Paradyne FrameSaver NP 64+, Руководство пользователя

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5 Diagnostics
980-001-0221C FrameSaver NP 64+ User’s Manual - Installation Guide 5-3
March 2001
Testing
FrameSaver NP 64+ provides management access diagnostic test support.
Diagnostic Test
Support
FrameSaver NP 64+ supports diagnostic loopback testing and can source a BER Test
directed toward the DDS circuit or toward the DTE.
A block diagram of the test paths within the FrameSaver NP 64+ is shown in
Figure 5-2.
Figure 5-2 Diagnostic Test Paths
The arrows indicate the direction of the loopbacks and direction of the sourced test.
Loops and sources are as follows:
a. CSU loop in response to reversal of line polarity.
b. Latching and non-latching DSU loop in response to network control code. Also,
the equivalent of a latching DSU loop by operator command.
c. DTE loop at the Data Port (high speed interface) by operator command.
d. Unframed 511 BER Test directed toward the DDS circuit or DTE by operator
commands issued through management session. BER results are updated every
five seconds and displayed on the DSU Test screen.
e. Framed Test Packets directed toward the DDS circuit by operator commands
issued through management session. Results are updated every five seconds and
displayed on the DST Test screen.
NOTE: A “hard” loopback applied at the unit’s DDS connector can be used to quickly
isolate a DDS Facility failure from a FrameSaver NP problem. With this loopback in
place, a working unit should display a Receive Level between -10 to 0 dB on the Sys-
tem View and DSU Statistics Summary screens. Also a BERT to Network test will
pass.
The DSU Test screen is accessed form the System View screen, selecting [DT} by
typing “DT” followed by ENTER.
(a)
D S U
F ram e
M anager
511 B E R T
H S
Interface
T o D D S
T o D T E
(b)
(d) (d)
(e)
(c)