var _scroller_time;
var _scroler_controlName;
var _scroler_up;

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

function scrollControlUp(name) {
    _scroler_up = true;
    _scroler_controlName = name;
    
    scrollControl();
}

function scrollControlDown(name) {
    _scroler_up = false;
    _scroler_controlName = name;
    
    scrollControl();
}

function scrollControl() {
    var BY_PX = 10;
    if (!_scroler_up) {
        document.getElementById(_scroler_controlName).scrollTop = document.getElementById(_scroler_controlName).scrollTop + BY_PX;
    }
    else {
        document.getElementById(_scroler_controlName).scrollTop = document.getElementById(_scroler_controlName).scrollTop - BY_PX;
    }
    
    _scroller_time = setTimeout('scrollControl()', 100);   
}

function _scrollTop(name) {
    stopScroll();
    document.getElementById(name).scrollTop = 0;        
}

function _scrollBottom(name) {
    stopScroll();
    document.getElementById(name).scrollTop = 10000;        
}