Hi guys,

I'm working on a little project and have just one i/o pin left in the
pict.  Two things about it, first, is that I feel that really must find
something for that pin to do as not to go to waste =) and, second, I would
really like to include a keyboard/keypad in this project.  I once saw a
"16-button analog keypad" circuit which used 1 pic i/o pin configured as
analog input, (obviously) 16 momentary switches and some resistors.  The
theory behind it was that for each key pressed, a different voltage would
be present to the analog input and the pic could tell what key was from
that voltage.

The only problem is that I tried all sorts of google search phrases and
can't find anything other than the usual 16 button keypad interfaces and
PC/AT keyboard interfaces.

Anyone here has a link or details about how this is implemented?  I would
be specially helpfull if you had a diagram WITH the resitor values in it
=) but I can try to come up with those values on my own if you have a
schematic (or a good explanation of how everthing is connected).

Thanks in advance.


-Mario
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