#include <avr/io.h>
#include <util/delay.h>

uint16_t adc_value;
uint8_t toggle;
uint8_t bit_value;

void setup() {
  // put your setup code here, to run once:
  pinMode(3, OUTPUT);   // Tx
  pinMode(5, OUTPUT);
  pinMode(4, INPUT);
  pinMode(0, OUTPUT);
  // ADC Left Shift Result
  ADMUX |= 1<<ADLAR;
  // ADC Voltage Referrence
  ADMUX |= 0<<REFS2|0<<REFS1|0<<REFS0;        // Vcc is used as Voltage Referrence
  // ADC Input Channel/s
  ADMUX |= 0<<MUX3|0<<MUX2|1<<MUX1|0<<MUX0;   // Use ADC1 on pin PB4 as ADC input
  // ADC clock prescaler
  ADCSRA |= 1<<ADPS2|1<<ADPS1|1<<ADPS0;       // Use a divide by 128 Prescaler.
                                              // Sysclock = 8MHz, ADCclk = 62.5 kHz (max)
  ADCSRA |= 1<<ADEN;                          // Enable the ADC
  sei();
}

void loop() {
  ADCSRA |= 1<<ADSC;                          // Start the ADC conversion wait until conversion is finished.
  _delay_ms(100);
  adc_value = ADCL|(ADCH << 8);
  bit_value= ADCH & 0x01; // Extract ADCH[0]
  PORTB = (PORTB & ~(1 << 0)) | (bit_value << 0);
  if(adc_value<30000){
    digitalWrite(3, HIGH);
  } else{
    digitalWrite(3, LOW);
  }
  toggle ^= 1;
  digitalWrite(5, toggle);
  delay(1000);
}