Huawei EM770W At Command Interface Specification page 162

commands defined by manufacturers begin with "%". All extended commands and
manufacturer-defined commands are divided into two categories: Action command
and parameter command.
Action commands
Action commands are the commands that carry out a specific action rather than only
dealing with local parameters of the MS, e.g. AT+CCFC, AT+CMGS. An action
command may carry parameters or not. Action commands include EXECUTION and
TEST.
z
Command format:
No parameter
With 1 parameter
With more parameters <name>[=<compound_value>]
<compound_value> indicates multiple parameters, separated by "," in the middle. For
the parameters that have a default value, they can be omitted and substitute the
default value. If all the parameters are omitted, the "=" behind <name> should be
omitted too. If <name> is not identified, it indicates that this command does not exist,
and the information "COMMAND NOT SUPPORT" will be returned. If <name> is
identifiable, and the command contains uncalled-for parameters, or the number of
parameters goes beyond the defined range, the information "TOO MANY
PARAMETERS" will be returned.
z
Command format:
<name>=?
If the MS cannot identify <name>, the information "COMMAND NOT SUPPORT" will
be given. If the MS can identify <name>, and the command carries no parameter, the
information "OK" will be returned. If the command carries parameters, the value range
of each parameter will be returned first, then "OK" will be returned.
Parameter commands
Parameter commands refer to the commands that can only deal with the local
parameters of MS. These parameters may affect the execution of the action
commands. Parameter commands include SET, READ and TEST commands.
z
Command format:
With 1 parameter:
With more parameters <name>[=<compound_value>]
The SET command is used to set the parameters. <compound_value> means multiple
parameters, separated by "," in the middle. For the parameters that have a default
value, they can be omitted and substitute the default value. If all the parameters are
omitted, the "=" behind <name> should be omitted too. If <name> is not identified, it
Issue 18 (2009-06-22)
EXECUTION command
<name>
<name>[=<value>]
TEST command
SET command
Commercial in Confidence
HUAWEI UMTS M2M Module V100R001
<name>[=<value>]
AT Command Interface Specification
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