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

LiquidCrystal_I2C lcd(0x27, 16, 2);

const int buttonPins[4] = {2, 3, 4, 5};
const int potPins[4] = {A0, A1, A2, A3};

void setup() {
    Wire.begin();
    lcd.begin(16, 2);
    lcd.backlight();

    for (int i = 0; i < 4; i++) {
        pinMode(buttonPins[i], INPUT_PULLUP);
    }

    lcd.setCursor(0, 0);
    lcd.print("HMI Ready");
    delay(2000);
    lcd.clear();
}

void loop() {
    for (int i = 0; i < 4; i++) {
        if (digitalRead(buttonPins[i]) == LOW) {
            lcd.clear();
            lcd.setCursor(0, 0);
            lcd.print("Pot ");
            lcd.print(i + 1);
            lcd.print(" Value:");

            int potValue = analogRead(potPins[i]);
            float voltage = (potValue / 1023.0) * 5;

            lcd.setCursor(0, 1);
            lcd.print(voltage, 2);  
            lcd.print(" V");

            delay(500);
        }
    }
}