HPWM command and oscillator frequency

[mat janssen]

Because HPWM is taken from the internal timers and the internal timers are clocked from the xtal oscillator. The min. and max freq is depended of that.
If you take a very low xtal, you min. freq is than very low and you max. freq. is than also not so high.
Make a test and measure it thaan with an oscilloscope is alway good idea.

[RussMartin]

I put a scope on CLKOUT and looked at it and the PWM output pin.

Everything seems proportionate.

At the lowest oscillator setting (OSCON set for 125 kHz, so CLKOUT is 31.25 kHz),

HPWM 1,127,8000

gives a nice 250 Hz square wave.

Since the ratio of 4000/125 = 32, 8000/32 should (and does) equal 250.

I haven't determined maxima and minima yet, but I'll play with that next.