Owner`s manual

15
3 - AT Commands, S-Registers and Result Codes
Chapter 3 - AT Commands, S-Registers
and Result Codes
Introduction
This chapter describes how to use MT3400ZLX AT
commands, S-Registers and Result Codes.
How To Use AT Commands
Usually, your fax and data comm software controls
the modem for you. However, you may also want to
use the AT commands. These commands give you
complete control over your modem. You need to be
careful when using these commands, because they
can cause your software to loose its ability to control
the modem. If you do find that an AT command has
caused a problem, then turn the computer off and
then back on. That will reset most AT commands to
the factory default settings. You can also type
AT&F&WZ to go back to the factory default setting.
To use an AT command, you must first:
1. Run your communication software.
2. Configure the software for the appropriate COM
port and
IRQ settings, if necessary.
3. Enter Terminal mode (also i.e., “Command
mode”, “Local mode”, or “Direct mode”). This is
the mode in which most data comm software
packages start up. You can then type the
desired AT command, then press the Enter key.