We have a custom board running the SAM L21 (ATSAML21J18B-AUT) that we're trying to identify if it's a board issue or damage internal to the micro.
Essentially what happens is that an interrupt triggers a DMAC ADC capture. When the DMAC from ADC is complete an interrupt occurs and the data is processed. I have a pin toggle setup that shows the EIC portion is always working.
This system has been working for us for a while but now we're noticing that on some boards the DMAC interrupt never fires, however on other boards it works completely fine. This leads us to think that there is internal damage to the DMAC module OR the ADC module.
Is there anything we can do to narrow down what is happening to the Atmels? Is there a recommended procedure for populating the Atmels that if followed perfectly should help rule things out?
The fact that it works perfectly on some boards, but the DMAC never fires on others is leading us to think it's damage to the Atmels but if it is firmware related, is there anyway to be sure?