#define ADC0 (0 << MUX3) | (0 << MUX2) | (0 << MUX1) | (0 << MUX0)
#define ADC1 (0 << MUX3) | (0 << MUX2) | (0 << MUX1) | (1 << MUX0)
#define ADC2 (0 << MUX3) | (0 << MUX2) | (1 << MUX1) | (0 << MUX0)
#define ADC3 (0 << MUX3) | (0 << MUX2) | (1 << MUX1) | (1 << MUX0)
#define ADC4 (0 << MUX3) | (1 << MUX2) | (0 << MUX1) | (0 << MUX0)
#define ADC5 (0 << MUX3) | (1 << MUX2) | (0 << MUX1) | (1 << MUX0)


int main(void){
  Serial.begin(9600);
  ADC_INIT();
  TIMER1_INIT();
  while(1){
    if(TCNT1 > 65000){
      TCNT1 = 0;
    }
  Serial.println(TCNT1);
  };
}


void ADC_INIT(){
  ADMUX = (0 << REFS1) | (1 << REFS0) | ADC0; //INTERNAL REF
  ADCSRA = (1 << ADEN) | (1 << ADSC) | (1 << ADATE) | (1 << ADIE)| (0 << ADLAR) | (0 << ADPS2) | (0 << ADPS1) | (0 << ADPS0);  // ADC ENABLE, START CONVERSION, ENABLE INTERRUPTS
  ADCSRB = (1 << ADTS2) | (1 << ADTS1)| (0 << ADTS0);             // TIMER1 COMPARE MATCH B
  DIDR0 = (1 << ADC0D);                                         // DISABLE DIGITAL INPUT BUFFER
  sei();
}

void TIMER0_INIT(void){
  TCCR0B = (0 << CS02) | (0 << CS01) | (1 << CS00);
}

void TIMER1_INIT(void){
  //TCCR1A = (1 << WGM11) | (1 << WGM10);
  TCCR1B = (1 << CS12) | (0 << CS11) | (1 << CS10);  
  //TCCR1C = ();
  TIMSK1 = (1 << OCIE1B) | (1 << TOIE1);
  //OCR1B = 20000;
}

ISR(ADC_vect){
  //Serial.println(ADC);
  //Serial.println(TCNT1);
  Serial.println(ADC);

  ADCSRA |= (1 << ADSC);
}