#include <LiquidCrystal_I2C.h>

/* Display */
LiquidCrystal_I2C lcd(0x27, 16, 2);

const int buttonPin = 2;
const int potPin = A0;
int gasValue = 0;
int buttonState = 0;
int lastButtonState = 0;


void setup() {
  lcd.begin(16, 2);
  pinMode(buttonPin, INPUT);
  lcd.setCursor(5, 0);
  lcd.print("SENSOR");
  lcd.setCursor(1, 1);
  lcd.print("PENDETEKSI GAS");
  delay(1000);
}

void loop() {
  buttonState = digitalRead(buttonPin);
  if(buttonState == HIGH && lastButtonState == LOW){
    int potValue = map(potValue, 0, 1023, 0, 100);
    lcd.clear();
    lcd.setCursor(0, 0);
    lcd.print("BESAR GAS : ");
    lcd.print(gasValue);
    delay(500);
  }
  lastButtonState = buttonState;
}