I was beginning to wonder! :)  Usually, replies here are fast and furious.



>Assuming a Timer2 prescaler of 1:1, then the PWM frequency when PR2 = 255
>would be:
>((Fosc/4) / (PR2+1)) or
>  2,500,000 / 256 = 9,765.625 hz

Ok, that's what I was hoping. I didn't want to have to mess with both
registers to keep the freq the same.


>With an xtal frequency of 10Mhz, your choices of PWM frequencys that will
>still give you maximum 10-bit duty cycle resolution are:
>
>2,500,000 / 256 = 9,765.625 hz
>2,500,000 / (256 * 4) = 2,441.40625 hz
>2,500,000 / (256 * 16) = 610.3515625 hz

The chip giveth, and the chip taketh away..
I definitely need to switch better than 9.7k, looks like 7 or even 6 bits
is about the best I'll be seeing.

Ok, well at least I understand the machine now. Thanks :)
(Maybe the mfgrs should let us re-write their manuals for them!)


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