> I am using a pot and the high resolution mode of an A/D on the 16f1828 .
> I am directly controlling a 10 bit PWM with the result of the 10 bit A/D
> input. I have a problem in that I want to avoid the noise of the A/D
> input from affecting my output. This happens if my pot is set just
> between two levels so the output fluctuates between two levels. Not very
> much only 1 or 2 levels out of the 1024 but this is significant in my
> application. I really only want the output to change if I physically
> move the pot. Currently I have fixed it by only outputting to the PWM on
> the output if the input changes by more than 2, assuming if it does I am
> moving the pot. This works in that my output is steady however it
> effectively lowers my resolution as well since the output now steps only
> when the pot moves more than 2 values. I was wondering if I should set
> up a timer interrupt for say 1 second and  if the output changes by more
> than 2  during that second assume the pot is being moved and allow level
> increments of 1. If it didn't move by more than 2 during that second
> assume the pot isn't being moved and lock the output. Am I on the right
> track here or can anyone recommend another technique .
> Jim

You could use an averaging technique to smooth out the transitions.
Something like this:

#define k=3D64;  // smoothing constant
static UINT16 SmoothValue=3D0;
SmoothValue=3D((SmothValue*k)+NewValue)/k;
return(SmoothValue);

Harold



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