use GPIOTE to reconfigure/simulate reset pin?

[fanoush]

Hello, I've read here https://devzone.nordicsemi.com/f/nordic-q-a/24490/nrf52-dk-changing-reset-pin-from-p0-21-to-somewhere-else that reset pin cannot be reconfigured to any pin except pin 21. Can I use GPIOTE with different pin somehow to cause SW reset without handling it with cpu? Like  pulling pin 21 down to cause reset when other pin is pulled down? Or possibly even with some delay like reset only if pin X is pulled low for e.g 1 second? It would be great if it worked even if cpu is halted, interrupts disabled etc. Thanks.

[Stian Røed Hafskjold]

You need to have an interrupt on the GPIOTE which handles the GPIO input. The CPU wakes up on the interrupt and calls the soft reset function. The CPU doesn't have to run all the time to catch the pin input.

[fanoush]

I guess  I could but I hoped I should not have to since the GPIOTE / PPI stuff is designed to do stuff automatically as configured without any interrupt and/or involving Cortex M CPU itself. Change on pin X would trigger change on pin 21. Question is whether this could be hooked into pin21 reset functionality somehow.

What you are describing is functionality of GPIO without the 'TE' part.

Also one point is to be as faithful as possible to real pin reset as described in this table so triggering soft reset from interrupt handler is not the same.

[Stian Røed Hafskjold]

The problem is that when p21 is configured as a reset pin you can not assign a GPIOTE task to it, so you can't trigger a pin reset without actually pulling p21 down unfortunately.