User manual

Wide Bank 28 DS3 - Release 2.4 July 2004 7-19
Diagnostics & Troubleshooting
Testing Low-Speed Interface Operation
Testing Low-Speed Near-End with Loop Tests
 DS1 Line Loopback ... 7-20
 DS1 Equipment Loopback ... 7-20
 DS1 Metallic Loopback ... 7-21
 DS1 NIU Loopback ... 7-22
 DS1 NIU Loopback Using Two Wide Banks ... 7-23
 DS1 Send CSU Loopback Toward Drop ... 7-24
 DS1 Send NIU Loopup Code Toward Drop ... 7-25
 DS1 Send NIU Loopup Code Toward Network ... 7-26
NOTE: When the low-speed mode (lsmode) is set to either ds1ls or e1ls, the ds1
command becomes the ls command. The operation of the ls command is identical to the
ds1 command, except the references to the circuits are changed to either LS, DS1, or E1.
See Chapter 8 for lsmode description.
The command ds1 [n|range|all] setting allows you to select one or more DS1 or E1 circuits
for use with most loopback tests. The n can be a range (ds1 1-6), an individual circuit (ds1 1), a
group of individual circuits (ds1 1-4,7,12,15), or a combination of ranges and individual
circuits (ds1 1-4,5,7,13-16). One exception is the metallic loopback, which is limited to four
circuits.
A test set should be used on the low-speed side to send patterns and perform loopback tests on each
of the available low-speed circuits, as indicated in the following procedure.