Day2 04_sonic

• 초음파 센서를 이용한 거리 출력

const int trigPin = 14;  //A0

const int echoPin = 15;  //A1

const int ledPin = 13;

void setup() {

  // put your setup code here, to run once:

  pinMode(trigPin, OUTPUT);

  pinMode(echoPin, INPUT);

  pinMode(ledPin, OUTPUT);

  Serial.begin(9600);

}

void loop() {

  long distance = getDistance();

  Serial.println(String(distance) + " cm");

  if (distance < 15) {

    digitalWrite(ledPin, HIGH);

  } else {

    digitalWrite(ledPin, LOW);

  }

  // delay(100);

}

long getDistance() {

  // put your main code here, to run repeatedly:

  // trig - 10us

  digitalWrite(trigPin, LOW);

  delayMicroseconds(2);

  digitalWrite(trigPin, HIGH);

  delayMicroseconds(10);

  digitalWrite(trigPin, LOW);

  long duration = pulseIn(echoPin, HIGH);

  long distance = (duration / 2) / 29.1;

  return distance;

}