14-2
C
HAPTER
14: T
ESTING
THE
C
ONNECTION
Testing the Business
Modem using
AT&Tn
To perform digital loopback and remote digital loopback testing use the
AT&T
n
command. You can type in your own data during testing or use
the modem's internal test pattern and error detector. See the following
sections for more detailed information about each AT&T
n
command.
Example:
Sending
AT&T5
will deny any requests from remote devices for
a remote digital loopback test of your Business Modem.
Disable error control (using the &M0 command,
see Appendix B,
Alphabetic Command Summary
) before testing. If the modem is
detecting errors and retransmitting the affected data, your results will be
invalid.
For your modem to
Command
End testing
AT&T0
Enter analog loopback (AL) mode and send a CONNECT
message. Data is shown on your screen.
AT&T1
Enter analog loopback mode and send a CONNECT
message. The Business Modem sends a internal test
pattern to the transmitter and loops the pattern back to
the receiver. No data is seen on your screen.
AT&T2
Start local digital loopback testing
AT&T3
Grant a remote digital loopback test of your Business
Modem
AT&T4
Deny a remote digital loopback test of your Business
Modem
AT&T5
Start local digital loopback testing
AT&T6
Start remote digital loopback with self-test and error
detection
AT&T7
Содержание U.S. Robotics 56K Voice
Страница 1: ...http www 3com com 3Com OfficeConnect 56K Business Modem Command Reference Published January 1999...
Страница 14: ...4 ABOUT THIS GUIDE...
Страница 32: ...1 18 CHAPTER 1 CONNECTING TO YOUR ISP...
Страница 42: ...3 6 CHAPTER 3 MODES OF OPERATION...
Страница 64: ...7 4 CHAPTER 7 CONTROLLING EIA 232 SIGNALING...
Страница 72: ...8 8 CHAPTER 8 CONTROLLING DATA RATES...
Страница 80: ...9 8 CHAPTER 9 ACCESSING AND CONFIGURING THE BUSINESS MODEM REMOTELY...
Страница 96: ...11 6 CHAPTER 11 FLOW CONTROL...
Страница 108: ...12 12 CHAPTER 12 HANDSHAKING ERROR CONTROL DATA COMPRESSION AND THROUGHPUT...
Страница 112: ...13 4 CHAPTER 13 DISPLAYING QUERYING AND HELP SCREENS...
Страница 124: ...14 12 CHAPTER 14 TESTING THE CONNECTION...
Страница 132: ...15 8 CHAPTER 15 TROUBLESHOOTING...
Страница 162: ...B 14 APPENDIX B ALPHABETIC COMMAND SUMMARY...
Страница 168: ...C 6 APPENDIX C FLOW CONTROL TEMPLATE...
Страница 210: ...14 GLOSSARY...