#define MQ2_ANA A1
#define MQ2_DIG 2
#define MQ3_ANA A2
#define MQ3_DIG 2
#define LEDMERAH 8
#define LEDKUNING 13
#define BUZER 7
#include <LiquidCrystal_I2C.h>
LiquidCrystal_I2C lcd(0x27, 20, 4);
void setup() {
  // put your setup code here, to run once:
  Serial.begin(9600);
  pinMode(MQ2_ANA, INPUT);
  pinMode(MQ2_DIG, INPUT);
  pinMode(LEDMERAH, OUTPUT);
  lcd.init();
  lcd.backlight();
}

void loop() {
  if(analogRead(MQ2_ANA) >200){
    digitalWrite(LEDMERAH, HIGH);
    delay(500);
    digitalWrite(LEDMERAH, LOW);
  }
  else{
    digitalWrite(LEDMERAH, LOW);
  }
  if(analogRead(MQ3_ANA) <200){
    digitalWrite(LEDKUNING, HIGH);
    delay(500);
    digitalWrite(LEDKUNING, LOW);
  }
  else{
    digitalWrite(LEDKUNING, LOW);
  }
  // put your main code here, to run repeatedly:
  Serial.print("Analog: ");
  Serial.println(analogRead(MQ2_ANA));
  Serial.print("Digital: ");
  Serial.println(digitalRead(MQ2_DIG));
  delay(1000);
  lcd.setCursor(1, 0);
  lcd.print("Analog =");
  lcd.print(MQ2_ANA);
  lcd.setCursor(1, 1);
  lcd.print("Digital =");
  lcd.print(MQ2_DIG);
  //digitalWrite(LEDMERAH, HIGH);
  //digitalWrite(BUZER, HIGH);
  //delay(300);
  //digitalWrite(LEDMERAH, LOW);
  //delay(300);
  //digitalWrite(LEDMERAH, HIGH);
 }