2.2.2 Resets from the Watchdog Timer (WDT)

One of the most common sources of reset is the Watchdog Timer (WDT). WDT is a special timer on the microcontroller designed to trigger a reset if the software fails to trigger a specific sequence(1) within a certain time interval. If the WDT is not needed(2) for the application, it can be disabled on the microcontroller using the configuration bits or fuses.

Note:
  1. The data sheet for the microcontroller will contain more information about the resetting sequence for the timer.
  2. Certain configuration modes of the WDT set it to operate only while running or when enabled in software. See the device data sheet for more information.