Documentation

Choose Customization Options for Parameters

By default, parameters in a model appear in generated code as fields of global data structures named:

Based on your code interface requirements, decide whether to customize generation of parameter data. If you do not configure customizations, the code generator determines whether to eliminate or change the representation of parameters in generated code for optimization purposes. If you configure customizations, decide:

Other considerations for model parameters include whether to:

For a list of interface requirements that are relevant to parameters that have corresponding storage classes and storage class properties, see Choose Storage Class and Storage Class Properties for Data Stores.

Parameter requirements for example model rtwdemo_configinterface are:

For this example, configure model parameters and model parameter arguments in rtwdemo_configinterface to meet these code generation requirements.

Configure Default Code Generation Settings for Parameters

Default code generation settings for parameters can reduce the effort of preparing a model for code generation, especially if a model has a significant number of parameters with which you need to interact while the generated code executes. Choose configuration settings once, and the code generator applies those settings to parameters across the model. Simulink^® stores the default configuration as part of the model.

Consider configuring default code generation settings for model parameters if your model uses multiple parameters for the same category that do not have unique requirements or use a shared Embedded Coder Dictionary.

This example shows how to use the Code Mappings Editor to configure default settings for model parameters and model parameter arguments for the model rtwdemo_configinterface. Configure model parameters so that they are tunable and are defined and declared in the generated code as separate global variables that have type qualifiers const and volatile. Configure model parameter arguments to use default settings, where the code generator allocates an area of memory represented as a uniquely named field in an exported structure for each argument instance.

Configure Code Generation for Individual Parameters

You can configure individual parameters for code generation. For example, if a model has two parameters of the same category that have unique code generation requirements, configure the parameters individually. Or, if you configure default settings for a category of parameters, you can override those settings for specific parameters.

If your model meets at least one of these criteria, consider configuring code generation settings for parameters individually:

This example shows how to use the Code Mappings editor to apply your default storage class setting for model parameters to parameters K1, Table1, and Table2 in model rtwdemo_configinterface. You configure code identifiers for those parameters and for model parameter arguments LOWER and UPPER. You can specify code generation identifiers, for example for integration, without modifying the model design.

Organize Parameter Data into a Structure by Using Struct Storage Class

This example shows how to use the Struct storage class to organize block parameter values into a structure in the generated code. You apply the storage class directly to individual data items in a model.

To create a custom structure of parameter data in the generated code, consider creating a corresponding structure in Simulink. See Organize Data into Structures in Generated Code.

/* Type definition for custom storage class: Struct */
   typedef struct my_struct_tag {
      real_T p1;
      real_T p2;
      real_T p3;
   } my_struct_type;

/* Definition for custom storage class: Struct */
my_struct_type my_struct = {
     /* p1 */
     1.0,

     /* p2 */
     2.0,

     /* p3 */
     3.0
};

Configure Code Generation Settings for Parameters Programmatically

To automate configuration of parameters for code generation, use the programming interface for code mappings. For example, when creating custom block libraries or part of an application test environment, use the programming interface to automate data configuration.

This example shows how to configure default settings for model parameters and model parameter arguments for model rtwdemo_configinterface. Configure model parameters so that they are tunable and are defined and declared in the generated code as separate global variables that have type qualifiers const and volatile. Configure model parameter arguments to use default settings, where the code generator allocates an area of memory represented as a uniquely named field in an exported structure for each argument instance. Apply your default storage class setting for model parameters to parameters K1, Table1, and Table2. Configure code identifiers for those parameters.

Choose Storage Class and Storage Class Properties for Model Parameters

Depending on your code generation requirements, choose from these storage classes to configure code generation for model parameters. For constants, only Default applies. For model parameter arguments, only Auto, Default, and Model default apply.

The list of available storage classes might include other project-specific storage classes defined in an Embedded Coder Dictionary. If you have special requirements that are not met by the listed storage classes and you have Embedded Coder software, you can define a storage class. See Define Storage Classes, Memory Sections, and Function Templates for Software Architecture.

For an individual model parameter, use the Identifier storage class property to configure a name for the variable representing the parameter in the generated code. With Embedded Coder, depending on the storage class that you choose, you can also configure these properties.