AD Wandler in Atmega168

  // Enable ADC and set ADC- Prescaler

  ADCSRA |= ((1<<ADEN)|(1<<ADIF)|(1<<ADIE)|(1<<ADPS0)|(1<<ADPS1)|(1<<ADPS2));

  // Set voltage reference, result adjust and select input

  ADMUX |= ((1<<REFS0)|(1<<ADLAR)|(1<<MUX0)|(1<<MUX1));

  unsigned int count_1;

  unsigned int pwm_value;

  unsigned char direction;

  while(1)

  {

      if(ADMUX & ((1<<MUX0)|(1<<MUX1)))

      {

        ADCSRA = (1<<ADSC);

        pwm_value = ADCH;

      }      

    OCR0A = pwm_value;

  }