2 - Installation
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Slow File Transfer• You may have an older UART. For best throughput, install a 16550AFN
UART or a Multi-Tech ISI serial port card.
• If you are running under Windows 3.1 and have a 16550AFN UART,
you must replace the Windows serial driver, COMM.DRV, to take full
advantage of the UART’s speed.
• If you are using a slow transfer protocol, such as Xmodem or Kermit,
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.
• 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.
• Try entering the
&V
(View Parameters) command, making a screen
print of the diagnostics listing, and checking for parameters that may
be unacceptable.
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 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
&V
(View Parameters) command, making a screen
print of the diagnostics listing, and checking for parameters that may
be unacceptable.