TabUI - Access parent form values from a tabUI page?

TabUI - Access parent form values from a tabUI page?

I have a page which uses TabUI. Each tab is a separate page e.g

<div id="tabs">
         <ul>
            <li><a href="settings.html"><span>Settings</span></a></li>
            <li><a href="data.html"><span>Data</span></a></li>
            <li><a href="misc.html"><span>Misc</span></a></li>
         </ul>
      </div>


How do I access a form control value e.g a text box on the parent page from within the settings.html or other tab pages?