Verilink PRISM 3021 (34-00262) Product Manual - Manual (Page 30)

4-8 Terminal Operation PRISM 3021
Element Maintenance Screen
The Element Maintenance screen (Figure 4 -8) allows per-
forming loop tests and/or BERT functions on the E1 circuit.
A BERT is performed by using on-board test facilities with
no other test equipment needed. Some of these tests may
also be activated by the front panel switch as described in
section Front Panel Testing on page 3-2. Diagram 1 of Fig-
ure 4-9 on page 4-10 shows a normally operating 3021.
C LEAR T ESTS
Pressing ENTER on this field clears all local tests and any
line loops that have been initiated.
C LEAR A LARMS
Pressing ENTER on this field causes all near-end alarms to
be cleared.
E1 L OOP
The type of E1 loop is chosen by toggling the spacebar and
is executed by pressing ENTER (Loop changes can be made
only when the test is not in the active mode). This unit sup-
ports the following types of loops which are graphically rep-
resented on page 4 -10 and page 4-11.
NET PLB: (Payload Loopback): As shown in diagram 2 of
Figure 4-9 on page 4-10, the received network signal is
looped back toward the network with signal regeneration,
framing, and CRC regeneration. Framed all-1s are passed to
the DTE ports. The NET PLB may be activated by receipt of
out of band loop code on the network receive signal or by
selection in the user interface maintenance screen.
FAR PLB: This selection activates a NET PLB on the
remote-end unit.
NET LLB: (Line Loopback): As shown in diagram 3 of
Figure 4-9 on page 4-10, the received network signal loops
back toward the network with signal regeneration only
(framing and CRC intact). During the NET LLB, data from
the DTE loops back to the DTE. The NET LLB can be acti-
vated by receipt of in-band or out-of-band loop code on the
network receive signal, by the front panel loop switch, or by
selection in the interface maintenance screen. Setting the
front-panel test switch to LOC activates this loopback.
FAR LLB: This selection activates a NET LLB on the
remote-end unit. Setting the front-panel test switch to FAR
activates this loopback.
Figure 4-8 Element Maintenance Screen
3021 DSU 1.00/1.01 P R I S M 3 0 2 1 Date: 03/15/96
No Far End Response Time: 13:52:19
------------------------------ ELEMENT MAINTENANCE ---------------------------
BERT: [E1 NET ]
(CLEAR TESTS) Pattern: [QRSS ]
(CLEAR ALARMS) Test Length: [Cont. ]
E1 Loop: [FAR PLB] Pattern Sync: NO TEST
E1 Unloop: [FAR PLB] Elapsed Time: 00:00:00
Bit Errors: 0
Port Loop: [One NEAR ] Errored Seconds: 0
Port Unloop:[One NEAR ] % EFS: 100
(START TEST)
(RESET ERRORS)
E1-NET Status: OK
E1-DTE Status: OK
Near Loops:
Far Loops:
----------------------------------- Messages ---------------------------------