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TOTE-A-FAX 542
4.1 The Basics of Modem Operation
After you’ve connected your Tote-A-
Fax 542 modem to your personal
computer, you need to establish a
procedure to communicate
(exchange data) with a data modem
in another location.
You now have the hardware
connected: on your end you have
the Tote-A-Fax 542 modem linked to
your PC; on the other (remote) end
there should be a modem attached
to another PC. Each modem is
attached to a telephone line.
A telephone call can be placed
between the two modems over the
telephone line. Once the modems
establish a connection, they need a
common set of parameters (rules
and limits) to exchange data bits.
This is the data communications
protocol.
4.2 Giving Commands to a Modem
Finally, you need a way to “talk” to
your modem through your
computer. You can use the:
• command code for the modem;
learning code is a difficult and
time consuming task.
• Standard AT Command Set to
issue commands to the modem.
The Standard AT Command Set is a
simplified “modem language”
supported by a majority of today’s
modems. It consists of short
groupings of keyboard characters,
followed by a carriage return or
enter key. Each character or
character group represents a
command or series of commands.
Pressing the return key initiates the
command you’ve stated to the
modem. This method of telling your
modem to do certain functions is
quick, simple, and easier to use than
command code.
The Tote-A-Fax 542’s built-in
command set is very compatible with
the Standard AT Command Set. It is
an asynchronous commu-nication
program that you can learn with
little effort. It will let you take
control of your modem through
your PC’s keyboard. The commands
are short, simple, and fast.
4.0 OPERATION
