In a message dated 5/4/99 8:09:41 AM Pacific Daylight Time,
support@MONTANADESIGN.COM writes:

<< I remember VERY recently that there was an app note or tech brief on how to
 make pin GP3 on a PIC12C part to act as an output.

 Does anybody know where I saw that?  Pleeeease?

 The idea is basically to use turn the pull-up feature on and off, using
 that to switch a transistor on and off.

 Thanks!

 Andy
 ================================================================== >>
Hi Andy,
It was in the microchip App notes.  I have seen it too.  I think I could find
it again if you can't.  I think it was in the design contest section.
The problem I remember with this approach was the response time.  It would
work if your intent is turn on and off a LED, light or sprinkler valve, but
it is useless for doing PWM or somthing that requires timeing less than a
second.  It used an external transistor to detect the presents of the weak
pullup on that pin.  You can effect an output by turning on and off the
pullup for that pin.

Regards
Dave Duley