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Chapter 5. Testing
61202.029L2-1
ISU 128 User Manual
21
Loopback Remote
Loopback Remote
allows the ISU 128 to issue a V.54 in-band loopback com-
mand to a far-end unit while still accepting data from the DTE connector. This
provides bit error rate testing of an entire link using an external BERT test set.
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
the chapter Protocol Options to configure the unit for Clear Channel operation.
Press the
Cancel
key to end the test.
Loopback Remote 1B and 2B are only used with the DTE set to asynchronous.
Test Remote
Test Remote
allows the ISU 128 to issue a V.54 in-band loopback command to
a far-end unit and BERT the link using a built-in 2047 pattern generator/
checker. This allows for testing a circuit without any extra test equipment. 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
the chapter Protocol 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. Press
0
to clear the counts. By pressing
the down arrow, you can loop down the far end unit and run a head to head
2047 pattern test. Press
Cancel
to end the test.
Loopback Disable
The following options are available when disabling loopbacks:
No Remote Loopbacks
The ISU 128 ignores all V.54 and DDS loopback commands.
DDS Accepted
The ISU 128 responds to DSU Latching Loopback commands. This option
only takes effect if the unit is in leased line mode.
V.54 Accepted
The ISU 128 responds to V.54 loopback commands.
Содержание ISU 128
Страница 11: ...Table of Contents vi ISU 128 User Manual 61202 029L2 1 ...
Страница 15: ...List of Tables xii ISU 128 User Manual 61202 029L2 1 ...
Страница 23: ...Chapter 1 Understanding ISDN and the ISU 128 8 ISU 128 User Manual 61202 029L2 1 ...
Страница 29: ...Chapter 3 Installation 14 ISU 128 User Manual 61202 029L2 1 ...
Страница 43: ...Chapter 6 Configuration 28 ISU 128 User Manual ...
Страница 61: ...Chapter 6 Configuration 46 ISU 128 User Manual 61202 029L2 1 ...
Страница 73: ...Chapter 7 Protocol Options 58 ISU 128 User Manual 61202 029L2 1 ...
Страница 85: ...Chapter 9 Dial Options 70 ISU 128 User Manual 61202 029L2 1 ...
Страница 91: ...Chapter 10 Remote Configuration 76 ISU 128 User Manual 61202 029L2 1 ...
Страница 101: ...Chapter 12 Specifications 86 ISU 128 User Manual 61202 029L2 1 ...
Страница 107: ...Appendix A AT Commands 92 ISU 128 User Manual 61202 029L2 1 ...
Страница 111: ...Appendix B Current Status Messages 96 ISU 128 User Manual 61202 029L2 1 ...
Страница 121: ...Appendix C Status Buffer Messages 106 ISU 128 User Manual 61202 029L2 1 ...
Страница 135: ...Appendix E Connector Pinouts 120 ISU 128 User Manual 61202 029L2 1 ...
Страница 145: ...Glossary 130 ISU 128 User Manual 61202 029L2 1 ...