Low Latency Ethernet 10G MAC IP User Guide: Agilex™ 3 and Agilex™ 5 FPGAs and SoCs

ID 813663
Date 9/01/2025
Public
Document Table of Contents

5.2. Speed Selection Signal

Table 16.  Speed Selection Signal
Signal Operating Mode Direction Width Description
speed_sel 10G, 1G/10G,10M/100M/1G/10G In 2

Connect this asynchronous signal to the PHY to obtain the PHY's speed:

  • 0x0 = 10 Gbps
  • 0x1 = 1 Gbps
  • 0x2 = 100 Mbps
  • 0x3 = 10 Mbps
  • 0x4 = 2.5 Gbps
  • 0x5 = 5 Gbps

The speed_sel signal can be synchronized to TX or RX clock of the LL Ethernet 10G MAC IP core.

Before the speed change, make sure the MAC TX and RX datapaths are idle with no packet transmission.

After the line rate changes, trigger a reset on the TX and RX datapaths by asserting these active-low reset signals, tx_rst_n and rx_rst_n.

1G/2.5G, 10M/100M/1G/2.5G/5G/10G (USXGMII), 10M/100M/1G/2.5G, 10M/100M/1G/2.5G/10G In 3