∙Audio Tower-to-Supervisor Headset Jack Box (if used)
∙Audio Tower-to-Operator Headset Jack Box (if used)
∙Audio Tower-to-Boom/Gooseneck Mic (if used)
∙Audio Tower-to-Boom/Gooseneck PTT and Monitor Switches (if used)
∙Audio Tower-to-Footswitches (if used)
∙Audio Tower-to-Volume Controller Box (if used)
∙Audio Tower-to-Speakers (if used)
∙PC, Video Display Monitor and Audio Tower AC Power Connections
In addition, the following interconnections are required for optional equipment, if employed:
∙Audio Tower-to-Recorder Equipment
∙Audio Tower-to-Pager
∙Audio Tower-to-External Equipment Controlled by Relay Form-A Contacts
∙Audio Tower-to-Call Director
IMPORTANT NOTE
Unless otherwise noted, all procedures in this manual should be performed in the order presented.
CEC/IMC INTERCONNECTIONS
The C3 Maestro console interfaces to the CEC/IMC via a full-duplex serial control data link and a 4-wire audio connection. In addition, each unselect speaker requires an additional 2-wire connection from the CEC/IMC. Also, if the console is interfaced to a Call Director for Call Director telephone patch operations, an additional 4-wire audio link between the C3 Maestro and the CEC/IMC is required. See Figures 1 and 8. As shown in Figure 8, all CEC/IMC interconnections are made at Concentrator Cards. These cards are located at the back of the CEC/IMC cabinet.
CEC/IMC Concentrator Card pin-out details are listed on the customer-specific system documentation print-outs. These print-outs are included with the CEC/IMC when it ships from the factory. See the CEC/IMC Digital Audio
Switch Customer-Specific System Documentation
maintenance manual, LBI-38939 for sample print-outs and complete print-out explanations.
Control Data Link
Either an RS-422 (four-wire) or an RS-232 (three- wire) serial control data link may be employed. RS-422 control data interfacing is recommended and in most all installations, it is used for co-located console interconnections. RS-232 has poorer noise performance than RS-422 and therefore, it should never be used for cable runs more than 50 feet in length.
If required for a remote console installation, full- duplex 4-wire data modems can be used between the C3 Maestro and the CEC/IMC. See the following subsection for additional remote console wiring and modem configuration details.
At the C3 Maestro, control data connections terminate at the PC's COM1 serial port. On the CEC/IMC side, the console's control data connections are made at a Data Concentrator Card. As shown in Figure 8A, punch blocks may be installed between the CEC/IMC and the console. Also shown in the figure, a Concentrator Card Cable interconnects the Data Concentrator Card to the CIM Controller Board via the CEC/IMC Backplane.
All Data General (DG) Dasher computers are factory equipped with a built-in COM1 serial port on the main board that can be wired for RS-422 or RS-232 operation. The connector is a DB-25 type. See Figure 8A.
Computers not equipped with a main board RS-422 capable COM1 port normally have a plug-in RS-422 board installed in an expansion slot. This board has a DB-25 connector at its rear plate. Approved RS-422 plug-in board
model numbers include RS422AT-P, RS422I-P and 3PXOCC1A. An RS422x-x board (part number 344A3927P38) can easily be identified by the presence of two LED indicators visible on its rear plate. If a plug-in RS-422 board is used, the PC's main board COM1 port must be disabled. This is done via a DIP switch, jumper, or a BIOS set-up program. For COM1 port enable/disable configuration details, refer to the section entitled
"SOFTWARE INSTALLATION AND SET-UP
PROCEDURE", subsection "PC CMOS SET-UP PROGRAM" later in this manual, and the PC manufacturer's documentation.
Factory-installed RS422x-x (344A3927P38) or 3PXOCC1A plug-in boards are configured correctly before the PC ships from the factory. This configuration includes disabling the PC's main board COM1 port per manufacturer's instructions.
