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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.

Transmissive optical sensor without aperture Vishay TCST1000/TCST2000 by Diana Fernandez
Demonstrates how to use a transmisive optical sensor. This sensor is used in mechanisms to detect when the gap in the top is blocked by an object. When the sensor detects an interruption the Wiring onboard LED is turned on.

    int sensorSwitch = 9;  // digital pin to attach the switch
    int sensorLED = 8;     // sensor LED
    int boardLED = WLED;   // Wiring onboard LED

    void setup()
    {
      pinMode(sensorSwitch, INPUT);   // sets digital pin 1 as input
      pinMode(sensorLED, OUTPUT);     // sets digital pin 0 as output
      pinMode(boardLED, OUTPUT);      // sets on-board LED digital pin as output
      digitalWrite(sensorLED, HIGH);  // turns ON the sensor LED
    }

    void loop()
    {
      // make the onboard LED to show the sensor status
      digitalWrite(boardLED, digitalRead(sensorSwitch));
    }