what causes a AIRCR.SYSRESETREQ reset

[Timothy]

We have a working production system that is based on asset_trackerV2. It is working perfectly but there is a random event happening that I can not explain. On every reset I print out the cause of the reset based on the information in the nRF9160 data sheet for resetcause register. We have hundreds of boards out in the field and it seems that occasionally (one or twice a 24 hour period) I get a reset with a cause AIRCR.SYSRESETREQ. There is no commands or activity that should have caused this reset. It is a matter of concern to customers because we do not understand why the board is randomly getting reset. How do I determine what caused this reset. I see AIRCR.SYSRESETREQ if I flash the board from Visual Studio or I  issue a software reset but no one is doing either of these in the middle of the night. I would appreciate any guidance you can give on finding the cause of this reset.

[Charlie]

Hi,

It is weired. Can you open the link?  RE: 9160 Resetting and see the following reply from another developer in the thread:

It appears that a 3rd party library we are using is causing the reset. They are investigating this now.

I have tried setting CONFIG_REBOOT=n and it still resets and doesn't go through the fatal error handler. I'm wondering if it ends up being a NULL pointer exception because we are running non-secure and I read that non-secure doesn't properly catch NULL pointer exceptions.

I am unsure which third-party library he is using that could be causing this issue. For your reference, you might want to check the third-party libraries included in your setup.

This means that there could be different high-level reasons causing the reset. You will need to identify how to consistently reproduce this issue with your product. Please share more evidence and details if you’d like us to assist in analyzing the root cause.

Best regards,

Charlie