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This example is for Wiring version 1.0 build 0100+. If you have a previous version, use the examples included with your software. If you see any errors or have comments, please let us know.

Parallax PING Sensor by BARRAGAN http://barraganstudio.com
Demonstrates use of the pulseIn command to read data from the Parallax PING Sensor

    int signalPin = 8;     // sensor signal pin connected to wiring pin 0
    long elapsedtime = 0;

    void setup()
    {
      Serial.begin(9600);
    }

    void loop()
    {
      elapsedtime = 0;
      pinMode(signalPin, OUTPUT);  // set signalPin as OUTPUT

      // Send 0-1-0 pulse to activate the sensor
      digitalWrite(signalPin, LOW);
      delayMicroseconds(2);
      digitalWrite(signalPin, HIGH);
      delayMicroseconds(5);
      digitalWrite(signalPin, LOW);

      // Listen to pulse
      pinMode(signalPin, INPUT);               // set signalPin as INPUT
      elapsedtime = pulseIn(signalPin, HIGH);  // get the length of the pusle while it is HIGH

      // print value through Serial

      Serial.println(elapsedtime, DEC);
      delay(100);
    }