Crash due to softdevice assert (id:0x1 pc:0x1089E info:0x0)

[Eddie]

Hi. We are using the nRF52 sdk v12.1 with S132 v3.0.0 on a nRF52832. Once in a while (could be after running a few hours, could be after running a week) the application ends up in the app_error_fault_handler, with id 0x01, pc 0x1089E and info 0x0. I believe this indicates an assert in the softdevice? What could cause this problem? Is there any way we can investigate this issue? Is there a way to recover from this?

I'm not even sure what information would helpful to find out where the problem is. We advertise at a fast pace all the time (20ms), and there are several timers running in the background. Application is communicating through the BLE NUS, but only sporadically. We also have a TWI running to communicate with an external device.

Anyone know an idea on how to handle this problem?

[Turbo J]

Check TWI IRQ priority.

[bds]

It's APP_IRQ_PRIORITY_LOW.

[Kenneth]

Hi, I suspect you are blocking interrupts (e.g. critical region enter) for a long period of time.

Best regards,
Kenneth

[Eddie]

We are using critical regions, but only copy some data in them at this point. We logged the time inside critical regions and never use more than 1ms. Some of the critical regions are nested though, could that cause a problem?

[bds]

The critical region enter macro only disables application interrupts, right?

How can it then cause a Softdevice assert?

What time is acceptable to spend in a critical region?