#include <LiquidCrystal.h> // Include LCD library

// Initialize the LCD (RS, EN, D4, D5, D6, D7)
LiquidCrystal lcd(12, 11, 5, 4, 3, 2);

// Define pin connections
const int gasSensorPin = A0; // Analog input pin for gas sensor
const int ledPin = 8;        // LED connected to digital pin 8
const int buzzerPin = 9;     // Buzzer connected to digital pin 9

// Threshold value (you can adjust this based on your sensor calibration)
const int gasThreshold = 300;

void setup() {
  lcd.begin(16, 2);           // Initialize a 16x2 LCD
  pinMode(ledPin, OUTPUT);    // Set LED pin as output
  pinMode(buzzerPin, OUTPUT); // Set buzzer pin as output
  pinMode(gasSensorPin, INPUT); // Gas sensor input
  
  lcd.print("Gas Detector");
  delay(2000);
  lcd.clear();
}

void loop() {
  int gasLevel = analogRead(gasSensorPin); // Read sensor value
  
  lcd.setCursor(0, 0);
  lcd.print("Gas Level: ");
  lcd.print(gasLevel);

  if (gasLevel > gasThreshold) {
    digitalWrite(ledPin, HIGH);    // Turn on LED
    digitalWrite(buzzerPin, HIGH); // Turn on buzzer
    lcd.setCursor(0, 1);
    lcd.print("!! GAS ALERT !! ");
  } else {
    digitalWrite(ledPin, LOW);     // Turn off LED
    digitalWrite(buzzerPin, LOW);  // Turn off buzzer
    lcd.setCursor(0, 1);
    lcd.print("Normal          ");
  }

  delay(500); // Small delay
}