Do any of you gurus know what the range of acceptable frequencies are for the HPWM command?
Using a 628 I'd like to know if I can get the full 8bit precision range at 140kHz on a 4MHz crystal or if I have to move to a 20MHz crystal. The PBP documentation is a little fuzzy on the details...it lists two different minimum frequencies for the HPWM at 4MHz, and says nothing about the maximum. Reason says that as you bump up the frequency that you'll lose precision (e.g. an upper frequency of 400kHz could only be split 10 ways by a 4MHz crystal so you'd have only roughly 3 bits of precision)...is it that simple to figure out that at 140kHz I'd have only log2(4000/140) bits of precision on a 4MHz crystal?
Also, if I change the duty cycle, does it always force the timer to restart at 0, or can I smoothly sweep the duty cycle?
I'm sure one of you folks have hit this problem before! Thanks, - Jim
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