> Joe,
> 
> >    bsf                 INTCON,7  ;enable Global Interrupt
> 
> You should leave re-enabling of GIE to the retfie instruction, and
> clear INTF immediately before retfie, because any transitions whilst
> the ISR is being executed will cause INTF to be set again. This is
> less likely the faster the PIC is running but could happen as button
> noise is an unkown. The ISR will also be re-entered if any other
> enabled source causes an IRQ and GIE is on
> 

OK, I see that retfie resets the GIE. That would mean the initial 'bsf
INTCON,7' is not necessary?  Clearing INTF with retfie immediately following
will reenable the GIE to accept the next interrupt?

I really need to learn how to trigger an interrupt in MPLAB's debugger
utility.  Is simulating an external interrupt on RB0 even possible in debug?
The ability to use the watch is helpful, but I've not been able to see the
effects of an interrupt yet. 

> I would almost be tempted to have the debounce routine inside the
> ISR, however with GIE off that does prevent other sources triggering
> an interrupt. Although you could poll for them during the debounce
> 

We've learned how to do a switch debounce via subroutines so far.  I'm not
capable of thinking too far 'outside the box' yet.  :-)

Thanks for the help.  I have a few things to try now.

Joe


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