Conventions; At Command Syntax; Using Parameters - Siemens TC37 Module At Command Reference

AT Command Set

1.3 Conventions

Throughout the document, the GSM engines are referred to as ME (Mobile Equipment), MS (Mobile
Station), TA (Terminal Adapter), DCE (Data Communication Equipment) or facsimile DCE (FAX
modem, FAX board). When the Siemens product names are required to distinguish the two models,
TC3x is short for the engine type and TC35T for the terminal.
To control your GSM engine you can simply send AT Commands via its serial interface. The
controlling device at the other end of the serial line is referred to as TE (Terminal Equipment), DTE
(Data Terminal Equipment) or plainly ´the application´ (probably running on an embedded system).

1.4 AT command syntax

The "AT" or "at" prefix must be set at the beginning of each command line. To terminate a command
line enter <CR>.
Commands are usually followed by a response that includes "<CR><LF><response><CR><LF>".
Throughout this document, only the responses are presented, <CR><LF> are omitted intentionally.
Table 2: Types of AT commands and responses
Test command
Read command
Write command
Execution command

1.4.1 Using parameters

· Default parameters are underlined throughout this document.
· Optional parameters are enclosed in square brackets. If optional parameters are omitted, the
current settings are used until you change them.
· Optional parameters or subparamters can be omitted unless they are followed by other
parameters. If you want to omit a parameter in the middle of a string it must be replaced by a
comma. Example:
AT+CPBW=,<number>,<type>,<text> writes a phonebook entry to the first free memory location.
AT+CPBW=<index>,<number>,<type>,<text> writes a phonebook entry to the memory location
specified by <index>.
· When the parameter is a character string, e.g. <text> or <number>, the string must be enclosed in
quotation marks, e.g. "Charlie Brown" or "+49030xxxx". Symbols within quotation marks will be
recognized as strings.
· All spaces will be ignored when using strings without quotaton marks.
· It is possible to omit the leading zeros of strings which represent numbers.
· In case of using V.25ter commands without giving an optional parameter, its value is assumed to
be 0.
TC3X_ATC_01_V04.00
AT+CXXX=? The mobile equipment returns the list of parameters and
value ranges set with the corresponding Write command
or by internal processes.
AT+CXXX? This command returns the currently set value of the
parameter or parameters
AT+CXXX=<...> This command sets user-definable parameter values.
AT+CXXX The execution command reads non-variable parameters
affected by internal processes in the GSM engine.
Page 11 of 204 29.05.2002