const int pingPin = 13; int inPin = 12; void setup() { Serial.begin(9600); } void loop() { long duration, cm; pinMode(pingPin, OUTPUT); digitalWrite(pingPin, LOW); delayMicroseconds(2); digitalWrite(pingPin, HIGH); delayMicroseconds(5); digitalWrite(pingPin, LOW); pinMode(inPin, INPUT); duration = pulseIn(inPin, HIGH); cm = microsecondsToCentimeters(duration); Serial.print(cm); Serial.print("cm"); Serial.println(); delay(100); } long microsecondsToCentimeters(long microseconds) { // The speed of sound is 340 m/s or 29 microseconds per centimeter. // The ping travels out and back, so to find the distance of the // object we take half of the distance travelled. return microseconds / 29 / 2; }
