Achronix Speedster22i Interlaken - Manual (Page 50)

Error Handling
The IIPC performs robust checking of all possible error conditions as described in the Interlaken
Protocol Definition including the following errors:
• a loss of lane alignment,
• a CRC24 error,
• a BurstShort violation,
• an illegal Control Word Type, or
• an illegal framing pattern is detected
If any of the above conditions are detected, the IIPC takes the following actions:
All open channels are marked as being in error and the packet in flight for these channels will
indicate the error condition by having rx_errout set to 1 when the corresponding rx_eopout is
asserted.
Additionally, in case of losing lane alignment, all data that is in the RX pipeline is lost.
It should be noted that, as per the Interlaken Protocol Definition, CRC32 errors do not affect open
channels or flow control. Additionally, bits in the stat_rx_mubits bus are unaffected by the errors
above and maintain their previous state.The error handling circuits in the RX path perform
EOP/SOP checks for Packet or Segment modes of operation. The signal listed below is used to
select what type of error checking is to be performed.
ctl_rx_packet_mode
The IIPC is designed to handle packets that arrive interleaved as segments. The IIPC ensures that
packets for each channel have appropriate SOP and EOP pairings. For applications that only send
complete packets, an SOP must be paired with the next EOP. To ensure this kind of checking,
Packet Mode, the ctl_rx_packet_mode should be assigned a value of 1. For Segment Mode,
ctl_rx_packet_mode should be assigned a value of 0.
Note: This input should be static and must only be changed during reset.
UG032, May 15, 2014 50