Chapter 4 - Troubleshooting
Multi-Tech Systems, Inc. MT9234ZPX User Guide
47
Data
Is
Being
Lost
●
If you are using data compression, set the serial port baud rate to two to six times faster than the data rate.
●
Make sure the flow control method you selected in your software matches the method selected in the
modem (see AT commands
&K
and
\Q
.)
●
Enter the
I11
command in command mode and before the modem is reset to display information about the
last connection. Then make a screen print of the connection statistics, and look for unacceptable
parameters. To display information about the present configuration, you must use the escape sequence,
+++, to ensure command mode while still on line. To return to on line mode, set ATO.
There
Are
Garbage
Characters
on
the
Monitor
●
Your computer and the remote computer might be set to different word lengths, stop bits, or parities. If you
have connected at 8-N-1, try changing to 7-E-1, or vice-versa, using your communication software.
●
You might be experiencing line noise. Enable error correction, if it is disabled, or hang up and call again;
you might get a better connection the second time.
●
At speeds above 2400 bps, the remote modem might not use the same transmission or error correction
standards as your modem. Try connecting at a slower speed or disabling error correction. (With no error
correction, however, line noise can cause garbage characters.).
●
Enter the
I11
command in command mode and before the modem is reset to display information about the
last connection. Then make a screen print of the connection statistics, and look for unacceptable
parameters. To display information about the present configuration, you must use the escape sequence,
+++, to ensure command mode while still on line. To return to on line mode, set ATO.
The
Modem
Doesn’t
Work
with
Caller
ID
●
Caller ID information is transmitted between the first and second rings, so if autoanswer is turned off (
S0=0
)
or if the modem is set to answer after only one ring (
S0=1
), the modem will not receive Caller ID
information. Check your initialization string, and if necessary change it to set the modem to answer after the
second ring (
S0=2
).
●
Make sure that you have Caller ID service from your telephone company.
Fax
and
Data
Software
Can’t
Run
at
the
Same
Time
●
Communication devices can be accessed by only one application at a time. In Windows 2000 and higher,
you can have data and fax communication applications open at the same time, but they cannot use the
same modem at the same time.
The
Voice
Functions
Don’t
Work
●
There are several tests that you can perform to verify the voice circuits of the MultiModem. First, make sure
all connecting cables—telephone, microphone, and speaker—are undamaged and firmly connected to the
correct jacks. Then retry whatever action was not working. If the problem persists, try the voice mail test; if
that doesn’t work, and if you have a microphone and speaker connected to the MultiModem, try the
loopback and speakerphone tests, which do not require special software.
Voice
Test
●
Test the MultiModem’s voice function set up the MultiModem for voice mail. Have an acquaintance call and
leave a message, and then play it back.
If your modem does not play sound files in voice mode, go to Windows Control Panel and double-click the
Multimodem icon. Under the
Audio
tab, select
Modem Wave Driver
as your preferred device for both
playback and recording, then try again.
