Is it possible to set any value to the Watchdog Timer? How can I change the underflow time of the Watchdog Timer?
No, it is impossible to set any value to the Watchdog Timer. When any value is set to the WDTS Register or WDTR Register, the value of the Watchdog Timer returns to "7FFFh", regardless of the set value. However, if the count source protection mode select bit (CSPR0) is "1", it returns to "0FFFh".
There are two ways to change the underflow time of the Watchdog Timer.
- Change the count source of the Watchdog Timer by the count source protection mode select bit (CSPR0)
- Change the division ratio of the prescaler of the Watchdog Timer by the prescaler select bit (WDC7 bit of the WDC Register)
Refer to the hardware manual for detail.