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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.

keyboard by Tom Igoe
Plays a pitch that changes based on a changing analog input circuit: 3 force-sensing resistors from +5V to analog in 0 through 5 3 10K resistors from analog in 0 through 5 to ground 8-ohm speaker on digital pin 8

    const int threshold = 10; // minimum reading of the sensors that generates a note

    // notes to play, corresponding to the 3 sensors:
    int notes[] = { NOTE_A4, NOTE_B4, NOTE_C3 };

    void setup()
    {
    }

    void loop()
    {
      for (int thisSensor = 0; thisSensor < 3; thisSensor++)
      {
        // get a sensor reading:
        int sensorReading = analogRead(thisSensor);

        // if the sensor is pressed hard enough:
        if (sensorReading > threshold)
        {
          // play the note corresponding to this sensor:
          tone(8, notes[thisSensor], 20);
        }
      }
      Serial.println();
    }