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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.

SRF04/SRF05 Devantech Ultrasonic Ranger Finder by BARRAGAN http://barraganstudio.com
Demonstrates reading data from the Devantech Utrasonic Rangers SFR04/SFR05

    int echoPin = 9;  // digital pin to receive echo pulse
    int triggerPin = 8;  // digital pin to send trigger pulse
    unsigned long distance = 0;

    void setup()
    {
      pinMode(echoPin, INPUT);
      pinMode(triggerPin, OUTPUT);
    }

    void loop()
    {
      digitalWrite(triggerPin, HIGH); // set HIGH for 15us to trigger ranging
      delayMicroseconds(15);
      digitalWrite(triggerPin, LOW);  // set pin LOW
      distance = pulseIn(echoPin, HIGH);  // read in pulse length
      distance = distance / 58; // calculate distance from pulse length
      Serial.println(distance, DEC);
      delay(50);  // wait 50ms for next ranging
    }