main{
  DDRB |= (1 << PB1) | (1 << PB2);

  DDRD |= (1 << PD2) | (1 << PD3) | (1 << PD4);
  sei();
  TCCR0 = 0x01;
  TCNT0 = 0;
  while (1)
  {
     //counter++;
       counter =  TCNT0;
      if (counter > 100)
        {
        //counter = 0;
          TCNT0 = 0;
          PORTB &= 0xF0;
        }

      if (counter >= PWM1)
        {
          PORTB |= (1 << PB1);
        }

      if (counter >= PWM2)
        {
          PORTB |= (1 << PB2);
        }
      if (counter >= PWM3)
        {
          PORTB |= (1 << PB3);
        }
  }
}