>I think Wouter meant why not use WDT ?  Interested in the reason myself.

That is what I understood as well, although more specifically why not use it
at high temperatures?

I suspect that is related to the temperature dependency of the WDT, as
others have noted (specifically Jinx, who has done a base calibration of a
16F84 against temperature IIRC). Hence I would suspect that at elevated
temperatures the WDT time may get very short, so one would need to clear it
more often. Could be a "gotcha when doing ambient bench development without
checking at temperature extremes.

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