SerialLite II IP Core User Guide

ID 683179
Date 7/13/2021
Public
Document Table of Contents

2.8.15. Error Handling

The SerialLite II IP core does error checking and has an interface to view local errors. The errors are categorized, and the effect of an error depends on the type of error that occurs.
The SerialLite II IP core has three error types:
  • Data error
  • Link error
  • Catastrophic error
Table 15.  Error SummaryThis table summarizes the causes and results of the SerialLite II error types.
Error Type Cause Action
Data
  • Invalid 8B/10B codes groups
  • Running disparity errors
  • Unsupported valid code groups
  • Link protocol violation
  • LMP with BIP error
  • CRC error
  • Unexpected channel number
  • Out of order packet
  • Out of order acknowledgment (if Retry-on-error is enabled)
Two possibilities:
  • If Retry-on-error is enabled and the packet is a priority packet, request retransmission.
  • Otherwise, mark the packet as bad and forward it to the user link layer.
Link
  • Eight consecutive {|TS1|} sequences received in all lanes simultaneously
  • Loss of character alignment
  • Loss of lane alignment
  • Loss of characters from underflow/overflow
  • Data error threshold exceeded
  • Retry-on-error timer expired three times
Trigger link initialization
Catastrophic
  • LSM cannot reverse polarity
  • LSM cannot reorder lanes
SerialLite II enters nonrecoverable state
Packets Marked Bad {EBP} marked packet Received packet is marked as bad through the rxrdp_err or rxhpp_err signals, and forwarded to the user link layer.
Error signals, such as txrdp_err and txhpp_err, are asserted by user logic.
  • When txrdp_err is asserted with txrdp_eop, the packet is marked with the end of bad packet {EBP} marker.
  • The txrdp_err signal is ignored when it is not asserted with txrdp_eop.
  • When the txhpp_err is asserted and the Retry-on-error feature is turned off, the packet is marked with the {EBP} marker.
  • When the txhpp_err is asserted and the Retry-on-error feature is turned on, the packet is not transmitted and is silently dropped.