OmniAccess 780 Overview
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OmniAccess 780 Hardware Users Guide
Alcatel-Lucent
U
NIVERSAL
S
ERIAL
P
ORT
(USP) L
INE
C
ARD
(V.35/X.21/RS-232)
USP Card (V.35/X.21/RS-232) provides WAN termination for four ports over serial
sync interfaces. The line card can be installed in any of the line card slots of the
chassis. (i.e., 0, 1, 2, 3, 4 or 5).
The card allows full duplex operation on a single
copper pair and operates in either DTE of DCE mode depending on the cable
attached.
V.35, X.21 and RS-232 are well known communication protocols over
synchronous serial lines.
V.35 Interface
The V.35 interface was originally specified by CCITT as an interface for 48 Kbps
line transmissions. It has been adopted for all line speeds above 20 Kbps.
V.35 is a mixture of balanced and common earth signal interfaces. The control
lines including DTR, DSR. DCD, RTS, and CTS are single wire common earth
interfaces. The data and clock signals are balanced signals.
X.21 Interface
The physical interface between the DTE and the DCE is defined in ITU-T
recommendation as X.21. The DCE provides a full-duplex, bit-serial, synchronous
transmission path between the DTE and the local PSE. It can operate at data
rates from 600 bps.
RS-232 Interface
RS-232 is specified by Electronic Industries Association. It specifies signal
voltage, timing, function, a protocol for information exchange, and mechanical
connectors. Signal function includes signal for ground, data interchange, flow
control, control of the remote modem, modem status and control signals. For
synchronous communication, these signals provide timing information for the
transmitter and receiver, which may operate at different baud rates.
1.
V.35/X.21/RS-232 Card LEDs
2.
V.35/X.21/RS-232 Port LEDs
3.
68 pin VHDCI Connector
4.
Thumb Screw
Figure 10: USP Line Card (V.35/X.21/RS-232)
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3
1
2
