Steve Smith wrote:
>
> The pic and most other cmos have intrinsic diodes in them the pull up
> resistor gives forard bias to these and the chip works but some times in a
> very strange manner. I have fallen into this hole more than once just when
> you thaught it worked properly suddenly it didnt.
>
> The only pin that hasnt got the diode is RA4 on '84 or equivelent pin on
> other devices the one that doubles as Vpp
>
> Cheers Steve.....

You can actually power the PIC (not recommended though) through an IO
pin.

--
Friendly Regards

Tjaart van der Walt
mailto:tjaart@wasp.co.za
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