Character Format Problems - AT&T DataPort PCX Modem User Manual

Troubleshooting
S: Set the software's DTE rate (the speed of the modem-
to-computer connection) to a lower speed. (Your software
may refer to this as the Baud Rate.) The internal DataPort
PCX modems use a 16550A-compatible UART; however,
the external DataPort PCX modems depend on the
computer's COM port UART. If you know your PC has a
slower UART such as an 8250, or you do not know what
kind of UART it has, do not exceed a DTE rate of
19,200 bps. If a successful transfer occurs at low speeds,
then you may want to upgrade your computer's COM port
UART.
S: Use a different file transfer protocol. Some protocols, such
as Ymodem-G, are very sensitive and may cancel your file
transfer. Try the Zmodem protocol.
S: The Xmodem protocol may conflict with error control (such
as V.42). Issue the AT \N0 command to turn off error control
when you are using Xmodem.
S: For Windows systems, ensure that the flow control setting
of the port under the Control Panel is the same as that
specified in your communications program.

Character Format Problems

P: You make a successful connection, but nonsensical
strings of characters appear on your screen.
S: The other modem may be configured for a different
character set. Check the number of data bits, type of parity,
and number of stop bits required by the remote system you
are trying to communicate with.
Refer to your software documentation for instructions on
changing your character set. In QuickLink II Fax, use the
Line Settings window.
S: If there is an Autobaud setting in your software, disable it.
S: Configure the modem for no error control (AT \N0).
Issue 2 July 1995
6-7