Nortel Networks P0857846 - Manual (Page 156)

General System features / 143
P0857846 Issue 02 Norstar-PLUS Modular ICS 2.0 System Coordinator Guide
Memory buttons
Memory buttons are the buttons with indicators on the M7208,
M7310, and M7324 telephones, and the dual buttons without
indicators on the M7310 telephone. There is also a single memory
button, without an indicator, on the M7100 telephone. Memory
buttons can be used as answer, autodial, line, incoming line group,
and programmed feature buttons. Line, incoming line group,
intercom and answer buttons must have indicators.
One-line display
The M7100 and M7208 telephones have a one-line display. Other
Norstar telephones have a second line on the display which shows
the functions of the three buttons directly below it.
Some display buttons, such as TRANSFER and ALL , are simply
shortcuts which are not available on a one-line display.