sketch_arduino

//  led
byte red = 13;
byte yellow = 12;
byte green = 11;
// buzzer
byte buzzer = 10;
// hc-SR04
#define pingPin 7
long duration, distance;
// monitor
#include <Wire.h>
#include <LiquidCrystal_I2C.h>
LiquidCrystal_I2C lcd(0x3f,16,2);


void setup() {
  // initialize the LCD
  lcd.begin();

  // Turn on the blacklight and print a message.
  lcd.backlight();
  lcd.setCursor(1,0);
  lcd.print("Program Arduino");
  lcd.setCursor(2,1);
  lcd.print("Sensor Jarak");
  delay(30000);

  // put your setup code here, to run once:
  Serial.begin(9600);
  // led
  pinMode(red, OUTPUT);
  pinMode(yellow, OUTPUT);
  pinMode(green, OUTPUT);
  // buzzer
  pinMode(buzzer, OUTPUT);

}

void loop() {
  // put your main code here, to run repeatedly:
  // hc-SR04
  duration = 0;
  distance = 0;
  pinMode(pingPin, OUTPUT);
  digitalWrite(pingPin, LOW);
  delayMicroseconds(2);
  digitalWrite(pingPin, HIGH);
  delayMicroseconds(5);
  digitalWrite(pingPin, LOW);
  pinMode(pingPin, INPUT);
  duration = pulseIn(pingPin, HIGH);
  distance = duration/29/2;
  Serial.print(distance);
  Serial.print("cm");
  Serial.println();
  delay(100);

  // Turn on the blacklight and print a message.
  lcd.backlight();
  lcd.setCursor(0,0);
  lcd.print("jarak = ");
  lcd.print(distance);
  lcd.print(" cm   ");
  Serial.println();
  lcd.setCursor(0,1);
  lcd.print("Aman!          ");
  lcd.backlight();
  lcd.setCursor(0,0);
  lcd.print("jarak = ");
  lcd.print(distance);
  lcd.print(" cm   ");
  Serial.println();
  lcd.setCursor(0,1);
  lcd.print("Hati-hati!      ");
  digitalWrite(green, HIGH);
  delay(1000);
  digitalWrite(green, LOW);
  lcd.backlight();
  lcd.setCursor(0,0);
  lcd.print("jarak = ");
  lcd.print(distance);
  lcd.print(" cm   ");
  Serial.println();
  lcd.setCursor(0,1);
  lcd.print("Waspada!      ");
  digitalWrite(yellow, HIGH);
  delay(1000);
  digitalWrite(yellow, LOW);
  lcd.backlight();
  lcd.setCursor(0,0);
  lcd.print("jarak = ");
  lcd.print(distance);
  lcd.print(" cm      ");
  Serial.println();
  lcd.setCursor(0,1);
  lcd.print("Bahaya!         ");
  digitalWrite(red, HIGH);
  digitalWrite(buzzer, HIGH);
  delay(500);
  digitalWrite(red, LOW);
  digitalWrite(buzzer, LOW);
  delay(500);
}