Hi, I’m having a similar issue to some that have been mentioned in other threads (e.g. Power Conditions) and it’s driving me mad trying to work out what’s wrong. So I wanted to check/clarify what the expected board behaviour “definitely should be” for the way the hardware is wired and try to figure out what’s happening in my case.
When battery power is connected is it expected that the board/nrf52 should start running without needing any button press? When I apply power the board does not execute code until the PWR button is pressed, at which point the BG96 starts flashing lights and then (after about 4 seconds) the NRF starts executing code. On applying power (and not pressing the button) there is no response on the JLink interface until the PWR button so I don’t think this is a case of the code being hung or crashed. (also if I reflash the original RAK firmware this behaviour remains the same)
I’m using a RAK5010, but with custom firmware (I can upload the source, it’s all to be open source but not quite ready, but I also see exactly the same issue if I upload a generic nordic example)
I’m using a board with a S340 softdevice but again I see this same behaviour if I reflash with no softdevice.
Finally… because I had wiped the flash to reset/program I found I needed to reprogram the UICR with the reset pin number to return that to function, is there any other UICR configuration I might be missing that might be causing this behaviour?
oh finally, finally, if I set a sense_input and use sd_power_system_off to enter system off, then the board does successfully restart on a GPIO signal.
any suggestions for what I would check, test or change?