> I am using a 32.768 watch crystal connected to Timer1. I'd
> like Timer1 to generate an interrupt exactly each 1.0000
> seconds. Should I load 16383 or 16384 to PR1? What it's
> not clear to me is if the value specified is ever reached in TMR1

Mario, you'd load -16384, ie 0xC000. 16384 is the number of
increments to get back to 0000. If you loaded -1, it would take
1 tick, -2 would take 2 ticks etc, all the way to -32768 (0x8000),
which is half the 2 seconds it takes for a free-running rollover

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