var index=1;
var preEn="/SiteCollectionImages/Pag_Up_Arrow_2.gif";
var preDis="/SiteCollectionImages/Pag_Up_Arrow_1.gif";
var nextEn="/SiteCollectionImages/Pag_Down_Arrow_2.gif";
var nextDis="/SiteCollectionImages/Pag_Down_Arrow_1.gif";

function upClick(itemCount,obj)
{
	if(index==1)
		return;
		
	index--;
	
	window.api = jQuery("#slider1").scrollable();
	api.prevPage();
	
	if(index==1)
	{
		obj.disabled=true;
		obj.setAttribute('src',preDis);
	}
	
	if(index!=itemCount)
	{
		var btnNext=document.getElementById('ibtnDown');
			btnNext.disabled=false;
			btnNext.setAttribute('src',nextEn);
	}
}

function downClick(itemCount,obj)
{
	if(index>=itemCount)
		return;

	index++;

  window.api = jQuery("#slider1").scrollable();
	api.nextPage();
  
	if(index==itemCount)
	{
		obj.disabled=true;
		obj.setAttribute('src',nextDis);
	}
	
	if(index!=1)
	{
		var btnPre=document.getElementById('ibtnUp');
		btnPre.disabled=false;
		btnPre.setAttribute('src',preEn);
	}
}