/*
 * Hello friends welcome back to "Techno-E-Solution"
 * Here is the complete Arduino Code Just Upload to the Arduino
 * Complete video tutorial:- https://youtu.be/Hfz3OumtENU
 */

#include<LiquidCrystal.h>
LiquidCrystal lcd(12,11,10,9,8,7);
int GasLED = A1;  // Gas LED
int Relay1 = 6;   // Exhaust Fan
int Relay2 = 5;   // Extinguisher System
int Buzzer = 4;
int MQ2Sensor = A0;  // MQ2 Sensor
int sensorValue = 0;
int FlameLED = A2;         // Flame LED
int FlameSensor = 2;     // Flame Sensor
int Flame = HIGH;        // Flame
//int REL = 11;
void setup() {
  pinMode(GasLED, OUTPUT);
  pinMode(Relay1, OUTPUT);
  pinMode(Relay2, OUTPUT );
  pinMode(Buzzer, OUTPUT );
  pinMode(MQ2Sensor, INPUT);
  pinMode(FlameLED, OUTPUT);
  pinMode(FlameSensor, INPUT);
  //pinMode(REL, OUTPUT);
  
  Serial.begin(9600);
  lcd.begin(16,2);
  delay (500);
    lcd.print("** SUBSTATION **");
    lcd.setCursor(0,1);
    lcd.print("...FIRE & GAS...");
  delay(2000);
    lcd.clear();
    lcd.print("DETECTOR SYSTEM");
    lcd.setCursor(0,1);
    lcd.print(" WITH PROTECTION");
  delay(2000);
    lcd.clear ();
}
void loop() {
  sensorValue = analogRead(MQ2Sensor);
  Serial.println(sensorValue);
   if (sensorValue > 300) {
   
    digitalWrite(GasLED, HIGH);
    digitalWrite(Relay1, HIGH);
    digitalWrite(Buzzer, HIGH);
    lcd.clear ();
    lcd.setCursor (0,0);
    lcd.print("GAS DETECTED");
    lcd.setCursor (0,1);
    lcd.print("EXHAUST FAN ON");
    delay (2000);
    
  }
  else 
  {
    
    digitalWrite(GasLED, LOW);
    digitalWrite(Relay1, LOW);
    digitalWrite(Buzzer, LOW);
    lcd.clear ();
    lcd.setCursor (0,0);
    lcd.print ("SYSTEM IS STABLE");
  }
  delay (500);
  Flame = digitalRead(FlameSensor);
  if (Flame == LOW)
  {
    digitalWrite(FlameLED, HIGH);
    digitalWrite(Relay2, HIGH);
    digitalWrite (Buzzer, HIGH);
    lcd.clear ();
    lcd.setCursor (0,0);
    lcd.print ("FIRE DETECTED");
    lcd.setCursor (0,1);
    lcd.print ("EXTINGUISHER ON"); 
    delay (2000);
    
  }
  else
  {
    digitalWrite(FlameLED, LOW);
    digitalWrite(Relay2, LOW);
    digitalWrite (Buzzer, LOW);
    lcd.clear ();
    lcd.setCursor (0,0);
    lcd.print ("SYSTEM IS STABLE");
  }
  delay (500);
}