Sean Breheny <PICLIST@MITVMA.MIT.EDU> wrote:

> >> I'm using a 16C74A with two analog inputs. ADCON1 is set 04h, so I
> >> actually have three analog inputs. Is it OK to use the extra analog
> >> pin as an output, as long as I set TRISA accordingly?
> >
> > Yes, it's ok... Just remember that the PORTx bit corresponding to
> > that pin will always read "0", so read-modify-write instructions to
> > that port (including "BSF" and "BCF" instructions) will make that
> > pin pull low.
>
> When you say "will make that pin pull low", you mean if and when it
> is set to a digital output, right?

    Right, Sean.

> In other words, that pin will not attempt to output a low when it
> is configured as an ADC input.

    Correct; if the pin's TRIS bit is set to "1" (input), it will not
    pull low (whether or not it's configured as an analog input via
    ADCON1).

    -Andy

=== Andrew Warren - fastfwd@ix.netcom.com
=== Fast Forward Engineering - Vista, California
=== http://www.geocities.com/SiliconValley/2499