shiftOut in javascript

gistfile1.js

var five = require("johnny-five"),
    board;

board = new five.Board();

board.on("ready", function() {
  (new five.Led(13)).on();

  var dataPin =   2;
  var clockPin =  3;
  var latchPin =  4;
  var value =     0;

  next(value);

  function next(i) {
    board.digitalWrite(latchPin, board.firmata.LOW);

    shiftOut(dataPin, clockPin, i);

    board.digitalWrite(latchPin, board.firmata.HIGH);

    if (++i > 255) {
      return;
    }

    setTimeout(function() {
      next(i);
    }, 500);
  }

  function shiftOut(dataPin, clockPin, value) {
    // much thanks to http://www.sqlskills.com/blogs/paulselec/post/Arduino-figuring-out-shift-registers.aspx
    for (var mask = 128; mask > 0; mask = mask >> 1) {
      board.digitalWrite(clockPin, board.firmata.LOW);

      board.digitalWrite(
        dataPin, board.firmata[ value & mask ? 'HIGH' : 'LOW' ]
      );

      board.digitalWrite(clockPin, board.firmata.HIGH)
    }
  }
});

Video: https://vimeo.com/46463390

Johnny Five: https://github.com/rwldrn/johnny-five

(In fairness, I'm not using that much of Johnny Five for this particular program, but it's been a godsend for all my other Arduino exploits so far.)

The serial/usb detection still counts ;)

I knew it was good for something ;)

Here is my quick hack to control on-off LEDs with Express + Socket.IO + Johnny Five

https://plus.google.com/102455075182037186148/posts/JkbhQG8Mrkg (video)

Nice!