Setting GPIO before DeviceOS Update to disable a watchdog chip

Hi,
We have an external watchdog chip connected to the Argon. The enable for it is connected to a pin on the Argon but is also pulled up to enable it by default.
I have run into an issue where if a DeviceOS update is required that the watchdog is resetting the Argon during the update and breaking the update.

The documentation says that the application code will not get run if a DeviceOS is required so I cannot disable the watchdog here.

Is there anyway to set an IO pin to a state before the DeviceOS update starts?

Thanks,
Gary.

It’s not possible to set a pin before the update, because user firmware cannot run before the system dependencies are met.

There are three possible solutions:

  • Make your watchdog default to off
  • Make sure the time limit is long enough to complete an update. 7 minutes is usually enough, however there is a chance your watchdog will fire and interrupt the update once if you don’t have a way to reset the timer before reset
  • If you have a programmable watchdog, you can turn it off before the reset for a system update.

The last two techniques are shown in the watchdog application note.

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