var speed = 1;

function moveDown(objName, height)
{
	var crossobj = document.getElementById(objName);
	var top = ( parseInt(crossobj.style.top) || 0 );
	if (window.moveupvar)
	{
		clearTimeout(moveupvar);
	}
	if (parseInt(top) >= ((crossobj.offsetHeight - height) * (-1)))
	{
		crossobj.style.top = top - speed + "px";
		crossobj.top -= speed;
		movedownvar = setTimeout("moveDown('" + objName + "', " + height + ")", 20)
	}
	if (parseInt(top) == ((crossobj.offsetHeight - height) * (-1)))
	{
		crossobj.style.top = 75 + "px";
	}
	
}
function moveUp(objName)
{
	var crossobj = document.getElementById(objName);
	var top = ( parseInt(crossobj.style.top) || 0 );
	if (window.movedownvar)
	{
		clearTimeout(movedownvar);
	}
	if (top <= 0)
	{
		crossobj.style.top = top + speed + "px"
		crossobj.top += speed
		moveupvar = setTimeout("moveUp('" + objName + "')", 20)
	}
}
function stopScroll()
{
	if (window.moveupvar)
	{
		clearTimeout(moveupvar);
	}
	if (window.movedownvar)
	{
		clearTimeout(movedownvar);
	}
}