
rx_serdes_data0[0] | rx_fec0_slice0_dout[159:0] rx_fec0_slice1_dout[159:0] |
rx_fec0_slice0_dout[0] |
FEC1 | rx_serdes_data4[79:0] rx_serdes_data5[79:0] rx_serdes_data6[79:0] rx_serdes_data7[79:0] |
rx_serdes_data4[0] | rx_fec1_slice0_dout[159:0] rx_fec1_slice1_dout[159:0] |
rx_fec1_slice0_dout[0] |
FEC2 | rx_serdes_data8[79:0] rx_serdes_data9[79:0] rx_serdes_data10[79:0] rx_serdes_data11[79:0] |
rx_serdes_data8[0] | rx_fec2_slice0_dout[159:0] rx_fec2_slice1_dout[159:0] |
rx_fec2_slice0_dout[0] |
FEC3 | rx_serdes_data12[79:0] rx_serdes_data13[79:0] rx_serdes_data14[79:0] rx_serdes_data15[79:0] |
rx_serdes_data12[0] | rx_fec3_slice0_dout[159:0] rx_fec3_slice1_dout[159:0] |
rx_fec3_slice0_dout[0] |
FEC4 | rx_serdes_data16[79:0] rx_serdes_data17[79:0] rx_serdes_data18[79:0] rx_serdes_data19[79:0] |
rx_serdes_data16[0] | rx_fec4_slice0_dout[159:0] rx_fec4_slice1_dout[159:0] |
rx_fec4_slice0_dout[0] |
FEC5 | rx_serdes_data20[79:0] rx_serdes_data21[79:0] rx_serdes_data22[79:0] rx_serdes_data23[79:0] |
rx_serdes_data20[0] | rx_fec5_slice0_dout[159:0] rx_fec5_slice1_dout[159:0] |
rx_fec5_slice0_dout[0] |