Specifications

X723-300151 3-1 Issue 2
3 Dual Line Interface Unit
3.1 General
Dual Line Interface Units (DTE241) installed in ports 1 and 2 must be
fitted with DT986/2 or later firmware. When fitted to port 1 or port 2, the
configuration of the Dual LIU is transparent to the user.
The Dual LIU will be listed as a DT310 (base card) in the Equipment map.
The Dual LIU provides an interface to two 2048kbit/s PCM streams. The
PCM electrical signals comply to CCITT recommendation G.703 as either
unbalanced 75 ohm or balanced 120 ohm interfaces. The options of 75
ohms or 120 ohms operation is provided by a choice of I/O adaptor (DT315
and DT316 respectively) which is used exclusively with the DT310 card.
No other 3000 Series I/O adapter must be used as they may result in
damage to the DT310. The Dual LIU also provides an interface to a
2048kHz clock signal, the electrical characteristics of this also comply
with CCITT G.703.
When fitted in ports 3 or 4 the Dual LIU operates as a 'Smart' card which
is covered separately in the operation manual X723-303051 for the Dual
Line Interface Unit and not in this manual.
3.1.1 TS0 'Not Frame Word' Routing
Dual LIU cards fitted with firmware DT986/6 or later have the facility to
connect the TS0 'Not Frame alignment Word' to the cross-connect switch
for routing through the system or to the management patchfield. The
following modes of operation are provided, and these are selected when
configuring the mode of operation for the card in ports 1 and 2.
Modes 2,3,4,6 and 7 of this option require the installation of management
patchfield DT995/E in the Dual LIU to gain access to the Remote Alarm
bit 3.
Not frame words which are dropped/inserted to port (P1, P2, P3, P4)
streams timeslots 0 and 1 may be cross connected to any other timeslots
using the normal cross connect facilities of the multiplexer.