>  Reverse-inserted batteries promptly go flat.  "Darn batteries!"
>Properly inserted ones last for "ages".  Appliance always works if
>good batteries inserted correctly.  This is the "teaching" approach.

Why not just power the PIC through it's I/O pins.  If you are dealing with
low current, this works great.

For instance, if RB.0 and RB.1 are your "power" pins (tie MCLR to regular
VCC pin!)

        movf    RB,0
        movwf   RB
        bsf     RP0
        movlw   xxxxxx00
        movwf   RB
        bcf     RP0

This will cause your power rails to be connected about as directly as
possible, and still not have to worry about battery polarity.  If you're
smart about it, you can power your entire circuit _through_ the PIC if you
keep the currents low.

Andy
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