I have a chance to work with the 25G Ethernet IP in one of the Stratix 10 SI Kit with an external loopback cable today. Below is my finding:
1. Transceiver Toolkit is NOT stuck with the following conditions:
- Open Toolkit with no connection, and then connect it with an external loopback cable
- Disconnect the loopback cable halfway the transceiver link test
2. We just need to connect an external loopback cable, and the link is UP consistently. This is without required to “press” start transceiver link. The link is “up” referring to the “RX CDR is locked to data”, it always shows “locked” in transceiver Toolkit. Therefore, this is suggested to check the requirement of the link pattern whether the PRBS checker is always on and that may cause the problem.
3. I’m not aware, and this is not clear about PRBS is inverted. More clarification is needed if further investigation is required.