Loopback Operation; Generic Loopback Commands; Loopback Summary - ADC HiGain H2TU-C-231 User Manual

LTPH-UM-1109-01, Issue 1
L O
OOPBACK PERATION
HiGain HDSL2 has a family of loopback options for analyzing circuit functionality. The loopback signal is
transmitted and returned to the sending device for comparison. This allows you to verify the integrity of the
HDSL2 channels to the H2TU-C, the H2TU-C DSX-1 interface, and the DS1 channels to the customer. Loopback
options include:
• Generic Loopback (GNLB) options, including the SmartJack (SMJK) option (see
• Special Loopback (SPLB) options (see
command tables:
–
Addressable Repeater Loopback commands: A1LB, A2LB, A5LB (see
–
Addressable Repeater Loopback commands: A3LB, A4LB (see
Loopback commands can be initiated by:
• Selecting the loopback type using the MODE and SEL pushbuttons on the H2TU-C front panel or the manual
loopback (LBK) pushbutton on the H2TU-R
•
Selecting the loopback type from the Monitor Menu when connected to the craft port of the H2TU-C or
H2TU-R
•
Entering the loopback code (exceptions are COLB and RULB) into the test equipment connected to the
H2TU-C-231 or H2TU-R.
Activate loopback using
one of the following:
• MODE/SEL pushbuttons
• Maintenance Terminal
• Test Set

Generic Loopback Commands

The HiGain Generic Loopback (GNLB) commands allow you to use inband codes to loop up either NLOC
(4-in-7) or NREM (3-in-7) towards the network. In addition, these inband codes loop up CREM (6-in-7) or CLOC
(5-in-7) towards the customer. Either loopup condition can be terminated (looped down) with the 3-in-5, SMJK
loopdown code. All inband codes must be present for at least 5 seconds before the HiGain HDSL2 system
responds. TLOS is a logic loopback caused by loss of the DS1 input from the CI.
Figure 28 on page 48
the HiGain HDSL2 generic loopback commands.
H2TU-C-231 List 2
"Special Loopback Commands" on page
NLOC CREM
H2TU-C
Network
Figure 27. Loopback Summary
summarizes the available loopbacks in the system, and
January 9, 2002
Table 16 on page
45) and the following
Table 17 on page
Table 18 on page
Activate loopback using
one of the following:
• LBK pushbutton
NREM
• Maintenance Terminal
SMJK CLOC
• Test Set
TLOS
H2TU-R
Customer
Premises
Table 16
Testing
44)
49)
51)
on this page summarizes
43