Reference Manual

Unit Description, DXU-21
• Compact Flash Card
6.2.1 CPU System
The heart of the DXU-21 is a 32–bit embedded controller with a
PPC 405 processor core with interfaces to a wide range of peripherals.
The CPU system consists of:
• I
2
C controller
• Ethernet 10/100 Mbit/s (full-duplex) controller, MAC
• SDRAM memory
• FLASH memory
• ASIC GARP
• Compact Flash Card
6.2.2 Communication Switch System
This system block contains circuits that handle traffic between the BSC
and the TRUs.
6.2.3 Transmission Interface Controller
This part contains circuits for four transmission links and the
transmission interface controller, which controls the traffic for all four
transmission links.
The bit rate is SW controlled. Two speeds are available: E1
(2.048 Mbit/s) or T1 (1.544 Mbit/s).
6.2.4 Power Supply
The power supply delivers all the voltages necessary for the DXU-21.
The input voltage +24 V DC is supplied through the backplane
connectors.
6.2.5 Timing System
The timing system is used for generating a 13 MHz clock signal.
6.2.6 Miscellaneous Logic
This function contains the following:
• System voltage measurement
• Temperature measurement
• Power on reset
6.2.7 Compact Flash Card
The removable Compact Flash Card permits quick and easy change of
the SW and IDB in the DXU.
EN/LZT 720 0008 R1A
2001-06-26
119 (421)
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