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This example is for Wiring version 0024+. 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.

Port and LEDs by BARRAGAN http://barraganstudio.com
Ports are sets of 8 pins which can be used to send data in parallel to devices like printers or displays. This example demonstrates the use of digital ports to turn on 8 LEDs connected to digital port 0, the LEDs will reflect the bit value of each pin, value 0 will be 00000000 or all LEDs turned OFF, value 255 will be 11111111 or all LEDs turned ON.

    int port = 0;               // which port will be used
    byte value = 0;             // byte will go from 0 to 255

    void setup()
    {
      portMode(port, OUTPUT);
      Serial.begin(9600);       // use serial to monitor value
    }

    void loop()
    {
      portWrite(port, value);   // writes the value to port 0
      value = value + 1;        // increment the variable
      Serial.println(value, DEC);  // print value to console for monitoring
      delay(200);               // waits for 200 milli seconds
    }