Ok, I've been doing some math, and I'd love a double check of my thinking.

I'm working on an 18F1320, and I'm looking to use TMR2 and TMR3 for
servo stuff. The chip is running off the 8MHz internal oscillator.

To generate the 20mS trigger, I'm looking at TMR2. If I setup the
prescale at 1:16 and the postscale at 1:10, then I think I should be
able to load the period register (PR2) with d'250' and get a 50Hz
interrupt.

Once I've got that going (I won't be able to try it until tomorrow)
I'll be looking at TMR3 to generate the 1mS to 2mS variable pulse. If
I setup TMR3 in 16 bit mode, with a prescale of 1:8, I think I can get
an interrupt at 1mS if I preload the timer register with 65286, and an
interrupt at 2mS if I load with 65031. So I should be able to take my
control value (from whatever, analog pot, data in, etc), subtract it
from 65286, and away I go.

Does that sound plausible?

Thanks!

Josh
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