We can measure RX signals from PHY but not TX signals coming from RT1176.

[mdribeiro]

Hello everyone,

We are developing a new ethernet application with NXP i.MX RT1176 and TI DP83826E, but we are facing a connection problem that we are unable to establish ethernet communication.

We are using DP83826 in basic mode and interfacing through RMII.

The link is stablished and we are able to see RX signals from PHY while we are pinging from a computer connected to the board. But we are unable to exchange messages between the board and the computer.

I would really appreciate it if you could help me with some suggestions.

[mdribeiro · Accepted solution]

Hello @Habib_MS, 

Thanks a lot for your message!

We found the problem thanks to your app note recommendation, it was a problem with "ref_clock" pin.

We changed "software input on" in MCUExpresso to "enabled" and ethernet worked well.

[Habib_MS]

Hello @mdribeiro,
In order to support you better, can you provide me the next information?

- Are you currently using an SDK example, if the answer is yes, can you share me the name and your SDK version?
- Which software stack was used for make ping in your board?
- " But we are unable to exchange messages between the board and the computer", can you provide me more context about this comment, for example the PHY does not emit a signal, or it is emitting a signal, but the computer cannot interpret the information, etc?
Also, I highly recommend see this app note in order to obtain more information about Ethernet Capabilities and PHY Connection of the RT1xxx series.

BR
Habib