#include <LiquidCrystal_I2C.h>
#include <Wire.h>

const int POT_PIN = A0; // Pin A0 for potentiometer
const float VOLTAGE_DIVIDER_RATIO = 0.5; // Resistance ratio for voltage divider circuit
const float REFERENCE_VOLTAGE = 5.0; // ADC reference voltage

// Initialize the I2C LCD interface (address 0x27, 16 columns, 2 rows)
LiquidCrystal_I2C lcd(0x27, 16, 2); 

void setup() {
  // Initialize serial communication at 9600 baud
  Serial.begin(9600);

  // Initialize the LCD display
  lcd.init();
  lcd.backlight();
}

void loop() {
  // Read the analog voltage from the potentiometer
  int analog_value = analogRead(POT_PIN);

  // Convert the analog value to a voltage in volts
  float voltage = analog_value * (REFERENCE_VOLTAGE / 1023.0) * VOLTAGE_DIVIDER_RATIO;

  // Convert the analog value to a string for printing to the LCD display
  char analog_string[7];
  dtostrf(voltage, 5, 2, analog_string);

  // Print the voltage in volts and the digital value in decimal format
  // to the LCD display and the serial monitor
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Voltage: ");
  lcd.print(analog_string);
  lcd.print(" V");
  lcd.setCursor(0, 1);
  lcd.print("Digital: ");
  lcd.print(analog_value);

  Serial.print("Voltage: ");
  Serial.print(analog_string);
  Serial.print(" V, Digital: ");
  Serial.println(analog_value);

  delay(100); // Delay for 100 ms before taking the next reading
}