#define echoPin 2
#define trigPin 3          
                                                                                                                                                                                               
int maximumRange = 300;
int minimumRange  = 00;                
long duration, distance;                  

void setup() {
  // put your setup code here, to run once:                                
  Serial.begin (9600);           
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);
  pinMode(9, OUTPUT);
  pinMode (10, OUTPUT );
  pinMode (11, OUTPUT); 
}

void loop() {       
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);           
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);
  duration = pulseIn(echoPin, HIGH);          

  //perhitungan untuk di jadikan jarak 
  distance = duration/58,2;
                                                                                                                                                                  
  /*jika jarak melebihi 300 cm, 
  kirim keterangan "di luar jangkauan"*/

  if (distance >= maximumRange || distance <= minimumRange){
  Serial.println("di luar jangkauan ");
  }
  else{

  /*
  kirim hasil pembacaan jarak melalui serial monitor
  */
  Serial.print("JARAK :   ");
  Serial.print(distance);
  Serial.println(" cm");

  delay(1000);
  }
  if (distance <=100 ){
  digitalWrite(11, HIGH );
  digitalWrite(10 , LOW );
  digitalWrite(9, LOW );
}
}