Lucent Technologies DDM-2000 OC-3, Руководство пользователя и обслуживания

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Circuit Pack Descriptions
7-6 Issue 3 June 2001
Transmission/Timing Circuit Pack Interfaces 7
The main processor can read and write parameters on the transmission circuit
packs through a custom serial interface called the intra-shelf control bus. These
circuit packs have a built-in serial link receiver which provides an address map
into the device. Through this interface, the processor accesses the custom
devices and circuit pack parameters, as well as a small EEPROM which stores
each circuit pack's inventory information (
Common Language
*
code, date of
manufacture, etc.). Through this link, the main processor can also light the
faceplate LEDs on the circuit packs.
Redundancy has been built into this bus to allow a pack to be switched out of
service in the event of a failure within a circuit pack.
Operation Interfaces 7
The SYSCTL supports all of the operations interfaces described in Section 6,
"Operations Interfaces."
OC-3 Transport Overhead Channel 7
The OHCTL terminates an overhead channel from each main and function unit
slot in the shelf, passing information to the SYSCTL over the intra-shelf processor
bus.
Power Monitoring and Fan Control 7
The SYSCTL monitors the two
−
48 volt feeders and generates an alarm if one
fails. It also monitors AC power in a RT application via a PMN alarm input closure
and can control the external fan based on an on-board temperature sensor. The
system also monitors the fan control relay for contact failure.
If the voltage to the shelf drops below the safe operating voltage, the system will
suspend normal operations and wait for safe operating voltage to return. This is
referred to as "brownout protection." Assuming a sufficient voltage level, an "L"
will be displayed on the SYSCTL. The BBG8 operates in integrated grounding
(-48VRTN connected to frame ground) architecture systems. The BBG8B
operates in either integrated or isolated grounding (-48VRTN not connected to
frame ground) architecture systems.
* Common Language is a registered trademark, and CLEI, CLLI, CLCI, and CLFI are
trademarks of Bell Communications Research, Inc.