#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 < 250 && jarak > 20){

  tone(pinbuz, 400);
  delay(100);
  noTone(pinbuz);
  delay(200);  
}
if (jarak < 200 && jarak > 150){

  tone(pinbuz, 400);
  delay(100);
  noTone(pinbuz);
  delay(200);  
}



else {
  noTone (pinbuz);

}
}