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I've got a custom ARM Linux 2.6.35-based platform I'm trying to get working. My problem is the Ethernet is not working consistently.

I've got a SMSC LAN8720AI PHY, with a i.MX283 uP/MAC @ 454MHz.

This should be using the FEC driver.

When it fails, LED1 blinks at about 11.68Hz. This is not in the datasheets of either the PHY or the uP/MAC... so I'm thinking it's a Linux driver thing. I haven't found it yet... does this ring a bell to anyone?

If I knew what the blinking meant, I might be able to isolate the problem. I've replaced chips, jacks, etc with little success.


I've finally found a single reference to an "about 10Hz" blinking experienced by someone on a PIC trying the exact same PHY. So, I'm going to assume it's an undocumented PHY error now (which the PHY vendor engineer I'm talking to doesn't know about). If anyone knows otherwise, please post.

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