#define pinTrig 3
#define pinEcho 2
#define pinBuz 13

long waktu, jarak;

void setup() {
  // put your setup code here, to run once:
Serial.begin(9600);
pinMode (pinBuz, OUTPUT);
pinMode (pinTrig, OUTPUT);
pinMode (pinEcho, INPUT);
}

void loop() {
  // put your main code here, to run repeatedly:
digitalWrite (pinTrig, LOW);
delayMicroseconds (2);
digitalWrite (pinTrig, HIGH);
delayMicroseconds (10);
digitalWrite(pinTrig, LOW);

waktu = pulseIn(pinEcho, HIGH);
jarak = waktu / 58,2;

if (jarak < 200 && jarak >= 150){
  tone(pinBuz, 200);
  delay (50);
  noTone (pinBuz);
  delay (100);
}
if (jarak < 150 && jarak >= 50){
  tone(pinBuz, 300);
  delay (50);
  noTone (pinBuz);
  delay (50);
}
if (jarak < 150 && jarak >= 2){
  tone(pinBuz, 400);
  delay (50);
  noTone (pinBuz);
}
else {
  noTone (pinBuz);
}
}