Default Mode; Loopback Mode; Table 10. Loopback Options Display (Lpbk) - ADTRAN HDSL DDM+ HTU-C Installation And Maintenance Practice

Default Mode

The DFLT mode can be used to enable all of the factory default HDSL circuit configuration
parameters. Once in this mode, the user is prompted to select the factory defaults or not by
entering or respectively. The
YES NO
the pushbutton is pressed while the FCD reads
SELECT
factory defaults and display a
FCD reads , then the unit will retain the current settings.
NO

Loopback Mode

In the Loopback mode the user can select and execute one of the HDSL circuit loopbacks.
Only one loopback may be active at a time. From the top level of the FCD use
. Pressing
SELECT
LPBK
then be used to scroll through the different HDSL system units on the circuit which may
include , ,
HTUC HRE1 HRE2
HTU-C. The FCD will toggle between the unit name and the current loopback state of that
unit. The choices are
customer).
To change the loopback state of a particular unit, first press
HDSL system unit is being displayed. The unit's current loopback state will be displayed. The
pushbutton can then be used to scroll through the available choices. Once the desired
MODE
choice is on the FCD the
pushbutton can now be held down for three seconds to return to the top level of the FCD.
Available loopbacks are summarized in
Mode Select
LPBK HTUC
HTUR
HRE#1
HRE#2
61247003L6-5A
MODE
message. If the
DONE
will force the FCD into the loopback branch. The
and . HRE1 is the HDSL Range Extender closest to the DDM+
HTUR
, (loopback towards the network), and
NONE NET
pushbutton is pressed to activate the choice. The
SELECT
Table

Table 10. Loopback Options Display (LPBK)

Loopback State
NET
CST
NONE
BLB
NET
CST
NONE
NET
CST
NONE
NET
CST
NONE
pushbutton is used to toggle between
, then the unit will enable the
YES
pushbutton is pressed while the
SELECT
SELECT
10.
Loopback Description
Network loopback at HTU-C
Customer loopback at HTU-C
No active loopback
Bidirectional loopback at HTU-R
Network loopback at HTU-R
Customer loopback at HTU-R
No active loopback
Network loopback at HRE#1
Customer loopback at HRE#1
No active loopback
Network loopback at HRE#2
Customer loopback at HRE#2
No active loopback
Front Panel Operation
and
YES
to scroll to
MODE
pushbutton can
MODE
(loopback towards the
CST
when the appropriate
MODE
. If
NO
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