ADTRAN ISU 2x64, User Manual

Page: 39 / 165

Chapter 5. Testing
61200051L1-1D ISU 2x64 Dual Port ISDN Service Unit User Manual
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Loopback Remote
This test causes the ISU 2x64 to issue a V.54 inband loopback
command to a far-end unit. External test equipment must be
used to generate/check test patterns. To use this feature, both
units must be configured for Clear Channel operation and the far-
end unit must be able to respond to V.54 loopback commands.
See Setting Protocol Options on page 55 to configure the unit for
Clear Channel operation. Press
Cancel to end the test.
Test Remote
This test causes the ISU 2x64 to issue a V.54 inband loopback com-
mand to a far-end unit and BERT test the link using a built-in pattern
generator/checker. This allows a circuit to be tested without any
extra test equipment. To use this feature, both units must be config-
ured for Clear Channel operation and the far-end unit must be able
to respond to V.54 loopback commands. See the section Setting Pro-
tocol Options to configure the unit for Clear Channel operation. The
built-in 2047 pattern generator/checker displays the number of
bytes transmitted on the top line and the number of errored bytes
received on the lower line of the front panel display. Pressing
0 will
clear the counts. Pressing the Cancel key ends the test. Pressing the
down arrow will loop down the remote unit, allowing a test to a
loopback plug. Pressing
2 will insert errors.
Loopback Disable
The following options are available in Loopback Disable.
No Rem Lpbks : The ISU 2x64 ignores all V.54 and DDS loopback
commands.
DDS Accepted : The ISU 2x64 responds to DDS latching loopback
commands. This option only takes effect if the unit is in Leased
Line mode.
V.54 Accepted : The ISU responds to V.54 loopback commands.
DDS+V54 Accept : The ISU 2x64 responds to both DDS latching
loopback commands (Leased Line mode only) and V.54 loopback
commands.