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CSU/DSU MS DBU
NOTE
For IDLE WHEN OFF option: In SW56 mode, TR off causes the DSU to go
On Hook (Idle). The unit does not dial out if TR is off. In dedicated mode,
the DSU goes into DTE command mode when TR goes off. When TR
goes on, if the DSU does not receive a command in the number of
seconds set in S40, the DSU goes into data mode.
7.1 DTE Rate
If a DTE rate higher than the current loop rate is selected, the DTE rate
automatically set to match the slower loop rate; the CSU/DSU MS DBU briefly
displays DTE RATE SAME AS THE NETWORK before returning to the status
screen. The factory-default setting is SAME AS LOOP.
If the CSU/DSU MS DBU is set for a loop rate of 64 kbps, then scrambler
on/off options are available. The factory-default setting is Scrambler Off.
CAUTION
For 64-kbps clear-channel operation, the DTE data sequences might
mimic network loop-maintenance functions and erroneously cause
other network elements to activate loopbacks. To prevents this, the
Scrambler On option should be selected for both the local and remote
CSU/DSU MS DBU.
7.2 Connector Type
The Connector Type option is used to specify which of the primary channel
connectors is used to connect to the DTE. The factory-default setting is V.35.
There are no AT commands available to set the connector type.
7.3 Data Format
The Data Format option is used to select either the synchronous or asynchronous
mode of operation for the DTE interface. The factory-default setting is
Synchronous. If asynchronous is chosen, the length of the data bytes must be
selected.
Table 7-1 shows the AT commands that can be used to set the Data Format to
asynchronous or synchronous.