> PICers - I have this code for a 16F84 that _should_ be pretty
straightforward. It loops around, looks for a bandit on RA4 (connected to IR
detector) fires camera if bandit is found. Trouble is the program freezes
when it it bcf/bsf's PORTB.
> Does it in ANIMATE on MPLAB (5.40) and also locks up when transferred to
an actual PIC on breadboad  :(

These symptoms don't make sense.  PICs don't just "freeze up" unless the
clock is stopped.  You can see the symptom in the simulator, so it should be
easy to chase down from there.  What happens when you single step over the
offending lines?  MPLAB will only show you source code lines that contain
pure instruction as apposed to macros.  Single step or animate (I'm not
familiar with animate, never used it) with the focus on the program memory
window, not the source windows.

>          bsf    POWER         ;Camera power is OFF. Active LOW
>          bcf    flags,CAM     ;Flag that power is OFF
> check    btfss  flags,HUNT    ;Still in hunt mode?
>           goto  shutdown          ;No  - then quit
>          call   watch                 ;Yes - look for a bandit
>          btfss  flags,BANDIT    ;Is a bandit present?
>           goto  check               ;No  - keep checkin'
> loop01   bcf    POWER        ;Yes - power up the camera. Active LOW
>          bsf    flags,CAM       ;Flag that power is ON
>          CAMWAIT               ;MACRO - Let the camera stabilise ~5 secs
>          call   watch              ;Look for bandit again
>          btfss  flags,BANDIT  ;Still there?
>           goto  check-2         ;No  - go back to to checkin'

Don't do this!  This is a bug waiting to happen because sooner or later you
will change something around CHECK, and this goto will break.  There is
absolutely no evidence by CHECK that other code assumes it can jump to
CHECK-2 for a known action.


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