var thespeed=3 //Enter scroll speed in integer (Advised: 1-3)
var myspeed=0;

function scrollwindow() {
	window.scrollBy(0,myspeed)
}

function initializeIT(){
	if (myspeed!=0) {
		scrollwindow()
	}
}

if (document.all||document.getElementById||document.layers)
setInterval("initializeIT()",20)

function scrollarriba() {
	myspeed=-thespeed;
}
function scrollparar() {
	myspeed=0;
}
function scrollabajo() {
	myspeed=thespeed;
}