#define trg 4
#define echo 5
int pinled = 6;
int pinrelay = 2;
void setup() {
  // put your setup code here, to run once:
  Serial.begin(115200);
  pinMode(trg, OUTPUT);
  pinMode(echo, INPUT);
  pinMode(pinled, OUTPUT);
  pinMode(pinrelay, OUTPUT);
}

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

  int del = pulseIn(echo, HIGH);
  Serial.print("Jarak Dalam cm = "); //in inch duration/148
  Serial.println(del/58);
  delay(1000);
  if(echo<100){
    digitalWrite(pinrelay, HIGH);
    delay(100);
  }
  else{
    digitalWrite(pinrelay, LOW);
    delay(100);
  }
}