Help with configuring

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:

Code:

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#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.

Anyone?????

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 ?

Here you are:

Code:

---

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

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

I missed that.

Code:

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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

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dt ints is easier

I know that. But latency causes problem.

Quote:

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Originally Posted by financecatalyst

I know that. But latency causes problem.

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

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