Ultra Sonic Sensor
//created by arduino demon #define echoPin 2 // attach pin D2 Arduino to pin Echo of HC-SR04 #define trigPin 3 //attach pin D3 Arduino to pin Trig of HC-SR04 // defines variables long duration; int distance; void setup() { pinMode(trigPin, OUTPUT); pinMode(echoPin, INPUT); Serial.begin(9600); Serial.println("Ultrasonic Sensor HC-SR04 Test"); Serial.println("with Arduino UNO R3"); } void loop() { digitalWrite(trigPin, LOW); delayMicroseconds(2); digitalWrite(trigPin, HIGH); delayMicroseconds(10); digitalWrite(trigPin, LOW); duration = pulseIn(echoPin, HIGH); distance = duration * 0.034 / 2; Serial.print("Distance: "); Serial.print(distance); Serial.println(" cm"); }