how to Change type control by button out of map

Hi.There

we know by using code like this :

map.addControl(new GSmallMapControl());
map.addControl(new GMapTypeControl());

to control map/satellite type change in the area of map, if I put a
button out of map.and create a map object,how can I change
map/satellite/.... state by button click ?

tkx.

Roger