#include <Wire.h>
#include <LiquidCrystal_I2C.h>
LiquidCrystal_I2C lcd(0x27, 20, 4);  // Adjust according to your LCD module
// Pin definitions
const int gasSensorPin = A1;   // Analog input pin for MQ-2 sensor
const int ledPin = 13;          // Digital output pin for LED
const int buzzerPin = 6;       // Digital output pin for buzzer
// Threshold value for gas detection
const int threshold = 500;     // Adjust this value based on your calibration
void setup() {
  Serial.begin(9600);          // Initialize serial communication
  pinMode(ledPin, OUTPUT);     // LED pin as output
  pinMode(buzzerPin, OUTPUT);  // Buzzer pin as output
  // Initialize LCD
  lcd.init();
  lcd.backlight();
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Gas Leakage");
}
void loop() {
  int sensorValue = analogRead(gasSensorPin);  // Read analog value from sensor
  Serial.print("Gas Sensor Value: ");
  Serial.println(sensorValue);
  // Update LCD with sensor value
  lcd.setCursor(0, 1);
  lcd.print("Sensor: ");
  lcd.print(sensorValue);
  // Check if gas concentration exceeds threshold
  if (sensorValue > threshold) {
    // Gas detected, activate LED and buzzer
    digitalWrite(ledPin, HIGH);
    digitalWrite(buzzerPin, HIGH);
    lcd.setCursor(0, 1);
    lcd.print("Gas Detected    ");  // Update LCD with alert message
    delay(1000);  // Delay for 1 second
  } else {
    // No gas detected, turn off LED and buzzer
    digitalWrite(ledPin, LOW);
    digitalWrite(buzzerPin, LOW);
    lcd.setCursor(0, 1);
    lcd.print("                ");  
  }
  delay(1000);  
}