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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.

74LS595 Shift Register by BARRAGAN http://barraganstudio.com
Sends the value stored in the byte variable counter to the shift register. The shift register outputs QA to QH will reflect the value sent.

    int data = 8;      // Wiring pin 8 for data
    int clock = 9;     // Wiring pin 9 for clock
    int strobe = 10;   // Wiring pin 10 for the strobe (latch)
    byte counter = 0;

    void setup()
    {
      pinMode(data, OUTPUT);
      pinMode(clock, OUTPUT);
      pinMode(strobe, OUTPUT);
    }

    void loop()
    {
      shiftOut(data, clock, LSBFIRST, counter);  // writes counter to the shift register
      digitalWrite(strobe, HIGH);
      delay(1);  // or even delayMicroseconds(50);
      digitalWrite(strobe, LOW);
      delay(1000);
      counter = counter + 1;
    }