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

4.2.4. Frame Check Sequence (CRC-32) Insertion

The TX MAC computes and inserts a CRC32 checksum in the transmitted MAC frame. The frame check sequence (FCS) field contains a 32-bit CRC value. The MAC computes the CRC32 over the frame bytes that include the source address, destination address, length, data, and pad (if applicable). The CRC checksum computation excludes the preamble, SFD, and FCS. The encoding is defined by the following generating polynomial:

FCS(X) = X32 +X26 +X23 +X22 +X16 +X12 +X11 +X10 +X8 +X7 +X5 +X4 +X2 +X1 +1

CRC bits are transmitted with MSB (X32) first.

If you configure your Low Latency 100G Ethernet Intel FPGA IP core with no flow control, you can configure your IP core TX MAC to implement TX CRC insertion or not, by turning Enable TX CRC insertion on or off in the Low Latency 100G Ethernet Intel FPGA parameter editor. By default, the CRC insertion feature is enabled.