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Old 04-04-2014, 11:59 PM   #6399 (permalink)
MPaulHolmes
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Location: Maricopa, AZ (sort of. Actually outside of town)
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I'm getting close to being done with a complete rewrite of the code. I'm pretty sure there's a bug in the original software for the pwm filter. It tries to take sort of a running average for pwm, but look at this:

pwmAverage = (127*pwmAverage + 1*pwmNewValue)/128

Let's say, for instance, pwmAverage is 10, and pwmNewValue is 20. pwmAverage will never be able to creep toward 20. If the new value of pwm average is 10 < pwmAverage < 11, it will be truncated to 10, and won't ever get to 20.
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