14-4
C
HAPTER
14: T
ESTING
THE
C
ONNECTION
If you use the S18 test timer, but in the process of testing you issue an
ATZ command, S18 resets to zero and the timer is disabled. You cannot
store a value for S18 in NVRAM; its power-on and reset default is always
zero.
Using AT&T8
This analog loopback option causes the Business Modem to send an
internal test pattern to its transmitter and loop it back to the receiver. An
internal error detector counts any errors and, when the test is ended,
sends the number of errors or 000 (no errors) to the screen.
Since you don't type anything during this test, and the Business Modem
does not send anything to the screen, this option verifies only the
Business Modem. If there are no errors but your problem continues, it
may be at the computer interface.
1
Send
AT&M0&N3S14.0=0
to the modem prepare for testing.
This command disables error control, fixes the connection rate at 2400
bps, and makes the Business Modem return to command mode when
you type
+++
.
2
Send
AT&T8
to begin the test.
The Business Modem enters analog loopback (AL) mode, and sends a
CONNECT message. The MR status light flashes. The V.Everyhing then
sends its internal test pattern to the transmitter, and loops the pattern
back to the receiver. You will not see any data on your screen.
3
Send the escape code,
+++
, and then
AT&T0
to end the test.
Alternatively, you can end the test by sending ATH or ATZ. Be careful,
because ATZ resets the modem in addition to ending the test.
In any case, the Business Modem hangs up and returns a three-digit
code, followed by OK.
4
Send
AT&M4
, unless you used a reset command (ATZ or ATZ!).
The code
Indicates
000
No errors were found
255
255 or more errors
An ERROR message indicates that you issued an invalid command.
Summary of Contents for OfficeConnect 56K Business
Page 14: ...4 ABOUT THIS GUIDE ...
Page 32: ...1 18 CHAPTER 1 CONNECTING TO YOUR ISP ...
Page 42: ...3 6 CHAPTER 3 MODES OF OPERATION ...
Page 64: ...7 4 CHAPTER 7 CONTROLLING EIA 232 SIGNALING ...
Page 72: ...8 8 CHAPTER 8 CONTROLLING DATA RATES ...
Page 80: ...9 8 CHAPTER 9 ACCESSING AND CONFIGURING THE BUSINESS MODEM REMOTELY ...
Page 96: ...11 6 CHAPTER 11 FLOW CONTROL ...
Page 108: ...12 12 CHAPTER 12 HANDSHAKING ERROR CONTROL DATA COMPRESSION AND THROUGHPUT ...
Page 112: ...13 4 CHAPTER 13 DISPLAYING QUERYING AND HELP SCREENS ...
Page 124: ...14 12 CHAPTER 14 TESTING THE CONNECTION ...
Page 132: ...15 8 CHAPTER 15 TROUBLESHOOTING ...
Page 162: ...B 14 APPENDIX B ALPHABETIC COMMAND SUMMARY ...
Page 168: ...C 6 APPENDIX C FLOW CONTROL TEMPLATE ...
Page 210: ...14 GLOSSARY ...