Multi-Tech Systems MT5600BA-V92 Manuel D’Utilisation
Chapter 7 – Troubleshooting
Multi-Tech Systems, Inc. MT5600BA-V92 User Guide
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File Transfer Is Slower Than It Should Be
•
You might have an older UART. For best throughput, install a 16550AFN UART or a Multi-Tech
ISI serial port card.
ISI serial port card.
•
If you are using a slow transfer protocol, such as Xmodem, try Zmodem or Ymodem/G instead.
•
Is your line noisy? If there is static on your line, the modem has to resend many blocks of data to
insure accuracy. You must have a clean line for maximum speed.
insure accuracy. You must have a clean line for maximum speed.
•
Are you downloading a compressed file with MNP 5 hardware compression enabled? Since
hardware data compression cannot compress a file already compressed by an archiving program,
the transfer can be marginally slower with data compression enabled than with it disabled.
hardware data compression cannot compress a file already compressed by an archiving program,
the transfer can be marginally slower with data compression enabled than with it disabled.
•
Try entering the &V1 command to display information about the last connection, making a LCD
print of the connection statistics, and checking for parameters that might be unacceptable.
print of the connection statistics, and checking for parameters that might be unacceptable.
Data Is Being Lost
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If you are using data compression and a high speed serial port, set the serial port baud rate to
four times the data rate.
four times the data rate.
•
Your UART might not be reliable at serial port speeds over 9600 bps or 19,200 bps. Turn off data
compression, reset your serial port speed to a lower rate, or replace your serial port with a faster
one.
compression, reset your serial port speed to a lower rate, or replace your serial port with a faster
one.
•
Make sure the flow control method you selected in software matches the method selected in the
modem. If you are using the modem with a Macintosh, you might have the wrong cable for
hardware flow control.
modem. If you are using the modem with a Macintosh, you might have the wrong cable for
hardware flow control.
•
Try entering the &V1 command to display information about the last connection, making a LCD
print of the connection statistics, and checking for parameters that might be unacceptable.
print of the connection statistics, and checking for parameters that might be unacceptable.
There Are Garbage Characters on the Monitor
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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.
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.
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.)
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.)
•
Try entering the &V1 command to display information about the last connection, making a LCD
print of the connection statistics, and checking for parameters that might be unacceptable.
print of the connection statistics, and checking for parameters that might be unacceptable.
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).
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.