F767 EMAC Debugging Suggestions

kenny · ‎2016-10-29

Posted on October 30, 2016 at 02:22

Hi,

I'm attempting to bring up LWIP under FreeRTOS for an F767 on a Nucleo board. I'm using code generated by Cube. This is my third STM32 project and I'm very comfortable using an RTOS but I am just becoming acquainted with LWIP and the EMAC.

At the moment I'm simply trying to get DHCP to work. Basically I create a task, call MX_LWIP_Init(), and then loop/sleep(). With the device connected to a computer with a sniffer I am not seeing any activity.

I have probed the signals between the microcontroller and the PHY and believe that I have the GPIO configured properly.

The initialization code does not report any errors and I can see requests from the stack to call HAL_ETH_TransmitFrame().

LWIP debugging is enabled and it is telling me that it is trying to send DHCP discover UDP packets. Using a breakpoint I never see the ethernet IRQ called.

I'm curious if this solution is known to work on the F7. I suspect the EMAC IP is likely the same as an F4. Any ideas on what else to do for debugging?

Uwe Bonnes · ‎2016-10-31

Posted on October 31, 2016 at 18:03

Look at the most recent F76 errata sheet. RMII on F76 on;y work reliable on the most recent chip revision. I doubt that revision is out in the wild yet..

kenny · ‎2016-11-05

Posted on November 06, 2016 at 00:16

Thanks. I had the April 2016 errata. I'm not sure if this would make it unusable or if a CRC would fail and cause a resend when using TCP. From the MACs standpoint it seems that it would look like a corrupt packet?