There may be scenarios where the code, communications or attached peripherals causes a microcontroller to enter an undefined state and require external intervention to recover. Watchdog 1 eliminates the need of human intervention.

For use where unattended system reliability is required.

The Watchdog 1 module is independent of the microcontroller and triggers the reset pin if it detects abnormal operation (hard reset).

Features microcontroller voltage supervision - if the voltage is insufficient it will disable & hard reset the microcontroller via its' enable input pin. Additionally, it has the option to require 'patting' with a maximum interval of a 1.6 seconds. Where code in the micro controller is written to toggle an output pin in the main execution loop. If the loop fails to execute (e.g. hangs), the watchdog will hard reset the microcontroller.

Applications are where reliability, unsupervised / unattended operation and self-recovery is required.

The pinout of the Watchdog 1 module aligns with that of the ESP32 modules. It features a reset push button (MR - Master Reset) and a solder pad to enable the supervision of code execution by requiring a pat every 1.6 seconds.

Testing: works as expected with both main code faults and low voltage / unstable voltage recover.

Other findings: Exceptionally useful for low powered solar applications where a drained battery and low light can cause a microcontroller to start to boot but fails due to a sudden voltage drop as a low battery cannot support the current requirements. Watchdog 1 has been found to avoid a failed microcontroller boot due to such circumstances.