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AT C ommands
To access the Modem manually, use AT commands.AT commands can be sent to
the Modem from a computer running a communications program.
Command Format
All commands must begin with the AT prefix,followed by the parameter,and end-
ing by pressing the Enter key on the keyboard.All commands can be entered in
either all upper– or all lower–case,but not upper– and lower–case mixed together.
A command entered without any parameters automatically specifies the same com-
mand with a parameter of“0.” The maximum length of a command is eight (8)
characters.The Modem does not count the AT prefix,carriage returns, or spaces.
For example,entering the command
ATH
causes the modem to hang up.
Basic AT Commands
In the following lists, the commands are in bold text,followed by a short function-
al description.Default settings are noted with an asterisk (*).
A/ Repeat last command (do not precede this command with AT
or follow by pressing the Enter key)
AAnswer
D_ Dial command
PSelect pulse dialing (affects current and subsequent dialing)
TSelect tone dialing (affects current and subsequent dialing)
En Command echo
E0 Disables echo
E1 Enables echo*
Hn Switch hook control
A