#include <Wire.h>
#include <LiquidCrystal_I2C.h>
LiquidCrystal_I2C lcd (0x27,16,2);

const int trigger = 9;
const int echo = 10;
const int led_merah = 13;
const int led_kuning = 12;
const int led_hijau = 11;



void setup() {
  lcd.init();
  lcd.backlight();
  pinMode (trigger,OUTPUT);
  pinMode (echo,INPUT);
  pinMode (led_merah, OUTPUT);
  pinMode (led_kuning, OUTPUT);
  pinMode (led_hijau,OUTPUT);
}

void loop() {
 digitalWrite(trigger,LOW);
 delayMicroseconds(5);
 digitalWrite(trigger, HIGH);
 delayMicroseconds(13);
 digitalWrite(trigger, LOW);

 long duration = pulseIn(echo, HIGH);
 long distance = (duration * 0.0343) /2;
 Serial.print("Sensor Distance");
 Serial.println(distance);

 if(distance <= 100){
  lcd.clear();
   digitalWrite(led_merah, HIGH);
   digitalWrite(led_kuning,LOW);
   digitalWrite(led_hijau, LOW);

   lcd.setCursor(0,0);
   lcd.print("JARAK: ");
   lcd.setCursor (7,0);
   lcd.print (distance);
   lcd.setCursor(10,0);
   lcd.print ("CM");
    delay(500);
 }
  if(distance>100&&distance<200){
    lcd.clear();
  digitalWrite(led_merah, LOW); 
  digitalWrite(led_kuning, HIGH);
  digitalWrite(led_hijau, LOW);

  lcd.setCursor(0,0);
  lcd.print("JARAK: ");
  lcd.setCursor (7,0);
  lcd.print (distance);
  lcd.setCursor(11,0);
  lcd.print("CM");
  delay(500);
  }
  if(distance >= 200) {
    lcd.clear();
    digitalWrite(led_merah, LOW);
    digitalWrite(led_kuning,LOW);
    digitalWrite(led_hijau, HIGH);
    lcd.setCursor(0,0);
    lcd.print("JARAK: ");
    lcd.setCursor (7,0);
    lcd.print (distance);
    lcd.setCursor(11,0);
    lcd.print("CM");
    delay(500);
  }
  }