// JavaScript Document
var scrollSpeed =0.5;   // number of pixels to change every frame
 var scrollDepth =165; // height of your display box
 var scrollHeight=0;   // this will hold the height of your content
 var scrollDelay=25;  // delay between movements.

 var scrollPos=scrollDepth; // current scroll position
 var scrollMov=scrollSpeed; // for stop&start of scroll

 function doScroll() {
  if(scrollHeight==0) { getHeight(); }
  scrollPos-=scrollMov;
  if(scrollPos< (0-scrollHeight)) { scrollPos=scrollDepth; }
  document.getElementById('scrollTxt').style.top=scrollPos+'px';
  setTimeout('doScroll();', scrollDelay);
 }

 function getHeight() {
  scrollHeight=document.getElementById('scrollTxt').offsetHeight;
 }

 function scrMove() { scrollMov=scrollSpeed; }
 function scrStop() { scrollMov=0; }