WDT Times Out Prematurely ( nRF9160 )

[phipi]

We're experiencing occasional unexpected hardware watchdog resets. The watchdog is set to 10 minutes, and sometimes just 2 minutes after feeding the WDT we see a reset triggered with the watchdog being specified as the reset reason on boot. Are there any known issues with the WDT? Any thoughts on what might be causing this?

[MJD093]

Have you tried setting the WDT to a smaller value to observe how the WDT behaves?

I have WDT set to 5 seconds and observe no unexpected issues with the WDT.

[phipi]

Yes, we have but it's not always practical in our code. Also, the 10 minute timeout seems to work 95% of the time so I'm concerned with masking the issue by simple decreasing the period.

[MJD093]

When you say 95% of the time. Over how much time on average does the issue manifest? Immediately after boot, hours, days?

[phipi]

There's no real predicable pattern. We've seen it minutes after boot and days after boot

[MJD093]

What exactly is the device doing when it does trip if it is possible to know. Does it trip at the same point everytime or randomly?

[phipi]

It has definitely happened in different parts of the code but there's no way to know exactly when so there's a chance it was performing similar types of tasks when it happened.