In the latest 11.1.3 release you can switch between softphone and hardphone while in older releases you have to park the call and pick it up again.
So in your case you would program a button and shortcode to park the call then the same to unpark the call again.
Softphone doesn't have the button convenience to pick up a call.
I usually have park 101 (if there are no 100 range extensions)
101
Unpark call
101
and
*101
Park call
101
that way all you have to dial to pick it up is 101 and to park it you transfer to *101
Joe
FHandw, ACSS, ACIS