var THE_ScrollSpeed = 4;
var THE_ScrollFrequency = 30;
var THE_ScrollSpaceAllowance = 100;

function Scroller_Down(_ContentName){
	var _Content = document.getElementById(_ContentName);
	var _x = parseInt(_Content.style.top);
	var _h = _Content.offsetHeight;
	var _t = (_h + _x) > THE_ScrollSpaceAllowance;
	//change position
	if (_t) _Content.style.top = (_x - THE_ScrollSpeed) + "px";
	//set up timer
	window['timer_Scroller_Down_' + _ContentName] = setTimeout("Scroller_Down('" + _ContentName + "')", THE_ScrollFrequency);
}

function Scroller_Up(_ContentName){
	var _Content = document.getElementById(_ContentName);
	var _x = parseInt(_Content.style.top);
	//change position
	if (_x < 0) _Content.style.top = (_x + THE_ScrollSpeed) + "px";
	//set up timer
	window['timer_Scroller_Up_' + _ContentName] = setTimeout("Scroller_Up('" + _ContentName + "')", THE_ScrollFrequency);
}
function Scroller_Clear(_ContentName){
	//clear all timers
	clearTimeout(window['timer_Scroller_Up_' + _ContentName]);
	clearTimeout(window['timer_Scroller_Down_' + _ContentName]);
}
function Scroll_Init(_ContentName){
	var _Content = document.getElementById(_ContentName);
	_Content.style.position = "absolute";
	_Content.style.left = "0px";
	_Content.style.top = "0px";
	//_Content.style.width = "325px";
}