var milliseconds = 7000;
var nBtn = 4;
var mi=2;
var int;
var old=1;
var prev = nBtn;

function rotate(spec, NextDiv){
	if(spec!=null){
		mi=spec;
		if(NextDiv!=null){
			mi = spec + 1;
		};
		control(0);
	};
	
	if(old!=-1){document.getElementById('m' + old).style.display = 'none';
	}else{
	document.getElementById('m1').style.display = 'none';
	document.getElementById('b1').style.backgroundColor = '#999999';	
	}
	
	var mDiv = 'm' + mi;
	milliseconds = 4000;
	
	document.getElementById(mDiv).style.display = 'block';
	document.getElementById('b1').style.backgroundColor = '#DAD9D6';
	document.getElementById('b' + prev).style.backgroundColor = '#DAD9D6';
	document.getElementById('b' + mi).style.backgroundColor = '#999999';
	
	old=mi;
	
	/* make the main div transpartent */
	changeOpac(0, mDiv);
	
    var timer = 0;
	var speed = Math.round(500 / 100); 
	
	/*fade in our main div*/
    for(x = 0; x <= 100; x++) { 
        setTimeout("changeOpac(" + x + ",'m" + mi + "')",(timer * speed)); 
        timer++; 
    }
	
	mi++;
	prev = mi - 1;
	
	if(prev<1){
	prev = nBtn;
	}
	if(mi>nBtn){
	mi=1;
	}
};

function changeOpac(opacity, id) { 
var object = document.getElementById(id).style; 
object.opacity = (opacity / 100); 
object.MozOpacity = (opacity / 100); 
object.KhtmlOpacity = (opacity / 100); 
object.filter = "alpha(opacity=" + opacity + ")"; 
}

function control(op){
	if(!op){
		document.getElementById('stop').style.display = 'none';
		document.getElementById('play').style.display = 'inline';
		clearInterval(int);
	}
	else{
		document.getElementById('stop').style.display = 'inline';
		document.getElementById('play').style.display = 'none';
		document.getElementById('b1').style.backgroundColor = '#999999';
		int = setInterval('rotate()', milliseconds);
	}
}