Reference Manual

Unit Description, DXU-21
IOM-Bus
This interface consists of three individual I
2
C ports. It is accessed
through the lower backplane connector and is used to communicate with
the CDU, CXU and cabinet ID.
An I
2
C bus is reserved for reading a memory device which identifies
the source for the system.
The interface is accessed through the lower backplane connector.
Y-Links
This interface is used for communication with the dTRUs and sTRUs.
The Y-interface consists of 12 separate Y-links.
The Y-links are accessed through connectors located on the front of the
DXU.
EPC-Bus (Optical Cable)
This interface is used for communication with the power supply
equipment in the RBS, such as PSUs and BFU.
The optical communication interface is accessible through connectors
located on the front of the DXU. The connectors are marked "EPC".
The EPC-bus is not used in RBS 2101/2102/2202.
External Sync. 1 (GPS/LMU)
This interface is used for interfacing an external sync./frequency source,
such as GPS. It is accessed through a connector of type 8-pin RJ-45,
located on the front of the DXU. The connector is marked "GPS".
GPS/LMU
This interface is identical to the serial line used in the interface
"External sync. 1".
It is possible to use this interface from the backplane together with the
interface "External sync. 0", as an alternative to the GPS interface.
This interface is accessed through the lower backplane connector.
External O&M (EOM)
The EOM bus is designed as a standard Ethernet port and is intended
for a site-LAN to communicate with other units on the site. Both half-
duplex and full-duplex operation at 10 Mbps and 100 Mbps operation
are supported.
The EOM bus is accessed through a connector located on the front of
the DXU marked "EOM". The connector is of type 8–pin RJ-45.
OMT
The OMT interface is used for maintenance and supervision purposes.
This interface is accessed on the front of the DXU through a 9–pin
female D-sub connector marked "OMT".
152 (485)
EN/LZT 720 0008 P2A
2001-11-28
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Preliminary