ADTRAN TSU 120e user manual Test Patterns All Zeros, All Ones, Qrss Pattern

	Chapter 7. Test Menu
FT1 LPBK	Initiates the transmission of a FT1
	loopback using the inband code
	described in T1.403.
NO LOOPBACK	Deactivates the loopback

Remote Loopback can only be used with Fractional T1 if the ANSI

FT1 LLB is selected.

After a Remote Loopback option is selected, the TSU 120 veri- fies that the far end is actually in a loopback by checking for the receipt of a code looped back from the far end. Once the Remote Loopback type is selected, the LCD displays the loop- back progress by displaying LOOPING until loopback is verified.

Test Patterns

All Zeros

Sends an all zeros pattern to the network.

All Ones

Sends an all ones pattern to the network.

QRSS Pattern

The QRSS pattern is commonly used to simulate real data in T1 interfaces. This pattern can be assigned to appear in all DS0s or only in TST DS0s. When QRSS is set in all DS0s and one of the network loopbacks previously described is activated at the far end, a total end-to-end integrity check can be run without the need for any external test equipment. When QRSS is assigned to TST DS0s, an integrity check of the link can be run along with normal data flow. The TST DS0s are user-assigned as part of the DS0 Map. This sets the pattern for the test and initiates the transmission of the pattern. The test is terminated by select- ing NONE. The following patterns are available:

61202129L1-1 TSU 120 User Manual 7-5