var scrolling = 'started';    

function stopstart()
{
    if (scrolling == 'started') 
    {
        eventscroll.stop();
        scrolling = 'stopped';
    } else {
        eventscroll.start();
        scrolling = 'started';
    }
}

function startagain()
{
    if(scrolling=='stopped')
    {
        eventscroll.start();
        scrolling = 'started';
    }
}