AT&T MERLIN LEGEND Release 2.0 Equipment And Operations Manual page 53

Introduction
Tie trunks
Ground-start trunks (only if not registered as KF and not strapped for
Key mode)
The direct outside trunks must be terminated on individual telephones and must
appear on the telephones' line buttons. For example, if tie trunks are assigned
to buttons on telephones 1 and 2, the buttons on those telephones appear as
shown in Figure 1-8.
Figure 1-8. Labeled Line Buttons for Behind Switch Telephones
The bottom button on each telephone is reserved for the Prime Line from the
host system. The outside lines appear on the labeled line buttons above the
Prime Line. In Figure 1-8, the first line (5678) is assigned to buttons on both
telephones, and the second (5679) is assigned to a button only on the second
telephone.
The following features are not available in Behind Switch mode:
Trunk pools
A R S
Q C C
SA buttons
Telephone # 2
Modes of Operation 1-25