var timerId = 0;
var position = 70;

function scrollBanner (enabled) {
  if (enabled) {
    var banner = document.getElementById("banner");
    if (banner) {
      if (position > (-banner.offsetHeight))
        banner.style.top = position--;
      else
        position = 70;
      timerId = window.setTimeout("scrollBanner(true);", 50);
    }
  }
  else
    window.clearTimeout(timerId);
  return (true);
}