text: <!-- Copyright (c) 2013-2014 Texas Instruments Incorporated.  All rights reserved. -->
  
  window.onload = function()
  {
      document.getElementById('about').onclick = loadAbout;
      document.getElementById('overview').onclick = loadOverview;
      document.getElementById('block').onclick = loadBlock;
  
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  function loadAbout()
  {
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      return false;
  }
  
  function loadOverview()
  {
      loadPage("overview.htm");
      return false;
  }
  
  function loadBlock()
  {
      loadPage("block.htm");
      return false;
  }
  
  function loadPage(page)
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          xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
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      xmlhttp.open("GET", page, true);
      xmlhttp.setRequestHeader("Content-type",
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      xmlhttp.onreadystatechange = function ()
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