Hello,

I have been working on my first project using a PIC12F675.  This is a
low powered battery operated device that should stay in sleep mode until
woken up by a button press to do it's thing.

I am using INTF to wake up from sleep.  I have followed the manual and
ensured that the comparator is off and that  the ADC is switched off.
However the interrupt doesn't behave as I expect it should.  as soon as
GIE is set, execution branches to the ISR, even though there has been no
+ve going edge to trigger the interrupt.  GPIO2 is tied low until it is
pulled high by the press button.

The test code below shows how I have initially set up the GPIO pins in
the 'main' routine.  I would expect that GPIO0 would toggle until the
switch is pressed but instead GPIO1 will toggle.  It appears however
that the '
'bsf   GPIO, 0' statement after GIE is executed, as GPIO, 0 goes high
before the ISR is executed.

Perhaps I am missing something in my GPIO initialization??  Any help
would be greatly appreciated.

John

;==============================================================================
; intf_test.asm --
;  Bare bones quick test to see why INTF doesn't work properly in
vibeclock.asm
;
;==============================================================================
        list p=12f675
        include "p12f675.inc"
        __idlocs 0x6789
        __config   _MCLRE_OFF & _BODEN_OFF & _CP_OFF & _PWRTE_ON &
_WDT_OFF & _INTRC_OSC_NOCLKOUT


    messg "INTF Test"

    org    0x00
    goto    main

    org    0x04

    bsf    GPIO, 1
    nop
    bcf    GPIO, 1
    goto    $-3

main
;; Initialize I/O pins
    clrf    GPIO

    ;; Turn comparator OFF
    movlw     0x07
    movwf     CMCON

    ;; Switch to Bank 1 to initialize registers in that bank
    bsf    STATUS, RP0

    ;; Ensure ALL inputs are digital inputs initially
    clrf     ANSEL

    ;; Initialize TRISIO
    movlw    b'11111100'
    movwf    TRISIO

    ;; Initialize OPTION_REG
    movlw    b'11011111'
    movwf    OPTION_REG


    bcf    STATUS, RP0     ;Bank 0

    bsf    INTCON, INTE
    bsf    INTCON, GIE

    bsf    GPIO, 0
    nop
    bcf    GPIO, 0
    goto    $-3

        end

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