var timer_id;
var frm;

function scroll_iframe(inc) {
	frm = 'scr1';
  if (timer_id) clearTimeout(timer_id);
  if (window.frames[frm]) {
   window.frames[frm].scrollBy(0, inc);
       timer_id = setTimeout("scroll_iframe(" + inc + ")", 20);
  }
}

function stopScroll() { if (timer_id) clearTimeout(timer_id); }