#define lampum 2
#define alarm 4
#include <Servo.h>
#define trigPin 13
#define echoPin 12
Servo myservo;


void setup() {
  // put your setup code here, to run once:
pinMode(lampum, OUTPUT);
pinMode(alarm, OUTPUT);
myservo.attach(5);
pinMode(trigPin, OUTPUT);
pinMode(echoPin, INPUT);

}

float readDistanceCM() {
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);
  int duration = pulseIn(echoPin, HIGH);
  return duration * 0.034 / 2;
}

void loop() {
  // put your main code here, to run repeatedly:
float distance = readDistanceCM();
  Serial.print("Palang Kereta Api: ");
  Serial.print(readDistanceCM());
  Serial.println();

  if (distance <= 50) {
    myservo.write(180);
    tone(alarm, 1000);
    digitalWrite(lampum, HIGH);
    delay (200);
    tone(alarm, 500);
    digitalWrite(lampum, LOW);
    delay(200);
  }
  else {
    myservo.write(0);
    noTone(alarm);
  }
}