Paradyne 336x E1 manual Starting a DTE Loopback, Starting a Repeater Loopback, Llb Plb Dlb

ACCULINK 336x E1 NTU

Starting a DTE Loopback

The DTE Loopback command (DLB) loops the received signal on the G.703 DTE port back to the DTE without change. All ones are inserted into the DS0 channels allocated to the G.703 DTE port.

A DTE loopback can be activated and deactivated based on the state of an external contact on the G.703 DTE port. If this option is enabled with the DTE Interface configuration option Extrn DLB, closing the contact activates a DLB. The DLB remains active until the contact is opened. Refer to the G.703 DTE Interface section in Appendix D, Pin Assignments, for more information.

		NTU	AIS
DTE
	DLB		HDSL
(G.703)

DTE LOOPBACK (DLB)

495-14760

To perform a DTE loopback,

1.From the top-level menu screen, select Test.

2.From the Test screen, select Lpbk.

Test:
Rlpbk	Lpbk	Ptrns
F1	F2	F3

3.From the Loopback screen, press the key until the DLB selection appears on the screen.

Loopback:

Abort LLB PLB

F1 F2 F3

4. Select DLB.

Loopback:

LLB PLB DLB

F1 F2 F3

Test Started appears on Line 2. If a DTE loopback is already in progress, the Already Active message appears. If an invalid combination of loopbacks is in progress, the error message Invld Test Combo appears (see Table 4-9for valid loopback test combinations).

Starting a Repeater Loopback

The Repeater Loopback command (RLB) loops the signal being sent to the network back to the G.703 DTE and data ports. The signal is looped back as close to the network interface as possible (after it has passed through the framing circuitry of the E1 NTU). Therefore, framing CRCs and BPVs are corrected. All ones are transmitted to the network interface.

	NTU	AIS
DTE	RLB	HDSL
(G.703)

REPEATER LOOPBACK (RLB)

495-14761

To perform a Repeater loopback,

1.From the top-level menu screen, select Test.

2.From the Test screen, select Lpbk.

Test:

Rlpbk Lpbk Ptrns

F1 F2 F3

4-18 December 1996 3360-A2-GB20-20