Paradyne ACCULINK 317x E1 - Manual (Page 75)

ACCULINK 317x E1 DSU/CSU
4-16 December 1996 3170-A2-GB20-20
Starting a Line Loopback
The Line Loopback command (LLB) loops the
received signal on the network interface back to the
network without change.
To perform a Line loopback,
1. Press F2 to select Test from the top-level display
screen.
2. From the Test screen, press F2 to select Lpbk.
F1
Test:
Rlpbk Lpbk
Ptrns
F2 F3
3. From the Loopback screen, press F2 to select
LLB.
F1
Loopback:
Abort
LLB PLB
F2 F3
Test Started appears on Line 2. If a line 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 4-8 for valid
loopback test combinations).
Starting a Payload Loopback
The Payload Loopback command (PLB) loops the
received signal on the network interface back to the
network. The signal is looped back as close to the DTE
Drop/Insert port as possible (after it has passed through
the framing circuitry of the E1 DSU/CSU). Therefore,
framing CRCs and BPVs are corrected.
To perform a Payload loopback,
1. Press F2 to select Test from the top-level menu
screen.
2. From the Test screen, press F2 to select Lpbk.
F1
Test:
Rlpbk Lpbk
Ptrns
F2 F3
3. From the Loopback screen, press F3 to select
PLB.
F1
Loopback:
Abort
LLB PLB
F2 F3
Test Started appears on Line 2. If a Payload
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 4-8 for
valid loopback test combinations).