Specifications

Installation and Operation Manual Chapter 1 Introduction
FCD-E1LC Ver. 1.0 Functional Description 1-7
• User interface subsystem (data channels with serial interfaces and Ethernet
port)
• Timing subsystem
• Test subsystem
• Management subsystem
• Power supply subsystem.
The characteristics of the various subsystems are explained below.
Internal Bus Functions
The FCD-E1LC system performs its various functions by controlling the flow of
data among the various user, sub and main link interfaces in accordance with the
application requirements.
The flow of data is performed through the FCD-E1LC buses, as shown in
Figure 1-4 . FCD-E1LC comprises several buses:
• TDM bus, which carries the data to the main link. The TDM bus serves as a
highway through which all the information processed by the FCD-E1LC flows.
The information is deposited and collected in discrete time intervals, called
timeslots (one timeslot supports a data rate of 64 kbps – see
Appendix C ). The
TDM bus consists of two lines:
 TSER line – carries the transmit data to the main link interface. The other
interfaces deposit data on this line, in the timeslots specified by the
management subsystem.
 RSER line – carries the data received by the main link interface. The other
interfaces read their data from the timeslots specified by the
management subsystem.
Each FCD-E1LC port deposits payload information received through its
external interface on one TDM bus line, and simultaneously collects the
information to be sent through the external interface from the other line.
Therefore, considerable flexibility is available with respect to routing, because
each port has access to all the payload information, and can be instructed by
the management subsystem to read and write the desired information in the
desired timeslots of the FCD-E1LC TDM bus.
• Clock bus, which carries the various clock signals used by the FCD-E1LC
system. The FCD-E1LC can lock its system (nodal) clock to various clock
signals applied to its ports, in accordance with the application requirements.
• Two management buses:
 Address bus – carries routing information from the management
subsystem to the other subsystems.
 Data bus – carries the internal management data.