I need help for a very urgent case about M4 in Customer Product.
Customer found their product will totally stop working if put strong EMI source close to the M4 device for a while (around 1 hours), in this case, M4 all pin function stop working forever without any respond. (it means even watchdog donot work to reset)
Unless device external reset or power on again, it resume to work. (it means device is not damage and internal code is safety)
We double confirm the watchdog function by remove the “Clear Dog” code then run customer product in normal environment, M4 will be reset by watchdog. (it mean watchdog code should be not problem, however watchdog just do not work when device in stop working issue)
We want to know which possible reasons could cause M4 Totally Stop Working even watchdog is also not functions.
Wish get help some advice today, because We are required to do the test and confirm the root case by tomorrow.
Because TOP End-Market report such issue, it give very bad affection to customer and they pay much attention on this case.