<!--
   numImages = 7;
   rpiImages = new Array((numImages*2))
   for(i = 1; i <= 7; i++)
      {
      rpiImages[i] = new Image();
      rpiImages[i+numImages] = new Image();
      rpiImages[i].src = "images/nav"+i+".jpg";
      rpiImages[i+numImages].src = "images/nav"+i+"_hover.jpg";
      }
 function on_image(loc, img)
        {
                img+=numImages;
                document.images[loc].src=rpiImages[img].src;
        }
function off_image(loc, img) 
        {
                document.images[loc].src=rpiImages[img].src;
        }
//-->