var no_of_banner=6;
var banner_h=75;
var banner_mh=banner_h*no_of_banner;
var banner_y=0;
var banner_t=5000;
var banner_scrollevent;

function scrollBanner() {
    document.getElementById('bannerDiv').style.top=banner_y+'px';
    banner_y -= banner_h;
    if(banner_y <= -banner_mh) {
	 banner_y = 0;
    }
    banner_scrollevent = setTimeout('scrollBanner()',banner_t);
}

function stopscroll(){
    clearTimeout(banner_scrollevent)
}

function restartscroll(){
    banner_scrollevent = setTimeout('scrollBanner()',banner_t);
}

function previousBanner(){
    clearTimeout(banner_scrollevent);
    banner_y += banner_h;
    if (banner_y > 0){
	banner_y = banner_h - banner_mh;
    }
    banner_y += banner_h;
    if (banner_y > 0){
	banner_y = banner_h - banner_mh;
    }
    scrollBanner();
}

function nextBanner(){
    clearTimeout(banner_scrollevent);
    scrollBanner();
}

window.onload=function() {
    scrollBanner();
}