nRF52 does not start without debugger

[ChrisG]

Hello,

I am experiencing an issue whereby the nRF52 is not starting up when not started through the debugger. I am using an identical setup as another project with regards to linker scripts and gcc_startup files and the issue is not present there.

Everything goes well when the debugger is attached and I start by debugging. Without debugging however, it does not reach main().

I have tried several approaches to correct this, running both with and without the softdevice. What I have seen is that I get atleast past SystemInit() (System_nrf52.c) where I set a gpio pin high that lit an LED as the very last call in the function so I could see I exited the function. Beyond this im not sure what is happening as it is not reaching main.

I have checked that the reset pin is high and CONFIG_GPIO_AS_PINRESET is set as per the other functioning project.

I am using Eclipse Mars2, gcc toolchain and the 132 Softdevice.

I should also note that I have tried various commands through nrfjprog and it still doesnt start up.

Do you have any suggestions as to what could be causing this behaviour?

Thanks, Chris

[RK]

can you start it without the debugger and then attach the debugger to it and find out where it is? I don't know how to do that with Eclipse etc, although it should be possible. You can certainly do it using jlink from the command line, quite hard work, but you should at least be able to find out where it's stopped, whether it's faulted or not and how it got there.

[Vidar Berg]

It sounds like semihosting might be enabled. Please try to remove --specs=rdimon.specs from your linker flags ( if you have it?) rebuild and see if you get the same result.

[ChrisG]

You got it in one. Thank you for your very speedy answer!

[knowic]

Hello,  sir, 

We have meet with similar issue, with 3~5% of all production PCB boards, but we didn't enable "--specs=rdimon.specs" option with the linker, Is there any other reasons you know can get into the same situation?

Thanks so much!

Jason Hu