When the user activates an SCC key or soft-key, it is up to the Device Adapter to determine whether this is for programing or calling purposes. If done without selecting a line appearance, this is intended for programming. Otherwise, the user wants to use the list.

Speed dial programming requires the use of a call appearance to make a “programming” call. If no free call appearance button is available, the programming fails. It also means the programming can fail due to other call related reason.