>> What's odd is that the pin won't "come alive" again until the circuit
>> is powered down for a few seconds. A reset won't do it=20
>=20
> Interesting..

Not the word I've been using .......

> Have you tried swapping from GPIO5 to see whether the problem
> is unique to that pin?

The client has it at the moment trying a few physical arrangements of
the various parts of the product. He's not having much luck affecting
the reliability so I'm due to get it back soon. As it is such a frustrating
fault there's no love lost between me and the circuit so it'll be hacked
up for sure ;-)

I would like to know if the fault appears on any selected pin, but only
on the way to some sort of re-design, which will involve trying other
PICs to see if they are EMI 'harder' than the 12F675, if indeed that is
what turns out to be the problem

Had me up for two nights at the time with a scope and a selection of
filter components, to no avail. It was just as bad as when I started

As the intention is for a commercial venture, it does have to be sorted
out, so it's not just idle musings

Joe
--=20
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