Taa for the replies to the MPLAB question. I also RTFM and found the way
to alter the INTCON bit to force the interrupt.

Next, Ohhh what a night:

Take this snipet-
        movf    rmax,w          ; load w with max time count
        xorwf   r1,f
        btfsc   _z              ; has the max time been reached

What I want to do is compare the value in rmax (value increasing each
interrupt) with a fixed value in r1, read in at the beginning of the
program from some BCD switches.

What I've realised is that the result of the XOR is then placed in r1,
overwriting the original data. My thinking now is to first transfer the
data from r1 to w and on to a temporary register and then test the
match. This would however mean doing this every pass (and in quite a few
locations).

Is this the best way of preserving the data in r1, or is there a better
way?

TIA,

--
Philip Martin   ----------------------------------------------------------------
Royal Quays             If at first you don't succeed, try again. Then quit:
North Shields.          no use being a damn fool about it !
                                                        W.C. Fields
email philip@philmart.demon.co.uk