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| // Pin 13 has an LED connected on most Arduino boards.
// give it a name:
int pingPin = 9;
int inPin = 8;
// the setup routine runs once when you press reset:
void setup() {
// initialize the digital pin as an output.
Serial.begin(9600);
}
// the loop routine runs over and over again forever:
void loop() {
long duration, cm;
pinMode(pingPin, OUTPUT);
digitalWrite(pingPin, LOW);
delayMicroseconds(2);
digitalWrite(pingPin, HIGH);
delayMicroseconds(10);
digitalWrite(pingPin, LOW); // wait for a second
pinMode(inPin, INPUT);
duration = pulseIn(inPin, HIGH);
cm = microsecondsToCentimeters(duration);
Serial.print("distance=");
Serial.println(cm);
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 *0.034 / 2; |
