General DataComm DeskTop T1, Инструкция по установке и эксплуатации

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4-16 Diagnostics
GDC 048R154-000
Network Remote Test with QRSS Self Test
The data path for the Network Remote Test with QRSS Self Test is
illustrated in Figure 4-13. You can command the loopback by means
of either the terminal interface screen or the front panel switches.
When you initiate a Network Remote Test the DSU transmits a loop-
up code to the remote unit for approximately five seconds. The remote
unit responds by engaging either a Line or a Payload loopback
(determined by its optioning).
When the loop is established the DSU generates a QRSS test pattern
and transmits it to the remote DSU which loops it back to be checked
for errors at the local DSU. The DSUs are electronically disconnected
from their DTEs during the test.
Network Remote Test with a Line loopback tests the line and the
network interface at the remote DSU. Network Remote Test with a
Payload loopback extends the test to include network interface
circuitry at the remote DSU.
To initiate the test from the terminal interface Diagnostics Selection
screen, select
[8] Start Network Remote Test with
QRSS Self Test
.
Figure 4-14 shows the switches and indicators that are involved when
you command a Network Remote Test with QRSS Self Test from the
front panel.
Figure 4-13
Data Path for Network Remote Test with Self Test
Figure 4-13
Data Path for Network Remote Test with Self Test
Network
TPG – Test Pattern Generator
TPC – Test Pattern Checker
DeskTop T1 DSU
DTE
Interface
Network
Interface
TPG
TPC
DTE
Interface
Network
Interface
Line Loopback or Payload Loopback
as selected by remote DSU configuration
DeskTop T1 DSU