Coastcom D/I Mux III System, User Manual

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Chapter 1. System Overview and Modes of Operation
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Common Equipment Units and Line Cards
The common equipment units and line cards are separately packaged plug-in circuit boards that are
installed into the D/I Mux III shelf. The upper front edge of each unit is fitted with a captive screw that
secures it to the D/I Mux III shelf. Inputs and outputs are terminated in gold-plated contacts on the rear
edge of the circuit board. See Figure 1-9 for an illustration of a D/I Mux III channel card unit including
descriptive front panel.
Figure 1-9. Typical D/I Mux III Channel Card
Common Equipment
The following section lists and describes the D/I Mux III system common equipment. The common
equipment functions are illustrated in simplified block diagrams.
Common Control Unit
The Common Control Unit (CCU) stores the operating parameters for control and monitoring of all common
equipment and channel cards in the D/I Mux III. The primary functions of the CCU are as follows.
•
Provide an interface for an asynchronous terminal or network management system
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Control and monitor other common equipment and channel cards
•
Manage all alarm functions
•
Control T1 clock selection
•
Control alarm cutoff (ACO) and bypass (BYP) functions
•
Provide a date and time clock (“real time” clock)
•
Provide nonvolatile storage of the shelf configuration
See Figure 1-10 for a detailed CCU motherboard circuit flow block diagram.
Status