I am migrating a project to Nano 33 IoT from Wifi 1010 MKR where I used an I/O pin to pull the Reset pin down when needed the board to pragmatically reset itself. To prevent unwanted resets I added the following at the top of the Setup loop:
pinMode(resetPin, OUTPUT); // declared earlier: const int resetPin = 20; digitalWrite(resetPin, HIGH);
With GPIO20 hardwired to RESET I can send digitalWrite(resetPin, LOW); whenever a reset is required, and it works well on the MKR.
However, the Nano refuses to start with the I/O pin (in this case const int resetPin = 4) is wired to RESET pin, I assume it provides constant LOW to the RESET pin. I tried adding an external 1K pullup resistor but it didn’t work.