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90
CSU/DSU MS DBU
Open Loop
The physical connection to the backup line
has been broken (4-wire SW56 only).
DBU Line in RDL
Remote end initiated a test.
Test From Telco
The network provider has activated the
CSU loopback (4-wire SW56 only).
DBU Test Pattern
The CSU/DSU MS DBU is currently
performing a test with a pattern.
Waiting for Call
The originating CSU/DSU MS DBU is waiting
on a call from the remote end.
Inactive
A DBU card is installed, but the CSU/DSU MS
DBU is set to SW56 mode.
Getting TEI
The ISU card is getting its first terminal
endpoint identifier from the network.
Register SPID
The ISU card is registering its first SPID
with the network.
DSU O
PERATION AND
N
ETWORK
S
TATUS
Current CSU/DSU MS DBU Status
This display line (see Figure 14-1) indicates current CSU/DSU MS DBU status.
Possible messages are:
Data Mode
In data mode, the Data Set Ready (SR) and
Request To Send (RTS) circuits are on, and
the CSU/DSU MS DBU is ready to send data.
Unit in Test
The CSU/DSU MS DBU is currently in test
mode; use the Arrows to scroll through the
menus to display the type of test being
performed.