>Wouldn't you lose less bits if you used a sawtooth instead of a square
wave or
>in fact any waveform that is repetitive without a step change or wild
>discontinuity in it ?

Maybe.

You actually end up with a kinda sawtooth going into the ADC.  The resistor
and cap work that part of it.  The PIC applies a square wave which is
filtered into a sawtooth by charging the cap through the resistor.

FWIW, I have 5K pots that I'm reading with 1M R1 and .47 C1.

Andy

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Andy Kunz - Montana Design - 409 S 6th St - Phillipsburg, NJ 08865
          Hardware & Software for Industry & R/C Hobbies
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