I have tried to replicate what little there are of simple examples for LwIP stack using F7xx Nucleos. The example i am testing is a trivial web server servicing simple http GET's. It kinda works but very sporadically and the question i have is if there are known issues with this combo.
- Ethernet and ADC defined in CubeMX, as well as FreeRTOS and LwIP,
- toolchain is SW4STM32 i.e. Eclipse, OpenOCD, St-Link,
- I have mangled the project into C++, not that it should have any effect on this particular issue but who knows.
The specific problem i have is that ARP works very sporadically. I run Wireshark in the debugging host so i can see the traffic on Ethernet wire and it is obvious that ARP fails almost consistently. The LwIP stack should issue a sporadic ARP broadcast upon start but this is almost never seen. Also ARP queries from the http client (same host that runs debugger) usually go unanswered.
Occasionally there is a response to an ARP query and then the http GET immediately succeeds so it is obvious the problem is in ARP not working properly.
I have traced the code and the call to issue a sporadic ARP bradcast is called consistently, but mostly does not result in an ARP packet showing on the wire. So what gives? Is the Nucleo Ethernet hardware flaky or is there some other (hopefully known) issue?
P.S. My code never worked at all on a Nucleo F767, but works significally better on a Nucleo F746. Not well, but sometimes at least.