Take two update panel
Now suppose updatepanel which will be updated on buttonclick is named as buttonupdatepanel.
and second updatepanel which will be updated on timerclick is named as timerupdatepanel.
For buttonupdatepanel take button1 in updatepanel
for timerupdatepanel click on timetick event and then write
timerupdatepanel.updatepanel();
Your panel will be updated at each intervals.