Table 67: RX FEC Attributes (cont'd)
Attribute Type Description
FEC_RX1_BYPASS_CORRECTION [1] FEC RX slice 1 error correction select:
1’b0: Error correct enabled.
1’b1: Error correct disabled.
FEC_RX0_BYPASS_INDICATION [2] FEC RX slice 0 error indicator enable:
1’b0: Error indicator enabled.
1’b1: Error indicator disabled.
FEC_RX1_BYPASS_INDICATION [3] FEC RX slice 1 error indicator enable:
1’b0: Error indicator enabled.
1’b1: Error indicator disabled.
FEC_CFG1[15:0] (FEC_RX0_VL_LENGTH[15:0])
FEC_CFG3[4] (FEC_RX0_VL_LENGTH[16])
17-bit Binary Frame length (in 66-bit blocks per PCS lane)
for FEC RX slice 0. Ignored if FEC RX slice 0 is
configured in raw FEC mode.
FEC_CFG2[15:0] (FEC_RX1_VL_LENGTH[15:0])
FEC_CFG3[5] (FEC_RX1_VL_LENGTH[16])
17-bit Binary Frame length (in 66-bit blocks per PCS lane)
for FEC RX slice 1. Ignored if FEC RX slice 1 is
configured in raw FEC mode.
FEC_CFG4[15:0] (FEC_RX_VL_MARKER_ID0[15:0])
FEC_CFG5[15:0] (FEC_RX_VL_MARKER_ID0[31:16])
FEC_CFG6[15:0] (FEC_RX_VL_MARKER_ID0[47:32])
FEC_CFG7[15:0] (FEC_RX_VL_MARKER_ID0[63:48])
64-bit Binary Alignment marker 0 (common), for 50GE
operation on FEC RX slice 0, and for 100GE,
FlexO, and Interlaken operation on FEC RX
slices 0–1.
FEC_CFG8[15:0] (FEC_RX_VL_MARKER_ID1[15:0])
FEC_CFG9[15:0] (FEC_RX_VL_MARKER_ID1[31:16])
FEC_CFG10[15:0]
(FEC_RX_VL_MARKER_ID1[47:32])
FEC_CFG11[15:0]
(FEC_RX_VL_MARKER_ID1[63:48])
64-bit Binary
Alignment marker 0 (common) for 50GE
operation on FEC RX slice 1. Ignored if FEC
RX slice 0 is configured in 100G mode.
FEC_CFG12[15:0] (FEC_RX_VL_MARKER_ID4[15:0])
FEC_CFG13[15:0]
(FEC_RX_VL_MARKER_ID4[31:16])
FEC_CFG14[15:0]
(FEC_RX_VL_MARKER_ID4[47:32])
FEC_CFG15[15:0]
(FEC_RX_VL_MARKER_ID4[63:48])
64-bit Binary
Alignment marker 4 (lane-specific) for
100GE, FlexO, and Interlaken operation on
FEC RX slice 0–1. Alignment marker 2 (lane-
specific) for 50GE operation on FEC RX slice
0.
FEC_CFG16[15:0] (FEC_RX_VL_MARKER_ID5[15:0])
FEC_CFG17[15:0]
(FEC_RX_VL_MARKER_ID5[31:16])
FEC_CFG18[15:0]
(FEC_RX_VL_MARKER_ID5[47:32])
FEC_CFG19[15:0]
(FEC_RX_VL_MARKER_ID5[63:48])
64-bit Binary
Alignment marker 5 (lane-specific) for
100GE, FlexO, and Interlaken operation on
FEC RX slice 0–1.
RS-FEC Sub-Modes
There are three sub-modes of RS-FEC decoder operaon dened by the IEEE 802.3bj
specicaon. The primary purpose of the dierent sub-modes is to allow latency to be reduced
in cases where the line BER is low enough that full error correcon is not required. The following
table lists the valid RS-FEC operang sub-modes. When congured in 2x50G FEC mode, the sub-
mode can be set independently for each slice.
Chapter 4: Receiver
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