I have a XIAO nrf52840 board. It has a button which does two things: one click seems to reboot the nrf52840 and double click enters bootloader mode. I'd like to override the default behavior and use the button in my own application (I want the reset button to also clear BLE bonding data). Is that possible? I couldn't find anything about the button in the board files but I guess it has to be connected to the nrf52840 somehow. Any tips on how to achieve this?
Update:
After reading the schematics here, it looks like the reset button uses pin0.18. It seems that p0.18 is a special pin which is configured by default to reset the chip? If that thread is correct, it looks like I could override the default behavior by setting CONFIG_GPIO_AS_PINRESET=n in prj.conf file. Now if I do that, I wonder if the "double click reset button to enter bootloader mode" would still work though. I am using the bootloader to flash the board so it would suck if it suddenly stops working.
I wonder if what happens is that the bootloader actually just listens to a single click when the MCU boots up. If that's the case I could enter bootloading mode by 1) unplugging/plugging the USB cable while holding the button 2) have my reset button handler trigger a reboot.
Any tips appreciated.
Update 2: "unplugging/plugging the USB cable while holding the button" doesn't seem to work. I am now wondering how the bootloader detects the double click. I didn't try option 2 yet because I'm afraid I might not be able to enter bootloader mode again.
