Huawei MC509 manual 2shows the basic organization format of the AT command line, Prefixed with +

HUAWEI MC509 CDMA LGA Module
AT Command Interface Specification	Overall Description

Figure 1-2shows the basic organization format of the AT command line.

Figure 1-2Basic organization format the AT command line

	read command for checking
	current subparameter values
subparameter
command line prefix	extended commands are	command line
	delimited with semicolon	termination character

ATCMD1 CMD2=12; +CMD1; +CMD2=,,15; +CMD2?; +CMD2=?<CR>

		subparameters
basic command		may be omitted
(no + prefix)
	extended command		test command for checking
	(prefixed with +)
			possible subparameter values

The returned value of the AT command consists of two parts: response message and result codes. Figure 1-3shows an example of returned value of the AT command.

Figure 1-3An example of returned value of the AT command

information response to +CMD2=?	also string type subparameters possible
information response to +CMD2?

<CR><LF>+CMD2: 3,0,15,"GSM"<CR><LF> <CR><LF>+CMD2: (0-3),(0,1),(0-12,15),("GSM","IRA")<CR><LF> <CR><LF>OK<CR><LF>

shows acceptable ranges of each subparameter

final result code

1.4.2Types of AT Commands

AT commands are categorized into three types: basic commands, S register commands, and extended and vendor-defined commands.

A basic command starts with a single letter or with the & symbol plus a single letter. Table 1-1describes the format of a basic command.

Issue 01 (2011-08-26)	Huawei Proprietary and Confidential	19
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