LTPH-UM-1049-02, Issue 2 Testing
H2TU-C-319 List 4E January 9, 2002 57
SmartJack Loopback Commands
The HiGain HDSL2 SmartJack (SMJK) Loopback (LPBK) commands allow you to use in-band, out-of-band, and
universal codes to initiate and terminate loopback testing of the HiGain HDSL2 circuit. (See “SmartJack Test
Procedure” on page 64 for additional information.)
MANUAL LOOPBACK SESSION
A manual loopback session allows you to select any one of the HiGain HDSL2 loopbacks listed in Table 22 on
page 56.
Setting the Loopback Time-Out Option
Before initiating a loopback session, verify that the Loopback/MTA Time-out parameter is set to the desired
setting.
1 Use the MODE and LBK pushbuttons as described in “Setting Options through MODE and LBK” on page 10.
The Loopback Time-out parameter is also user-selectable from the System Settings screen when using a
maintenance terminal.
2 Select the desired setting:
• NONE (time-out disabled)
• 20 minutes
• 60 minutes
• 120 minutes (default setting)
Activating Manual Loopback Mode
To initiate a manual loopback session:
1 Press both the MODE and LBK pushbuttons on the front panel for at least 3 seconds. The following message
appears on the front-panel display:
MAN LPBK NLO?
With the exception of SmartJack, any of the HiGain HDSL2 loopbacks can be executed using the
MODE and LBK pushbuttons.
When executing a manual loopback session using the MODE and LBK pushbuttons:
• The next loopback option can be displayed by pressing the MODE pushbutton, however, the
previously activated loopback remains active until the LBK pushbutton is pressed, which
activates the new loopback.
• If neither pushbutton is pressed for a period of 30 seconds and no loopback is in effect, the
manual loopback session terminates and the display returns to normal mode.
• If any loopback is in effect, the 30-second time-out is inhibited. The active loopback and the
manual loopback session continue until the loopback times out in accordance with the LBTO
setting.
• Only the SMJK loopback can exist with other network loopbacks at any given time.
• If there is an active loopback, pressing the MODE and LBK pushbuttons for 3 or more
seconds terminates any active loopback, ends the manual loopback session and returns the
display to normal mode.
