> The reason I said that TMR2 can make the calculations easier is
> that it has a period register, PR2

Yes, sorry, I overlooked that

As you say, a combination of the scalers and PR2 can be used to
get a timing period fairly simply from just about any crystal

The pricipal is true of other timers, except that a manual reload is
required and the timer counts up to an overflow IRQ rather than
being compared in the hardware, as is the case with TMR2/PR2

For example a 4MHz crystal, PR2 =3D 250, prescaler =3D 16, postscaler
=3D 10 would be 25 IRQs / sec

etc etc

The OP will have to decide based on his Fosc

Joe
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