Transceiver Specific Checks - 2.6 English

1G/10G/25G Switching Ethernet Subsystem Product Guide (PG292)

Document ID
PG292
Release Date
2021-02-05
Version
2.6 English
  • Ensure that the polarities of the txn/txp and rxn/rxp lines are not reversed. If they are, these can be fixed by using the TXPOLARITY and RXPOLARITY ports of the transceiver.
  • Check that the transceiver is not being held in reset or still being initialized. The RESETDONE outputs from the transceiver indicate when the transceiver is ready.
  • Place the transceiver into parallel or serial near-end loopback.
  • If correct operation is seen in the transceiver serial loopback, but not when loopback is performed through an optical cable, it might indicate a faulty optical module.
  • If the core exhibits correct operation in the transceiver parallel loopback but not in serial loopback, this might indicate a transceiver issue.
  • A mild form of bit error rate might be solved by adjusting the transmitter Pre-Emphasis and Differential Swing Control attributes of the transceiver.