PairGain HiGain HLU-319 Manual page 37

150-319-142-01
•
If a loopback is in effect, the 30 second time-out does not occur. The
active loopback session continues until the loopback times out in
accordance with the LBTO setting.
•
Only the SMJK loopback can exist with other networks at any given
time.
•
When a loopback is active, pressing both buttons for three seconds
terminates the loopback, ends the manual loopback session, and returns
the front panel display to the normal mode.
To initiate a manual loopback session:
1 Simultaneously press the MODE and SEL buttons for at least three
seconds. The following message appears on the front panel display:
MAN LPBK
followed by the message:
NLO
2 Do one of the following:
•
To execute an NLOC loopback, press the SEL button. The message
changes from NLO to NLOC.
•
To execute an NREM loopback:
–
–
•
To execute a CREM loopback, press the MODE button again.
•
To execute a CLOC loopback, press the MODE button a third time.
Note that these same loopbacks can be initiated from the Craft (RS-232) port
by choosing the Option D, Loopback Mode, on the Main Menu.
All loopbacks, except the SMJK loopback, are initiated by in-band
commands in the T1 payload or by a command from the HLU-319 List 4B
(front panel buttons or maintenance screen selections). Initiate loopbacks
using HG for the HLU-319 List 4B or PL for T1 payload on the Loopback
Menu and Span Status screen.
HLU-319 List 4B
December 22, 1997
Press the MODE button. The message changes from NLO to
NRE.
Press the SEL button to execute the NREM loopback.
PairGain Engineering - Plant Series
Revision 01
31