//PROGRAM INDIKATOR JARAK RIAN NURCAHYA 
#define trigPin 7
#define echoPin 6
#define led 13
#define led2 12
#define led3 11
#define buzzer 8
int sound = 250;
void setup() {
 Serial.begin (9600);
 pinMode(trigPin, OUTPUT);
 pinMode(echoPin, INPUT);
 pinMode(led, OUTPUT);
 pinMode(led2, OUTPUT);
 pinMode(led3, OUTPUT);
 pinMode(buzzer, OUTPUT);
}
void loop() {
 long duration, distance;
 digitalWrite(trigPin, LOW);
 delayMicroseconds(2);
 digitalWrite(trigPin, HIGH);
 delayMicroseconds(10);
 digitalWrite(trigPin, LOW);
 duration = pulseIn(echoPin, HIGH);
 distance = (duration/2) / 29.1;
 if (distance <= 300) {
 digitalWrite(led, HIGH);
 sound = 250;
}
 else {
 digitalWrite(led,LOW);
 }
 if (distance < 200) {
 digitalWrite(led2, HIGH);
 sound = 260;
}
 else {
 digitalWrite(led2, LOW);
 }
 if (distance < 100) {
 digitalWrite(led3, HIGH);
 sound = 270;
}
else {
 digitalWrite(led3, LOW);
 }
 
 if (distance > 300 || distance <= 0){
 Serial.println("Jarak diluar jangkauan!");
 noTone(buzzer);
 }
 else {
 Serial.print(distance);
 Serial.println(" cm");
 tone(buzzer, sound);
 }
 delay(500);
}