> > Does
> >
> > BCF INTCON,GIE
> > BCF INTCON<GIE
> >
> > Have the same effect as:
> >
> > BCF     INTCON,GIE
> > BTFSC   INTCON,GIE
> > GOTO    $-2
>
>No.  Does
>
>     Flip a coin once
>     Flip a coin again
>
>have the same effect as
>
>     Flip a coin until it comes up "Heads"?

Interesting analogy, Andy, but I don't think it'll explain the problem to
him :)

The reason it doesn't work is that the initial problem you're trying to
avoid is in the clearing of the flag itself.  Whether you do it once, twice,
or 300,000 times in a row, it has the same problem: the flag bit can be set
by an interrupt after the BCF instruction is fetched, but before the INTCON
register is actually updated, thus overriding the BCF instruction.

You must use a loop to ensure that the flag bit was actually set.  I don't
know of another way around this.

--Andrew

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