Nortel Networks 1100 Series - Manual (Page 15)

Introduction
15
Expansion Module, the IP Phone should be powered by AC global power supply
only.
Icons
The Expansion Module supports the same icons and cadences that
appear on the IP Phone line keys.
Icons on the display can flash at pre-defined intervals to indicate different
status. The flashing interval is defined by the IP Phone with the flashing
effect performed by the expansion module.