I think your issue is that the sleep time you specify is larger than a 32-bit value. This is not an issue for esp_sleep_enable_timer_wakeup as it takes a 64-bit value as an argument, but you're not calculating a 64-bit argument as uS_TO_S_FACTOR is specified as a long which is only 32-bit. My conver...

That's pretty much impossible to say from the coredump... can you show your code here?

Those lines normally get dropped in a sdkconfig.h that is generated after you configure the project for the first time. Simply build the project once and that file will exist and the issues should be solved.

Sounds like your modules/chips are wonky then. Sorry, without a scope this will get pretty hard to debug...

What exactly is 'after a while'? Is it reproducably the same time every time, or does it differ? I'm wondering if it could be a thermal issue... I also seem to remember that chips like the MAX7219 sometimes are faked, so where did you obtain them, from a reputable source like Digikey or from an Alie...

The IRAM_ATTR has very little to do with this. Your basic problem is that you cannot directly use an object method as a callback, as the information wrt *which* object the function is called on is lost. The solution for this would be to work around the issue by passing the object in the argument to ...

Can you show the code you're using?

It would help if you were to post the actual error...

Sorry, there is no such thing. If any, you can't shut down the idle tasks, so killing all tasks except the one running is no option. Killing the scheduler would stop you from doing anything that uses blocking functions, and your Error function seems to be full of them.

I don't think there is anything special you need to do wrt sockets in that example, as the UDP socket is bound to INADDR_ANY which means an incoming connection can come from any interface. Just bring both WiFi and Ethernet up (make sure they're not on the same network, though), and it should work.