Hi gang

Having a little Interrupt problems with the f877. 2 days and counting ):
I am using an ice2000 now to try and debug the problem with no joy.

Basically the GIE bit keeps turning itself off randomly and locking the
code. here is a simplified version of the code. Nops replace the main
program parts to simplify.
-------------------------------
interupt routine
        save context                    ;obvious
        btfsc   PIR1,TMR1IF             ;tmr1 int
        goto    timer1overflow

        other interupt stuff
        restore context
        retfie
timer1overflow
        bsf     overflowflag            ;set tmr1 interupt flag
        restore context
        retfie
-------------------------------
START
        set ports and normal stuff
        set up interupts
        BSF INTCON,GIE

MAIN    bcf     INTCON,GIE              ;turn ints off
        nop
        check for external signal w     ;part of my code
        nop
        bsf     INTCON,GIE              ;turn ints on
        nop
        call loop                       ;call sub
        goto    MAIN                    ;go again

loop    nop
        nop
        btfss   timer1overflowflag      ;has tmr1 int
        goto    loop                    ;repeat loop
        bcf     timer1overflowflag      ;clr flag
        return                          ;end sub
-----------------------------------
The program gets stuck in the loop when the GIE bit seems to randomly
clear itself??????? Any ideas

Scott

ccessories )
website:            www.broadcastwarehouse.com
email:              info@broadcastwarehouse.com

phone:
   sales:
        inland (uk) 0208 5409992
        international +44 208 5409992
   tech support:
        inland (uk) 0208 5409993
        international +44 208 5409993
fax     inland (uk) 0208 5409994
        international +44 208 5409994
*******************************************************

--
http://www.piclist.com hint: The list server can filter out subtopics
(like ads or off topics) for you. See http://www.piclist.com/#topics