//echo $iif($dll(moo.dll,interfaceinfo,_),$v1,no connection detected)
^
Use that if the $dll() comes back with nothing when its not connected
or (if the above dont work)
//echo $iif($dll(moo.dll,interfaceinfo,_) != false,$v1,no connection detected)
^
Use that if the $dll() comes back with "false" when its not connected, replace "false" with what ever it comes back with when not connected