ISR(TIMER1_COMPA_vect){
 OCR1A += 100000;
 PORTB=PORTB ^ 1 << 2 ;
}

ISR(TIMER1_COMPB_vect)
{
   OCR1B += 100000/2;
   PORTB=PORTB ^ 1 << 1 ;
}

ISR(TIMER1_OVF_vect) { 
  PORTB=PORTB ^ 1 << 0 ;
}

void setup() {
    DDRB = B11111111;
    TCCR1A = TCCR1B  = 0;
    OCR1A = 100000;
    OCR1B = OCR1A /2;
    TCCR1B |= B00000011;  
    TIMSK1 |= B00000111;     
}

void loop() {
}