Non-static tunable parameters in C++ class code generation.

Hello,

I use Simulink Coder and Embedded Coder to auto-generate a C++ class from a Simulink model. The Simulink model contains only Simulink function blocks (Simulink/User-Defined Functions/Simulink Function) on the root level. The C++ class is instantiated several times from a C++ wrapper and its functions (Simulink function blocks) are called. A parameter structure with a bus data type in the base workspace is used to parametrize the Simulink function blocks. The storage class of the parameter structure is set to Model default.

The code generation uses the following settings:

• Code interface packaging: C++ class
• Parameter visibility: public

In MATLAB R2018b the generated C++ class contains:

// Class declaration for model Test
class TestModelClass {
    // public data and function members
  public:
    // Tunable parameters
    P_Test_t Test_P;

In MATLAB R2019a the generated C++ class contains:

// Class declaration for model Test
class TestModelClass {
    // public data and function members
  public:
    // Tunable parameters
    static P_Test_t Test_P;   

The only difference is the static keyword for the tunable parameters.

As a result, I cannot change the tunable parameters for a single instance, since the parameters are declared as static and, therefore, shared across all instances. Is there a possibility to avoid the static keyword or should I use a different approach in MATLAB R2019a?

Thx for helping...

[db1024]

Would it be possible to use a custom storage class for this purpose?

[db1024]

I updated the release of this question to R2020a, since the issue exists in R2019a, R2019b, and R2020a.

[db1024]

The question has been (re-)published by the MathWorks Support Team on 10 May 2019:

https://de.mathworks.com/matlabcentral/answers/461376-does-embedded-coder-support-instance-specific-parameters-for-top-model-when-generating-c-code

[Carlos Ma]

@db1024 Hey man I came across the same problem too. Have you found a solution yet?

[db1024]

Not yet, but MathWorks told me that the possibility for non-static tunable parameters will be implemented in an upcoming release.

[Carlos Ma]

@db1024 thanks mate

can't believe this feature didn't come by default

[db1024]

I updated the release of this question to R2020b, since the issue exists in R2019a, R2019b, R2020a, and R2020b.

[db1024]

Another question has been (re-)published about this issue by the MathWorks Support Team on 30 Jan 2020:

https://de.mathworks.com/matlabcentral/answers/514023-how-to-make-workspace-variables-appear-as-class-members-of-a-c-class-in-generated-code

Answer 1

[David Balbuena]

Generating non-static parameters is supported starting in R2021a. See this post for instructions on how to configure the model: https://www.mathworks.com/matlabcentral/answers/461376-does-embedded-coder-support-instance-specific-parameters-for-top-model-when-generating-c-code