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TSchu3's avatar
TSchu3
Icon for Occasional Contributor rankOccasional Contributor
1 year ago

Arria 10 Gx board, SFP connection no link

Hello all, I am attempting to bring up a link on a new Arria 10 Gx board, using the SFP+ connector. I started by generating an example design for the Low Latency Mac, with the 1G/2.5G Ethernet Examp...
Fpga Devkit
ZiYing_Intel's avatar
ZiYing_Intel
Icon for Frequent Contributor rankFrequent Contributor
1 year ago

Hi,


Could you try to do internal loopback on the device to check whether the device can function normally?


Best regards,

Zi Ying



TSchu3's avatar
TSchu3
Icon for Occasional Contributor rankOccasional Contributor
1 year ago

Hello, I have had success in getting the LL10G_10G_USXGMII example project (posted earlier) to connect.
I had to turn off USXGMII Mode and revert to 10GBase-R mode. I am not sure why this affected the link but it allowed me to proceed.
I am now able to send and receive data at 1G speeds.

I have one remaining issue. The internal PHY port 'operating_speed' always shows as "000" which I believe corresponds to at 10G connection. This is true even when I am connected to 1G or 2.5 G only devices. So it is not updating to the correct current speed.

How can I get reliable information from the PHY internally about its current connection speed? I do not see a register that I can read which will tell me this information. How can I limit the allowed connection speeds? For example, If I cannot run at 10G speeds I do not want the PHY to be able to connect to 10G only devices.

Thanks