On Wed, 29 Oct 1997, Mike Keitz wrote:

> On Wed, 29 Oct 1997 00:50:32 -0500 Dave Celsnak <x93celsnak@WMICH.EDU>
> writes:
> >Just curious if any programmers can tell me if my ISR is LEGAL!
>
> Do you mean you'll get sued (and lose) for using it?  I doubt it, but I'm
> not a lawyer.
Just asking if it Legal, in the programming sense!
> It does appear that it will work. If you're trying to get
> exact timing, the clear of timer1 is a variable time after the interrupt.
>  This will cause inexact timing.

Where do you recommend to clear the timer1 variable?  Right after I check
for my compare interupt flag?
>
> If you go to a chip with more than 2K of program space, and use the extra
> space, you'll have to consider the possibility of interrupts occurring
> while bits 3,4, or 5 of PCLATH are set.  If that happens, the gotos in
> the ISR will go to the wrong page and the PIC will crash.
>
Just sticking with the 2K PIC 16c72 for now.

Do I have to save FSR, or any other registers???

Thanks, Dave