Virtual IoT Lab DEI

Interfacing of Arduino with MQ135 :

Use the slider to move smoke towards or away from MQ135 sensor.

ARDUINO CODE

#include "Wire.h"
#include "Adafruit_LiquidCrystal.h"
Adafruit_LiquidCrystal lcd(0);

#define BUZZER 6
#define RED 4
#define BLUE 3
#define GREEN 2
#define SENSOR A0
byte val;

void setup() 
{
  pinMode(SENSOR,INPUT);
  pinMode(RED,OUTPUT);
  pinMode(GREEN,OUTPUT);
  pinMode(BLUE,OUTPUT);
  
  lcd.begin(16, 2);
  lcd.setCursor(0,0);
  lcd.print("Data:");
}

void loop() 
{
  val = map(analogRead(A0),306,756,0,100);
   lcd.setCursor(5,0);
   lcd.print(val);
    if(val >= 10)lcd.setCursor(7,0);
    else lcd.setCursor(6,0);
     lcd.print("/100 ");
  
 lcd.setCursor(6,1);
    if(val < 33) 
     { 
      digitalWrite(GREEN,1);
      digitalWrite(BLUE,0); 
      digitalWrite(RED,0); 
       noTone(BUZZER); 
        lcd.print("acceptable");
     }
      else if(val < 66)
       { 
        digitalWrite(GREEN,1);
        digitalWrite(BLUE,0); 
        digitalWrite(RED,1); 
         noTone(BUZZER); 
          lcd.print("  exceeded");
       }
        else
         {
          digitalWrite(GREEN,0); 
          digitalWrite(BLUE,0);
          digitalWrite(RED,1);
           tone(BUZZER,300);
            lcd.print(" dangerous");
         }
  delay(500);
}

Start Simulation