Hardware Watchdog - RST vs EN

The forum has a lot on hardware watchdogs but they are mostly related to celluar and networked micros and not Xenons.

What is the difference between setting the RST pin low vs setting EN to GND? The documentation says:

|EN |Device enable pin is internally pulled-up. To disable the device, connect this pin to GND.|
|RST |Active-low system reset input. This pin is internally pulled-up.|

I would appreciate the community’s advice on:

  1. Does it matter which of these pins is connected to a hardware watchdog?

  2. For a Xenon, is it easier to use a “feather-based” external watchdog? Any ideas on a packaged solution. Would this also work:


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For my two cents worth, I found this guide on using the hardware watchdog built into the Nordic chip, which was straightforward to implement and appears to work well:

There is a link in the video description to the code base.

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Thank you @jmag

One main difference between EN and RST is that the RST pin only resets the main controller but not the NCP (ESP32 or ublox) while EN depowers both.

Thank you @Scruffr.