ADC H2TU-C-231 manual 56

Testing LTPH-UM-1109-01, Issue 1

4Have 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.)

5Repeat Step 2. If the test passes, the problem is in the downstream direction. If it fails, the problem is in the upstream direction.

DSX-1

Loopbacks Toward Network

TLOS*

H2TU-CHDSL2 SPANLOGIC All ones H2TU-R

SMJK*

H2TU-CHDSL2 SPAN11000 2-in-5 All ones H2TU-R

				FF02 ￿
				C742 ‡	NREM*
	H2TU-C		HDSL2 SPAN	1110000	3-in-7
					H2TU-R
		FF1E ￿
	NLOC	D3D3 ‡
		1111000	HDSL2 SPAN		H2TU-R
	4-in-7
	H2TU-C
		3F1E ￿	Loopbacks Toward Customer
	CREM	D3D3 ‡
All ones	6-in-7	1111110	HDSL2 SPAN		H2TU-R
	H2TU-C
				3F02 ￿
				C742 ‡	CLOC
All ones	H2TU-C		HDSL2 SPAN	1111100	5-in-7
					H2TU-R
	H2TU-C				H2TU-R
	COLB				RULB

*Set the NLBP option to AIS to send AIS (indicated by an all ones pattern) for any network loopback.

￿A3LB and A4LB loopback codes.

‡A1LB, A2LB, and A5LB loopback codes.

GNLB loopback codes.

CI-Customer Interface

Figure 28. Loopback Modes

48 January 9, 2002 H2TU-C-231 List 2