Help with configuring

[financecatalyst]

Hello there. I have written a simple code but it seems not to work properly. I am not sure what I am missing here and any help will be appreciated.

The code is as follows:

#CONFIG
    ifdef PM_USED
        device  pic16F688, intrc_osc_noclkout, wdt_on, mclr_on, protect_off
    else
        __config _INTRC_OSC_NOCLKOUT & _WDT_OFF & _PWRTE_ON & _MCLRE_OFF & _CP_ON & _CPD_ON & _BOD_ON & _IESO_ON & _FCMEN_ON
    endif
#ENDCONFIG
DEFINE OSC 8       ' OSCCON defaults to 8MHz on reset
DEFINE NO_CLRWDT 1
Include   "modedefs.bas"

' declare the interrupt handler
define INTHAND _ISR

goto main

ISR:
asm

; my asm code

endasm

main:
        PAUSE 50
	OSCCON = %01110001 ' Internal Oscillator 8MHz
        TRISA = %000100
        TRISC = %000010
        CMCON0 = 7
        ANSEL = 0               ' NO ANALOGS
        OPTION_REG = %10000011  ' RAPU = off, PS 1:16 to TMR0
        PORTA=0
        PORTC=0
        
        ' setup iZCD to interrupt on change
'        INTCON= %10110000
        '         |         Global interrupts enabled
        '           |       Timer0 interrupt enabled
        '            |      Zero Crossing interrupt enabled
        '             ----  Flags are cleared
 while 1
	toggle PortA.4
	pause 500
wend

When I comment the INTCON, my led blinks fine @ 500mS. When I uncomment it, the timings go out.
I want to run my PIC16F688 at internal 8MHz and not sure if I am missing any configuration register.

[financecatalyst]

Anyone?????

[richard]

if you enable interrupts and provide no code to service the interrupt and worse still provide no code to reset the interrupt flag what do you expect to happen ?

[financecatalyst]

Here you are:

ISR:
asm
        movwf   wsave           ; Save WREG
        swapf   STATUS, W
        clrf    STATUS          ; Point to bank 0
        movwf   ssave           ; Save STATUS
        movf    FSR,w
        movwf   fsave          ; save FSR
        movf    PCLATH, W       ; Save PCLATH
        movwf   psave


        ; get ready to jump within the ISR page
        movlw   ((INTHAND) >> 8) ; Set PCLATH for jump
        movwf   PCLATH
        btfsc   INTCON, INTF
        goto    ZeroCrossingInt

T0Overflow
        bcf     INTCON, T0IF    ; clear the timer overflow flag

        goto    EndInt

ZeroCrossingInt
        bcf     INTCON, INTF    ; clear the interrupt

EndInt  ; restore the machine state and return from interrupts
        movf    fsave,w
        movwf   FSR             ; restore FSR
        movf    psave,w
        movwf   PCLATH          ; restore PCH
        swapf   ssave,w
        movwf   STATUS          ; restore Status
        swapf   wsave,f
        swapf   wsave,w         ; restore WREG
        retfie
endasm

[richard]

I cant see that you have declared wsave ,ssave and psave vars ?

[financecatalyst]

I missed that.

wsave       var byte    $70     SYSTEM          ' safe for W in all banks
ssave       var byte    BANK0   SYSTEM          ' save STATUS
psave       var byte    BANK0   SYSTEM          ' save PCLATH
fsave       var byte    BANK0   SYSTEM          ' save FSR

[richard]

dt ints is easier

[financecatalyst]

I know that. But latency causes problem.

[mackrackit]

I know that. But latency causes problem.

What latency? I have never noticed any with DT's INTS.

[Dick Ivers]

Suggestion: Simplify your job by switching to a 16F1823. Same pinout as your present PIC but with automatic context saving.