morgan:
>Yes, but the same thing, from prescaler point of view, is already accomplished by the comf TMR0
instruction, >as you described, on the foregoing line?

exactly. 'clrf tmr0 / comf tmr0, F' does the same job as 'movlw 0xff / movwf tmr0' would do here (it
doesn't change W, but who cares?).
by making tmr0 0xff and clearing the prescaler, on the next clock you get tmr0=0x00 and prescaler =
0x01.
flip the PSA bit and the wdt should fire off straight away.

i'm not sure if you are asking me a question about my code or suggesting there's a problem with
it... could you clarify ?

Regards,
Simon

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