Black Box MD1276A, User Manual

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AT Commands
Page 21
Setting Terminal Speeds
Your modem can sense the terminal speed of the computer and automatically change its terminal
speed to match. This is known as
‘ auto bauding ’ , and is done each time an AT command is
issued to the modem.
Your modem can auto baud at 300 bps through 9600 bps, 14,400 bps, 19,200 bps, 38,400 bps,
57,600 bps and 115,200 bps.
The R command may also be used to disable autobauding and lock the terminal speed. Refer to
the R command for available speeds.
Line Speeds
Connection speeds higher than 33600bps can only be obtained by calling an Internet Service
Provider (ISP) or Central Site which supports the Rockwell K56flex
™ protocol. The speeds at
which you will be able to connect also depend on the quality of the telephone line used when
making the connection.
The B command determines the speed at which your modem connects to another modem. The
listed B commands are provided by your modem.
In most cases you should select B0, as this setting attempts to connect at any speed supported
by the modem.
V.90 & V.34 Typical Settings
Here are some example settings that may be relevant to the way in which you wish to operate
your modem.
Example 1 - Dialling or answering other modems at the highest speed.
B Command Setting: B0
Terminal Speed: 115,200 bps
Flow Control: On (&K3 for RTS/CTS flow control)
Use this arrangement when dialling online information services or bulletin boards. With these
settings, you modem will attempt to connect at any speed from 56,000 bps to 1200 bps. These
are the default settings of your modem.
If you wish your modem to answer incoming calls, use these settings. This will allow your
modem to connect at any speed between 56,000 bps and 300 bps. If you are using a software
program that controls the answering of your modem (as some bulletin board systems do) you
may need to issue an ATS0=0 command to disable auto-answering, otherwise issue ATS0=2 to
make the modem answer calls after two rings (the default setting).