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Won't the watchdog timer be interrupted between 00h and tFFh to WDTR?

Latest Updated:09/22/2010

Question:

The watchdog timer is initialized by writing 00h and then FFh to the WDTR register. Won't the watchdog timer be initialized if an interrupt is generated between these two instructions?

Answer:

The watchdog timer will be initialized even if an interrupt is generated between the writing of 00h and FFh.
However, please note that the watchdog timer continues counting until FFh is written. Consequently, if the interrupt handling time is long, there is a possibility that the watchdog timer may underflow.
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