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              <p>Move your mouse left and right at different speeds.</p>
<div id="slider_input" class="slider">
  <div class="slider_indicator"></div>
<p id="output"></p>
              html {
  background-color: #CC6633;
  font-family: "Fira Mono",Monaco,"Andale Mono","Lucida Console","Bitstream Vera Sans Mono","Courier";
  user-select: none;
  -moz-user-select: none;
  -khtml-user-select: none;
  -webkit-user-select: none;
  -o-user-select: none;

.slider {
  margin: 10px;
  width: 400px;
  height: 16px;
  background: rgba(0,0,0,.3);
  position: relative;

.slider_indicator {
  width: 16px;
  height: 16px;
  background: #000;
  position: absolute;
// scroll to bottom to see responsiveAnalogRead() function

// consts for demo
var SLIDER_WIDTH = 400;
var NOISE = 0.003;

// vars for demo
var mouseX = 0;

// set up HTML elements and JS events for demo

var output = $('#output');
var sliderIndicatorInput = $('#slider_input > div');

var updateSlider = function(slider, value) {
  var sliderLeft = value / (ANALOG_RESOLUTION - 1) * SLIDER_WIDTH - 8;
  slider.css('left', sliderLeft+'px');

var begin = function() {
  var loop = function() {
    var newValue = analogRead();

    // update sliders
    updateSlider(sliderIndicatorInput, newValue);

    // output status
    var outputText = "analogRead: " + newValue;

  // event handlers
  $(window).mousemove(function( event ) {
    mouseX = event.pageX;

  // begin loop

// Define fake Arduino millis() and analogRead() functions

var millis = function() {
  var d = new Date();
  return d.getTime(); 

var analogRead = function() {
  // get input from 0 - 1
  var input = Math.max(0,Math.min(mouseX - 10,SLIDER_WIDTH)) / SLIDER_WIDTH;
  // add noise to input
  input += (Math.random() - 0.5) * 2 * NOISE;
  input = Math.max(0, Math.min(1, input));
  // simulate analog read
  return Math.floor(input * (ANALOG_RESOLUTION - 1));

// begin demo

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