Switched-56 Network Interface; Table 3-1: Signal Flow For The Switched-56 Network Interface Board - PictureTel Concorde 4500 Servicing Manual

Switched-56 Network Interface

The switched-56 network is used in the United States only.
The four-wire switched-56 communication interface operates at
a data rate of 56 kbps on each channel over distances of up to
107 meters (350 feet).
This network interface uses two cables with RJ-45 eight pin
connectors.
See Appendix C, ÒElectronics Module Connections,Ó for
information on the Switched-56 network interface panel. See
Appendix B for information on pin assignments.
Network companies that provide CSDC switched-56 service
include:
AT&T ACCUNET™
US Sprint VPN
MCI
Regional Bell companies
The CSDC switched-56 network interface connection is a four-wire
interface that uses one RJ-48S modular jack for each of the two
channels. The interface uses pulse dialing, which is included in the
four-wire CSDC interface.
The switched-56 network interface board uses green LEDs located
along the back edge of the board to indicate when a network signal
is present. An amber LED indicates that there is no signal present.
The following table describes the signal ßow between a switched-56
network interface board and the network. The signals are listed in
the order in which they appear on the back edge of the board
Table 3-1: Signal Flow for the Switched-56 Network
Signal
DTR
DCD
RTS
Interface Board
Description
Data terminal ready
Data carrier detect
Request to send
Concorde¥4500 Network Interfaces
Direction of Flow
CSU board <---->CP
Ñ Ñ Ñ Ñ Ñ Ñ Ñ Ñ Ñ>
<Ñ Ñ Ñ Ñ Ñ Ñ Ñ Ñ Ñ
ÐÑ Ñ Ñ Ñ Ñ Ñ Ñ Ñ Ñ>
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