Interrupt on timer

#include <p18f14k50.h>

//pragma codes
#pragma code high_vector=0x08
#pragma config FOSC = IRC //enable the internal oscillator




//function prototypes
void oscillator(void);
void timer(void);
void high_isr(void);

void interrupt_at_high_vector(void)
{
   _asm goto high_isr _endasm
}

/*******Oscillator function - This function will set the oscillator to 31 kHz***********/
void oscillator(void)
{
//Set oscillator to 31 kHz
OSCCONbits.IRCF2 = 0;
OSCCONbits.IRCF1 = 0;
OSCCONbits.IRCF0 = 0;

//Device clock derived directly from the LFINTOSC internal oscillator
OSCTUNEbits.INTSRC = 0;
}
/*******End Oscillator Function********************************************************/


/*******Timer function - Will start the timer and set pre-scalar to 1:128**********/
void timer(void) 
{
//Pre-scalar value of 1:128. This should give about 4 seconds for the timer0 interrupt flag to go high 
T0CONbits.T0PS2 = 1;
T0CONbits.T0PS1 = 1;
T0CONbits.T0PS0 = 0;

T0CONbits.TMR0ON = 1; //Enables Timer0
}
/*******End Timer Function********************************************************/

void main(void)
{
        INTCONbits.GIE = 1; //enable high priority global interrupts
        RCONbits.IPEN = 1; //enable priority levels on interrupts
        
        INTCONbits.TMR0IF = 0; //clears timer interrupt flag
        INTCONbits.TMR0IE = 1; //enable Timer0 interrupt bit
        T0CONbits.T08BIT = 1; //Set Timer0 as an 8-bit timer
        INTCON2bits.TMR0IP = 1; //Timer0 Interrupt bit set to high priority
        
        TRISC = 0x00; //set all PORTC bits as an output
        
        oscillator();
        timer();
}    

        
//High Interrupt Vector function
#pragma interrupt high_isr            // declare function as high priority isr
void high_isr(void)
{
    if(INTCONbits.TMR0IF = 1)
        {
            LATCbits.LATC0=1 //Turn on LED at RC0
        }
}

#include <p18f4620.h>

void interrupt_at_high_vector(void);
void high_isr(void);

#pragma config OSC = XT //Crystal oscillator
#pragma config WDT = OFF //Watchdog Timer off
#pragma config MCLRE = OFF //Master clear off
#pragma config LVP = OFF //LVP off
#pragma config XINST = OFF //XINST off

#pragma code high_vector=0x08
void interrupt_at_high_vector(void)
{
  _asm GOTO high_isr _endasm
}
#pragma code /* return to the default code section */
#pragma interrupt high_isr
void high_isr(void)
{
    LATC = 1; //RC0 HIGH
    INTCONbits.TMR0IF = 0; //CLEAR TMR0 INT FLAG
}

void main(void){
    TRISC = 0;
    LATC = 0;
    INTCON = 0xA0; //GIE AND TMR0IE
    T0CON = 0x85; //16-BIT, TMRON, PRESCALER 1:128
    while (1); //wait for interrupt
}

    LIST P=18F4620
    #INCLUDE <P18F4620.INC>
    __CONFIG _CONFIG1H, _OSC_XT_1H & _FCMEN_OFF_1H & _IESO_OFF_1H
    __CONFIG _CONFIG2L, _PWRT_OFF_2L & _BOREN_OFF_2L
    __CONFIG _CONFIG2H, _WDT_OFF_2H
    __CONFIG _CONFIG3H, _MCLRE_OFF_3H & _LPT1OSC_OFF_3H & _PBADEN_OFF_3H
    __CONFIG _CONFIG4L, _STVREN_OFF_4L & _LVP_OFF_4L & _XINST_OFF_4L & _DEBUG_OFF_4L
    __CONFIG _CONFIG5L, _CP0_OFF_5L & _CP1_OFF_5L & _CP2_OFF_5L & _CP3_OFF_5L
    __CONFIG _CONFIG5H, _CPB_OFF_5H & _CPD_OFF_5H
    __CONFIG _CONFIG6L, _WRT0_OFF_6L & _WRT1_OFF_6L & _WRT2_OFF_6L & _WRT3_OFF_6L
    __CONFIG _CONFIG6H, _WRTB_OFF_6H & _WRTC_OFF_6H & _WRTD_OFF_6H
    __CONFIG _CONFIG7L, _EBTR0_OFF_7L & _EBTR1_OFF_7L & _EBTR2_OFF_7L & _EBTR3_OFF_7L
    __CONFIG _CONFIG7H, _EBTRB_OFF_7H

    ORG 0x00
    GOTO MAIN

    ORG 0x08
    GOTO ISRH
;=================================================================================
ISRH
    BSF        LATC, 0 ;RC0 = 1
    BCF        INTCON, TMR0IF ;CLEAR FLAG
    RETFIE
;=================================================================================
MAIN
    CLRF    TRISC
    CLRF    LATC
    MOVLW    0xA0
    MOVWF    INTCON ;GIE AND TMR0IE
    MOVLW    0x85
    MOVWF    T0CON ;16-BIT, TMR0 ON, PRESCALER 1:128
WAIT
    GOTO    WAIT
;=================================================================================
    END
;=================================================================================