22.3.3.1 Normal Mode
In the Normal mode operation, a single time-out period is set for the WDT. If
the WDT is not reset from software using the WDR instruction during the
defined time-out period, the WDT will issue a system Reset.
Each time the WDT is reset by software using the WDR instruction, a new
WDT time-out period starts.
There are 11 possible WDT time-out periods (TOWDT), selectable from 8 ms to 8s by writing to the Period (PERIOD) bit field in the Control A (WDT.CTRLA) register.
The figure below shows a typical timing scheme for the WDT operating in Normal mode.
The Normal mode is enabled as long as the
Window (WINDOW) bit field in the WDT.CTRLA register is ‘0x0’.