918 NTAK20Clock Controller daughterboard
If the command "free run" is given, the clock controller enters the free-run
mode and remains there until a new command is received. Note that the
free-run mode of operation automatically initiates after the clock controller
has been enabled.
In the temporary absence of a synchronization reference signal, or when
sudden changes occur on the incoming reference due to error bursts, the
clock controller provides a stable holdover. Free-run mode is initiated when
the clock controller has no record of the quality of the incoming reference
clock.
If the command "free run" is given, the clock controller enters the free-run
mode and remains there until a new command is received. Free-run
automatically initiates after the clock controller has been enabled.
CPU-MUX bus interface
A parallel I/O port on the clock controller provides a communication channel
between the clock controller and the CPU.
A parallel I/O port on the clock controller. provides a communication channel
between the clock controller and the CPU.
A parallel I/O port on the clock controller provides a communication channel
between the clock controller and the CPU.
Signal conditioning
Drivers and buffers are providedfor all outgoing and incoming lines.
Drivers and buffers are providedfor all outgoing and incoming lines.
Drivers and buffers are providedfor all outgoing and incoming lines.
Sanity timer
The sanity timer resets the microprocessor in the event of system hang-up.
sanity timer resets the microprocessor in the event of system hang-up.
The sanity timer resets the microprocessor in the event of system hang-up.
Microprocessor
The microprocessor does the following:
•communicates with software
•monitors two references
•provides a self-test during initialization
Nortel Communication Server 1000
Circuit Card Reference
NN43001-311 01.04 Standard
Release 5.0 23 May 2008
Copyright© 2003-2008, Nor tel Networks
.