Vertical Communications 8412S - Manual (Page 112)

10.3 Operating Your Telephone
With A DSS/BLF Console
The IB48X, and IB24X DSS/BLF consoles have additional buttons and
status lights that extend the memory button capability of an adjacent
companion telephone. The buttons can be programmed for automatic
dialing (speed dial) or direct station selection (DSS) with busy lamp field
(BLF) using the instructions provided previously in this guide.
When the installer assigns a DSS/BLF console to a station port, the
system recognizes it as such and automatically clears (blanks) the
console buttons so that you can store numbers at the buttons as you need
them.
10 – 6 Large Screen Speakerphone Manual
Using The Attendant Features GCA70–349
Level access buttons
IB48X DSS/BLF Console
Level access buttons
IB24X DSS/BLF Console