interrupt on pic16f689

void interrupt (void){
  unsigned char dummy; 
if ((INTCON.RABIF==1) && (PORTA.F0==1) && (INTCON.RABIE==1) )
{
     

         PORTC.F3 = 1;
           PORTC.F4 = 0;
         dummy = PORTA;     /// <- HERE!!!
         dummy = PORTB;     /// <- AND HERE!!!
         INTCON.RABIF =0 ;
         Delay_ms(500);
         PORTC.F3 = 0;
           PORTC.F4 = 0;
        


  }


                       }

void main() {

ANSEL = ANSELH = 0;                   //all pins I/o are cofigurred as digital
C1ON_bit = C2ON_bit = 0;              //Désactivation de deux comparateurs
INTCON.GIE =1 ;                         // Gener al interrupt enabled
INTCON.RABIE=1 ;
INTCON.RABIF=0 ;
IOCA = 1 ;                            //     PORTA cause an interrupt on lofic state change
IOCB = 1;

TRISA=1;                              // PortA  input
TRISB=0b00010000;                     //RB4 input , others output
TRISC=0b00000111 ;                     //portC RC0,RC1,RC2 input , others output
PORTC.F6=0;
PORTC.F7=0;
PORTC.F4=0;
PORTC.F3=0;                                                          



do {
if (PORTA.F0==1)  {
PORTC.F3=1;
PORTC.F4=0 ;
    }
    else if (PORTA.F1==1)  {
PORTC.F3=0;
PORTC.F4=1 ;
    }



}while (1);
}