#include <stdlib.h>
#include <string.h>
#include <util/delay.h>
#include <LiquidCrystal_I2C.h>

 
#ifndef _BV
#define _BV(bit)        (1<<(bit))
#endif
#ifndef sbi
#define sbi(reg,bit)    reg |= (_BV(bit))
#endif
 
#ifndef cbi
#define cbi(reg,bit)    reg &= ~(_BV(bit))
#endif
 
#ifndef tbi
#define tbi(reg,bit)    reg ^= (_BV(bit))
#endif
#define 	loop_until_bit_is_clear(sfr, bit)   do { } while (bit_is_set(sfr, bit))

#define I2C_ADDR    0x27
#define LCD_COLUMNS 16
#define LCD_LINES   2

LiquidCrystal_I2C lcd(I2C_ADDR, LCD_COLUMNS, LCD_LINES);
 
void ADC_init() {
  sbi(ADMUX,REFS0);
  cbi(ADMUX,REFS1);
  cbi(ADCSRA ,ADPS0);
  sbi(ADCSRA ,ADPS1);
  sbi(ADCSRA ,ADPS2);  //64
  sbi(ADCSRA ,ADEN );
  //cbi(ADMUX,MUX0);
  cbi(ADMUX,MUX1);
  cbi(ADMUX,MUX2);
  cbi(ADMUX,MUX3);
  //sbi(ADMUX,MUX4);
  
}

uint16_t ADC_10bit() {
  sbi(ADCSRA ,ADSC  );
  loop_until_bit_is_clear(ADCSRA ,ADSC);

  return ADC;


}
double adcChannel0(){
  cbi(ADMUX,MUX0);
  uint16_t result = ADC_10bit();
  double V_result =double(result)/1023*5;
  return V_result;

} 
double adcChannel1(){
  sbi(ADMUX,MUX0);
  uint16_t result = ADC_10bit();
  double V_result =double(result)/1023*5;
  return V_result;
}
 
 

 double histereza = 0.5;
 
void setup() {

 ADC_init();
 lcd.init();
  lcd.backlight();
while (1) {
    double potencjometr = adcChannel0();
    double fotorezystor = adcChannel1();

  if (fotorezystor > potencjometr + histereza) {
    sbi(PORTB, 0);
    lcd.setCursor(0, 1);
    lcd.print("NOC  ");
} else if (fotorezystor < potencjometr - histereza) {
    cbi(PORTB, 0);
    lcd.setCursor(0, 1);
    lcd.print("DZIEN");
}


  lcd.setCursor(0, 0);
  lcd.print(potencjometr);
  lcd.setCursor(6, 0);
  lcd.print(fotorezystor);
  
  }
}