F-Tile Triple-Speed Ethernet Intel® FPGA IP User Guide

ID 741328
Date 4/03/2023
Public

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Document Table of Contents

5.1.4.5. Payload Pad Removal

You can turn on padding removal by setting the PAD_EN bit in the command_config register to 1. The MAC function removes the padding, prior to forwarding the frames to the user application, when the payload length is less than the following values for the different frame types:
  • 46 bytes for basic MAC frames
  • 42 bytes for VLAN tagged frames
  • 38 bytes for stacked VLAN tagged frames
Padding removal is not applicable when:
  • the length or type field is equal to or greater than 1536 (0x600) for basic frame.
  • the client length or type field is equal to or greater than 1536 (0x600) for VLAN and stacked VLAN frames.

When padding removal is turned off, complete frames including the padding are forwarded to the Avalon® streaming receive interface.