Low Latency 100G Ethernet Intel® FPGA IP Core User Guide: For Intel® Stratix® 10 Devices

ID 683100
Date 2/16/2022
Public
Document Table of Contents

7.8.2. AN/LT Sequencer Status

Provides the following status bits:
  • Link Ready
  • AN Timeout
  • LT Timeout
  • Sequencer mode for PCS reconfiguration

Offset: 0xB1

Access: RO

AN/LT Sequencer Status Fields

Bit Name Description Access Reset
13:8 seq_reconfig_mode Sequencer mode for PCS reconfiguration

6'b000001: AN mode

6'b000010: LT mode (Clause 93)

6'b100000: 100G data mode

All other settings are reserved

  • The sequencer modifies the datapath as required to move through the stages of AN/LT
  • This status register lets you know which step is in progress, and how the datapath is configured
RO 0x0
2 seq_lt_timeout Sequencer Link Training Timeout

1: Sequencer had LT Timeout

0: No timeout occurred

This status bit is sticky, and stays high until the next time LT restarts
RO 0x0
1 seq_an_timeout Sequencer Auto Negotiation Timeout

1: Sequencer had AN Timeout

0: No timeout occurred

This status bit is sticky, and stays high until the next time AN restarts
RO 0x0
0 seq_link_ready Sequencer Link Ready

1: The AN/LT Sequencer thinks the link is ready for data mode

0: Link not ready

  • This bit is determined by the RX PCS lane alignment status and hi_ber indication, depending on the setting of 0xB0[13] Link Fail if HiBER
  • If 0xB0[2] Disable Link Fail Timer is set, then the sequencer continues to indicate Link Ready and stay in data mode even if the link status goes down
RO 0x0