Window Mode

In Window mode operation, the WDT uses two different time-out periods; a closed Window Time-out period (TOWDTW) and the normal time-out period (TOWDT):

When enabling Window mode or when going out of Debug mode, the first closed period is activated after the first WDR instruction.

If a second WDR is issued while a previous WDR is being synchronized, the second one will be ignored.

Figure 1. Window Mode Operation

The Window mode is enabled by writing a non-zero value to the WINDOW bit field in the Control A register (WDT.CTRLA), and disabled by writing WINDOW=0x0.