Hi I posted a bug just now.
https://github.com/apache/incubator-nuttx/issues/136 I forgot to mention in the ticket I'm building from master at e59f242. I feel bad for throwing out a report without finding the cause but I'm pulled in many directions this month. The issue appears to be in code which has seen a lot of refactoring within the last few weeks so hopefully it will ring some bells. I'll try to contribute more productively next time! Does anyone have a feel for the last known stable tag wrt Ethernet networking on STM32F4? Cheers Rob