SARA-R4/N4 series - AT Commands Manual
UBX-17003787 - R09
1 AT command settings
Page 12 of 307
The command description defines each named parameter with its type, its range (valid / acceptable values),
the default value (when available) and the factory-programmed value (when applicable).
For default value it is intended the value automatically set if the parameter is omitted and at the module
power-on (if the command setting is not stored in NVM/profile). For factory-programmed value it is intended
the value set at the module power-on when the setting is not modified respect with the manufacturer setting;
it is valid for the commands that store the setting in NVM/profile.
The summary table on the top of each command section and the
lists all the u-blox cellular modules
that support that command.
The example provided in the command description refers only to the handling provided by the command.
It may be not valid for all the products which the document is applied to. The list of allowed values for a
specific product is provided in the corresponding "Defined values" section.
In this document <CR><LF> are intentionally omitted in the command syntax.
If a parameter is omitted, no value will be inserted between the two commas indicating the interested
parameter in the command line sent by the DTE.
1.1.3 Default values
If the command parameters are optional, they can be left out in the command line. If not otherwise specified,
the default values are assumed as follows:
• For parameters of type Number, the default value is 0
• For parameters of type String, the default value is an empty string
1.1.4 Command line
The AT commands are typically issued to the cellular modules using a command line with the following generic
syntax:
"AT"<command_name><string><S3_character>
Where:
• "AT": prefix to be set at the beginning of each command line
• <command_name>: command name string; it can have a "+" character as prefix
• <string>: string consisting of the parameters value following the syntax provided in this manual
The following rules are used when describing the command syntax:
o <...>: the name in angle brackets is a parameter. The brackets themselves do not appear in the command
line
o [...]: the square brackets represent the optional parameters of a command or an optional part of the DCE
information text response. Brackets themselves do not appear in the command line. When a parameter
is not given, the value will be set to the default value provided in the command description
Parameter types:
o Number: positive and negative counting numbers, as well as zero {..., -2, -1, 0, 1, 2,...}.
o String: sequence of characters enclosed within quotation marks (" ").
• <S3_character>: command line termination character; the factory-programmed termination character is
<CR>
The maximum length of the command line is the maximum number of characters which can be accepted
on a single command line (including the command line termination character).
The command line is not case sensitive unless autobauding is enabled; in this case the prefix "AT" must
be typed either as "AT" or "at"; other combinations ("aT" or "Ta") are not allowed.
When writing or sending an SMS, Ctrl-Z or ESC terminates the command; <CR> is used between the two
parts of the SMS (address and text).
The serial interface driver generally does not allow a new command until the previous one has been terminated
by "OK" final result code or by an error result code. In specific cases (see the abortability attribute), the
command execution may be aborted if a character is sent to DCE before the command has ended.
