unsigned short counter=0, counter2=0;

//Timer 0 initiallisations
void InitTimer0()
{
  //OPTION Register
  OPTION_REG.T0CS = 0; //Internal instruction cycle clock (CLKOUT)
  OPTION_REG.PSA = 0;  //Prescaler is assigned to the Timer0 module

  //PS2:PS0: Prescaler Rate Select bits, Prescaler 1:64
  OPTION_REG.PS2 = 1;
  OPTION_REG.PS1 = 0;
  OPTION_REG.PS0 = 1;


  TMR0 = 99; //Timer0 starts counting value

  //INTCON Register
  INTCON.TMR0IE = 1; //1 = Enables the TMR0 Interrupt
  INTCON.PEIE=1;  //Enables all unmasked peripheral interrupts
  INTCON.GIE = 1; //1 = Enables all interrupts

}


//isr
void Interrupt()
{
  if(INTCON.TMR0IF == 1)   //if timer0 interrupt occured
  {
     INTCON.TMR0IF = 0;  //reset timer0 interrupt flag
     TMR0 = 99; //Timer0 starts counting again

     counter++; //counts 1 second
     
     counter2++; //counts 2 seconds
     
     if(counter == 100)
     {
       counter=0;
       portb.b0 = ~portb.b0; //toggle led
     }
     
     if(counter2 == 200)
     {
       counter2=0;
       portb.b1 = ~portb.b1; //toggle led
     }


  }
}



void main() 
{
   InitTimer0(); //Timer 0 initiallisations
   
   //pin B0 as output
   trisb.b0 = 0;
   portb.b0 = 0;
   
   trisb.b1 = 0;
   portb.b1 = 0;

}