PictureTel Concorde 4500 Servicing Manual page 8

Chapter 2
Understanding the Electronics Module
Backplane..........................................................................................................................................2-1
Communications Board ..................................................................................................................2-9
Control Ports A and B ...........................................................................................................2-9
Video Board....................................................................................................................................2-11
Graphics Daughter Board ...................................................................................................2-12
Audio Board ...................................................................................................................................2-14
Telephone Interface Daughter Board ................................................................................2-16
Data Interface Board .....................................................................................................................2-18
Modem Control Signals ................................................................................................................2-21
Chapter 3
Network Interfaces
Concorde¥4500 Network Interfaces .............................................................................................3-2
X.21 Network Interface .........................................................................................................3-4
Switched-56 Network Interface ...........................................................................................3-5
V.35 Network Interface .........................................................................................................3-6
RS-449 Network Interface .....................................................................................................3-7
V.25 bis Network Interface ...................................................................................................3-8
Call Setup Using Nondialed and Dialed Devices.......................................................................3-9
Call Setup Using the RS-366A Dialing Procedure.............................................................3-9
V.35, RS-449, and Switched-56 Call Setup with Auto Answering .........................................3-12
Dialed Call Setup with Auto Answering..........................................................................3-12
Nondialed Call Setup with Auto Answering ..................................................................3-13
Call Setup with Manual Answering ...........................................................................................3-13
V.35, RS-449, and Switched-56 Call Disconnect........................................................................3-13
X.21 Call Setup and Disconnect...................................................................................................3-14
Placing a Dialed Call with X.21 Data Circuit-Terminating Equipment (DCE) ...........3-14
Receiving a Dialed Call from an X.21 DCE ......................................................................3-17
Placing a Nondialed Call with an X.21 DCE....................................................................3-19
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