CRC Generation and Check

At the TX channel, the core automatically generates CRC octets, appends them to the end of the frame, and transmits to the XGMII TX interface.

At the RX channel, the core decodes the Ethernet frames and checks against 4 CRC octets that are trailing at the Ethernet frame. At the RX AXI ST interface, the CRC octets are forwarded to the RX_AXI_TDATA ports. The CRC forwarding is illustrated in Figure 1.

The CRC polynomial that is used in core is x³² + x²⁶ + x²³ + x²² + x¹⁶ + x¹² + x¹¹ + x¹⁰ + x⁸ + x⁷ + x⁵ + x⁴ + x² + x + 1.