Bob Axtell wrote :

> 3. INT adds a lot of overhead. If all you need to do is set a 
> few flags in global registers, there is no need to save W,
> status, FSR, or PClath if all you need to do is set a few flags.

And, on the PIC18-line, that (saving of the "important" regs)
is done on the fly without any extra cycles. So *very* short
ISR's can be much faster on the 18's then on the 16's (if you
need the context saving).

And, yes, this doesn't work well (or at all) if you use both
interrupt priority levels, since there is only one set of
shadow context registers... Well, you can't get everything,
can you ? :-) :-)

Jan-Erik.



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