Multitech MT1432BA - Manual (Page 128)

128
MultiModemBA User Guide
I Am Losing Data
• If you are using data compression and a high speed serial port, set the serial port baud rate to
four times the data rate.
• Your UART may 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.
• Make sure the flow control method you selected in software matches the method selected in the
modem. If you have a Macintosh, you may have the wrong cable for hardware flow control.
• If you are running under Windows 3.1 and have a 16550AFN UART, you may need to turn on the
16550’s data buffers and/or replace the Windows serial driver, COMM.DRV.
• Try entering the L8 (List Online Diagnostics) command in on-line mode, making a screen print of
the diagnostics listing, and checking for parameters that may be unacceptable (number of
retrains, round trip delay, etc.).
I Am Getting Garbage Characters on the Monitor
• Your computer and the remote computer may 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
communications software.
• You may be experiencing line noise. Enable error correction, if it is disabled, or hang up and call
again; you may get a better connection.
• 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.)
• Try entering the L8 (List Online Diagnostics) command in on-line mode, making a screen print of
the diagnostics listing, and checking for parameters that may be unacceptable (number of
retrains, round trip delay, etc.).
My Fax and Communications Software Won’t Run at the Same Time
Communications devices can be accessed by only one application at a time. Under DOS or Windows
3.1x, you can run either your fax software or your datacomm software, but not both at the same time,
unless you have a special communications device management application, such as Multi-Tech’s
Virtual Modem Driver. In Windows 95, you can have data and fax communication applications open
at the same time, but they cannot use the same modem at the same time.