Multitech CC1600 Series, Owner'S Manual

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MT2834BLR Owner’s Manual
3.9 Configuring Software for Your Computer
You must configure your communications software to match your computer’s configuration. If the
modem is connected to the COM2 serial port, you must tell the software you are using COM2.
Another important parameter is the serial port baud rate. This is the speed at which your modem
communicates with your computer, not the speed at which your modem communicates with another
modem. When V.42bis data compression is enabled, you must have a serial port baud rate four
times the transmission speed of the modem to fully optimize compression. So if your UART is fast
enough, you should set the serial port baud rate to a minimum of four times the top speed of your
modem.
If you have an 8250 UART, your most reliable serial port speed will be 9600 bps; if you have an
8250A or a 16450 UART, try 19,200 bps; if you have a 16550 UART or equivalent, a serial port
setting of 115,200 bps can be set reliably.
3.9.1 Configuring Software for the Remote System
You must meet the requirements of the remote system for successful communications. Though the
modem can automatically match the speed of the other modem, you must specify parameters such
as type of flow control, break length, number of data bits, number of stop bits, and parity. If you set
these parameters incorrectly with the remote system, gibberish will appear on your screen.
3.9.2 Terminal Emulation
If you are accessing the remote computer as if from an on-site terminal, the keyboard codes used by
your computer may not match the ones used by the remote computer. To be compatible with the
remote computer, your software must be able to substitute the appropriate codes in what is known as
terminal emulation. Most communications programs can emulate the most common mainframe
terminals, including the DEC VT100, VT102, and VT52 terminals, and the basic TTY mode. If in
doubt about which to choose for a BBS, try ANSI or VT100 first.
3.9.3 File Transfer Protocols
When you upload or download files with your modem, the host computer will ask which file transfer
protocol you want to use. Most communications programs allow you to choose a default protocol.
Your software’s documentation should list the ones it can use (not all communications programs
support all protocols). Zmodem is the recommended protocol for most transfers.