I put my code on a nucleo board, and the loopback test works, so I don't think it's my code. This problem occurs only on our setup. I have included a schematic of our setup so you can see it clearly. The loopback mode is enabled by setting the l...
We cleaned up the signal, and we got loopback to work on a 1.8V nucleo. The key issue was here: GPIO_InitStruct.Pin = ETH_TX_EN_Pin|ETH_TXD1_Pin|ETH_TXD0_Pin; GPIO_InitStruct.Mode = GPIO_MODE_AF_PP; GPIO_InitStruct.Pull = GPIO_NOPULL; GPIO...
This is a screen capture of a scope trace of TXD1. This signal looks strange. We disconnected TXD1 from the phy so we could see only what was coming out of the MCU. Any ideas why this is happening?
Yes, that seems like a good theory. I am curious why the nucleo succeeds at this while we fail on our board. I looked for differences in the code, but to no avail.
ETH_MACCR = 0x3830E003 so FES is set to 100Mbps per seconds, and DM is set to 1 which means full duplex. BSR = 0x782d which indicates that auto-negotiation is complete.