Rainbow Electronics GM862-QUAD-PY - Manual (Page 10)

AT Commands Reference Guide
80000ST10025a Rev. 5 - 09/07/08
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If all the subparameters of a parameter type command +CMD (or #CMD or $CMD) are
optional, issuing AT+CMD=<CR> (or AT#CMD=<CR> or AT$CMD=<CR>) causes the OK
result code to be returned and the previous values of the omitted subparameters to be
retained.
3.2.1 String Type Parameters
A string, either enclosed between quotes or not, is considered to be a valid string type parameter
input. According to V25.ter space characters are ignored on the command line and may be used freely
for formatting purposes, unless they are embedded in numeric or quoted string constants; therefore a
string containing a space character has to be enclosed between quotes to be considered a valid string
type parameter (e.g. typing AT+COPS=1,0,”A1” is the same as typing AT+COPS=1,0,A1; typing
AT+COPS=1,0,”A BB” is different from typing AT+COPS=1,0,A BB).
When #SELINT=0 (or 1) mode is selected, a string not enclosed between quotes is changed in upper
case (e.g. mickey become MICKEY), while a string enclosed between quotes is case sensitive.
When #SELINT=2 mode is selected, a string enclosed between quotes is case sensitive.
A small set of commands requires always to write the input string parameters within quotes: this is
explicitly reported in the specific descriptions.
3.2.2 Command Lines
A command line is made up of three elements: the prefix, the body and the termination character.
The command line prefix consists of the characters “AT” or “at”, or, to repeat the execution of the
previous command line, the characters “A/” or “a/”.
The termination character may be selected by a user option (parameter S3), the default being <CR>.
The basic structures of the command line are:
• ATCMD1<CR> where AT is the command line prefix, CMD1 is the body of a basic command (nb:
the name of the command never begins with the character “+”) and <CR> is the command line
terminator character
• ATCMD2=10<CR> where 10 is a subparameter
• AT+CMD1;+CMD2=, ,10<CR> These are two examples of extended commands (nb: the name
of the command always begins with the character “+” 2 ). They are delimited with semicolon. In the
second command the subparameter is omitted.
• +CMD1?<CR> This is a Read command for checking current subparameter values
• +CMD1=?<CR> This is a test command for checking possible subparameter values
These commands might be performed in a single command line as shown below:
2 The set of proprietary AT commands differentiates from the standard one because the name of each of them
begins with either “@”, “#”, “$” or “*”. Proprietary AT commands follow the same syntax rules as extended
commands