Loopback modes – ADC H2TU-C-231 User Manual
Page 56
Testing
LTPH-UM-1109-01, Issue 1
48
January 9, 2002
H2TU-C-231 List 2
4
Have the CO tester send the NLOC (4-in-7) inband loopup for 5 seconds. You should be able to observe the
NLOC message on the front-panel display. (The Status LED on the front panel should be yellow, and the
loopback mode should also be identified on the Monitor screen.)
5
Repeat Step 2. If the test passes, the problem is in the downstream direction. If it fails, the problem is in the
upstream direction.
Figure 28.
Loopback Modes
All ones
All ones
All ones
HDSL2 SPAN
C742
‡
All ones
HDSL2 SPAN
D3D3
‡
HLU
HLU
HLU
CREM
HRU-412
5 IN 7
CLOC
HRU-412
HDSL2 SPAN
HLU
HLU
HLU
HRU-412
HRU-412
5 IN 7
CLOC
HRU-412
HRU-412
5 IN 7
CLOC
HRU-412
HRU-412
5 IN 7
CLOC
HRU-412
HRU-412
CLOC
All ones
HLU
HLU
HLU
HLU
HLU
HLU
HLU
HLU
HLU
HLU
HLU
HLU
HLU
HLU
HLU
D3D3
‡
NLOC
HRU-412
HDSL2 SPAN
HLU
HLU
HLU
HRU-412
HRU-412
3 in 7
NREM
HRU-412
HRU-412
HRU-412
HRU-412
HDSL2 SPAN
HDSL2 SPAN
HLU
HLU
HLU
HLU
HLU
HLU
HRU-412
HRU-412
HRU-412
HRU-412
HRU-412
HRU-412
C742
‡
11000
2-in-5
H2TU-C
H2TU-C
NREM*
SMJK*
TLOS*
LOGIC
Loopbacks Toward Customer
CI-Customer Interface
DSX-1
Loopbacks Toward Network
* Set the NLBP option to AIS to send AIS (indicated by an all ones pattern) for any network loopback.
H2TU-R
H2TU-R
H2TU-R
H2TU-R
H2TU-R
H2TU-R
All ones
H2TU-C
H2TU-C
H2TU-C
H2TU-C
FF02
1110000
3-in-7
FF1E
1111000
3F1E
6-in-7
1111110
3F02
1111100
5-in-7
=
=
=
=
=
A3LB and A4LB loopback codes.
‡ A1LB, A2LB, and A5LB loopback codes.
4-in-7
GNLB loopback codes.
HLU
HLU
HLU
H2TU-C
H2TU-R
COLB
RULB