#include <Servo.h>
Servo myservo;
long jarak;
long waktu;

void setup() {
  pinMode(2,OUTPUT);
  pinMode(1, INPUT);
  Serial.begin(115200);
  myservo.attach(11);
}

void loop() {
  digitalWrite(2,LOW);
  delayMicroseconds(2);
  digitalWrite(2,HIGH);
  delayMicroseconds(10);
  digitalWrite(2,HIGH);

  waktu=pulseIn(1,HIGH);
  jarak=0.034/2*waktu;

  if(jarak<20){
    myservo.write(180);
    delay(500);
  if(jarak>20){
    myservo.write(0);
    delay(500);
  }}
  if(jarak>0){
    myservo.write(0);
    delay(500);
  }
  Serial.println(jarak);
}