Low Latency Ethernet 10G MAC Intel® FPGA IP User Guide

ID 683426
Date 3/01/2022
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4.5.5.1. Frame Length

The frame length must be at least 64 (0x40) bytes and not exceed the following maximum value for the different frame types:

  • Basic—The value in the rx_frame_maxlength register.
  • VLAN tagged—The value in the rx_frame_maxlength register plus four bytes when the rx_vlan_detection[0] register bit is 0; or the value in the rx_frame_maxlength register when the rx_vlan_detection[0] register bit is set to 1.
  • Stacked VLAN tagged—The value in the rx_frame_maxlength register plus eight bytes when the rx_vlan_detection[0] register bit is 0; or the value in the rx_frame_maxlength register when the rx_vlan_detection[0] register bit is set to 1.

The following error bits represent frame length violations:

  • avalon_st_rx_error[2]—undersized frames.
  • avalon_st_rx_error[3]—oversized frames.