ofb_lane: Verification Report

1. Test results

Run on 2026-10-06 with GHDL 6.0.0 (mcode), VUnit 5.0.0.dev7, UVVM 2026.03.20: python run.py "*ofb_lane*" "*8b10b*".

Testbench	Tests	Passed
ofb_lane_tb (layer)	14	14
ofb_lane_init_tb (LN-1)	14	14
ofb_lane_rx_tb (LN-3)	8	8
ofb_lane_tx_tb (LN-2)	4	4
ofb_tb_8b10b_tb (verification component)	4	4

2. Summary

All 44 test cases pass; every requirement of the specification is covered (see the verification plan). VSG reports no errors and no warnings.

Defects found and fixed during verification:

Finding	Fix
Stat_FarCapability was not driven by ofb_lane	Connected to the capability register of LN-1
The consecutive LOST_SIGNAL / STANDBY counters kept their value through ClearLine, so a lane restarted into ClearLine at once when Started was reached (endless restart after a far-end LOST_SIGNAL)	Counters cleared on entry to ClearLine
After a sync reset the receiver could still use the last word received before	Sync reset discards the stored input word

Code coverage (QuestaSim, docs/coverage.md): the first measurement showed exit conditions of the initialisation states before Connected that no test exercised (LaneReset in Wait, Started and Connecting, NoSignal and timeout in Connecting, timeout in InvertRxPolarity, three STANDBY or LOST_SIGNAL words in Started, InvertRxPolarity and Connecting, iINIT2) and a realignment in CheckSync. TC-LN-33 and the extension of TC-LN-41 cover them and passed without a design change; every statement, branch and state machine transition of the layer is covered.

Observations:

• The 1023-word rule counts all words since the last RXERR; an INIT1 or INIT2 after more than 1022 error-free words moves to Connecting at once. This follows the wording of ECSS 5.5.2.7f.3.
• Behaviour on the line (8B/10B, SerDes) is covered by the behavioural model; the GTY wrapper test checks the real transceiver.