Comtrol AT Commands for SmartACFL - Manual (Page 16)

Command Reference Manual
2-4 Conexant 100722A
2.4.2.3 Compound Values
Actions may have more than one subparameter associated with them, and parameters may have more than one value. These
are known as "compound values", and their treatment is the same in both actions and parameters.
A compound value consists of any combination of numeric and string values (as defined in the description of the action or
parameter). The comma character must be included as a separator, before the second and all subsequent values in the
compound value. If a value is not specified (i.e., defaults assumed), the required comma separator must be specified;
however, trailing comma characters may be omitted if all associated values are also omitted.
2.4.3 Action Commands
2.4.3.1 Action Execution Command Syntax
There are two general types of action commands: those that have associated subparameter values that affect only that
invocation of the command, and those that have no subparameters.
If subparameters are associated with a command, the definition of the action command indicates, for each subparameter,
whether the specification of a value for that subparameter is mandatory or optional. For optional subparameters, the definition
indicates the assumed (default) value for the subparameter if no value is specified for that subparameter; the assumed value
may be either a previous value (i.e., the value of an omitted subparameter remains the same as the previous invocation of the
same command, or is determined by a separate parameter or other mechanism), or a fixed value (e.g., the value of an
omitted subparameter is assumed to be zero). Generally, the default value for numeric subparameters is 0, and the default
value for string subparameters is "" (empty string).
The following syntax is used for actions that have no subparameters:
+<name>
The following syntax is used for actions that have one subparameter:
+<name>[=<value>]
The following syntax is used for actions that have two or more subparameters:
+<name>[=<compound_value>]
For actions that accept subparameters, if all subparameters are defined as being optional, and the default values for all
subparameters are satisfactory, the data terminal equipment (DTE) may use the first syntax above (i.e., omit the "=" from the
action execution command as well as all of the subparameter value string).
If all other relevant criteria are met (e.g., the modem is in the proper state), the command is executed with any indicated
subparameters. If <name> is not recognized, the modem issues the ERROR result code and terminates processing of the
command line. An ERROR is also generated if a subparameter is specified for an action that does not accept subparameters,
if too many subparameters are specified, if a mandatory subparameter is not specified, if a value is specified of the wrong
type, or if a value is specified that is not within the supported range.
2.4.3.2 Action Test Command Syntax
The DTE may test if an action command is implemented in the modem by using the syntax:
+<name>=?
If the modem does not recognize the indicated name, it returns an ERROR result code and terminates processing of the
command line. If the modem does recognize the action name, it returns an OK result code. If the named action accepts one
or more subparameters, the modem sends an information text response to the DTE, prior to the OK result code, specifying
the values supported by the modem for each such subparameter, and possibly additional information. The format of this
information text is defined for each action command.
2.4.4 Parameter Commands
2.4.4.1 Parameter Types
Parameters may be defined as "read-only" or "read-write". "Read-only" parameters are used to provide status or identifying
information to the DTE, but cannot be set by the DTE; attempting to set their value is an error. In some cases (specified in the
description of the individual parameter), the modem may ignore attempts to set the value of such parameters rather than
respond with an ERROR result code, if the continued correct operation of the interface between the modem and DTE will not
be affected by such action. Read-only parameters may be read and tested.
"Read-write" parameters may be set by the DTE, to store a value or values for later use. Read-write parameters may be set,
read, and tested.
Parameters may take either a single value, or multiple (compound) values. Each value may be either numeric or string; the
definition of the parameter will specify the type of value for each subparameter. Attempting to store a string value in a numeric
parameter, or a numeric value in a string parameter, is an error.