User guide

Developers guidelines | AT commands
18 June 2010
Operating the AT commands
In command mode, the following types of commands can be issued:
• A set command to adjust the operating parameters of the built-in modem
• An execution command to direct action without any need for parameters
• A read command to view the current command settings
• A test command to view the available command parameters
Not all AT commands support all functions listed above. The descriptions in “AT
commands” on page 27 list the functions available for each AT command.
1. Entering a set command
The standard format for entering a set command is:
Note: All command lines are completed by pressing the <CR> key on the computer
keyboard. For the remainder of this manual, appropriate use of the <CR> key is
assumed.
To set the built-in modem to operate with autobaud over an asynchronous connection,
the command line would be:
AT+CBST=0,0,1
However, many commands also have default values. For example, the above
command can be entered as:
AT+CBST=,,1
Default values used by the commands are indicated by bold text in the following
descriptions.
When the parameter is a character string, for example, “<name>”, then the value
should be entered between quotes, for example, “Peter”.
Optional parameters are shown in square brackets, for example, [<value>].
AT<command>=<parameters><CR>
where AT Notifies the built-in modem that a command is being entered.
<command> The name of the command being entered.
<parameters> The values to be used by the command.
<CR> All command lines are terminated by pressing the <CR> (Return or Enter) key.