If you leave the capacitor out and read the value with an AD it is very=20
simple to construct & program.
That is the scheme used in the popular LCD Display + pushbutton switches=20
offered by many vendors.

On 7/18/2013 12:30 AM, YES NOPE9 wrote:
> There may be up to 10 pushbutton switches.  Only one may be pressed at a =
time.
> Each of the resistors [ R0 thru Rn ] is 10K.  C1 is 0.1 uf .  Rcal is 100=
K .
> At startup the PIC configures a pin as an output and pulls C1 to a*one*.

--=20
John Ferrell W8CCW
"The pessimist complains about the wind;
The optimist expects it to change;
The realist adjusts the sails."
      William A. Ward

--=20
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