F-Tile Ethernet Intel® FPGA Hard IP User Guide

ID 683023
Date 4/01/2024
Document Table of Contents Conditions Triggering XON Frame Transmission

The TX MAC transmits PAUSE or PFC XON frames when one of the following conditions occurs:

  • Client requests XON transmission—A client can explicitly request that XON frames be sent using the pause control interface signal. When i_tx_pause is deasserted, a PAUSE XON frame is sent to the Ethernet network when the current frame transmission completes. Similarly, when i_tx_pfc[n] is deasserted, a PFC frame is sent with a PFC XON message for queue n. If multiple PFC queues are deasserted, the TX MAC will pack the requests into the same PFC packet if possible.
  • Host (software) requests XON transmission—Resetting the pause request register triggers a request that an XON frame be sent.