AVT Titan, Operator'S Manual

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C H A P T E R 3 : O P E R A T I O N W I T H A P C
During the transmission of data via an X.21 interface, the octet timing is
usually lost. A bit-search algorithm is used to synchronise with the byte format
of the data stream.
Some ISDN terminals do not have the bit-search algorithm capability. To ne-
vertheless set up connections with such equipment, the connection must be
synchronous with the ISDN-byte clock. For this, must be ensured that octet ti-
ming is provided transparently at the TITAN X.21 interfaces.
Note Set the OCTET TIMING switch to AVAILABLE only if the con-
nected Terminal Adapter remote end provides octet-timing
synchronous transmission.
3.3.8.8 E1 FORMAT
Two frame formats are available for the E1 network interface:
Warning The set frame format should be the same as the frame format
of the transmission path.
3.3.8.9 T1 SETTINGS
The three switches are used to make settings to adapt the T1 interface to the
network. The settings for T1 FORMAT and LINE CODE can be obtained from
the network operator.
Typical values for the line length can be set with the LINE LENGTH switch:
Setting Meaning
DOUBLE FRAME Frame alignment signal without CRC evaluation (see SECTION 1.3)
CRC MULTIFRAME Frame alignment signal with CRC evaluation (see SECTION 1.3)
Setting PIC/PULP cable (range/m) ICOT cable
*)
(range/m)
CEPT (standard)
−
-
L1/G.703 0 - 35 0 - 80
L2 25 - 65 65 - 145
L3 55 - 95 130 - 210
L4 85 - 125 195 - 275
L5 115 - 155 260 - 340
L6 145 - 185 325 - 405
L7 175 - 210 390 - 470
*) The characteristic impedance for ICOT cables is 140
Ω
!