Multi-Tech Systems BL-Series Am Losing Data, Am Getting Garbage Characters on the Monitor, 128

MultiModemBL 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.

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