How we have define a parameter for Code Generation

I've added 2 constant blocks.

As you can see the model explorer defines.

I couldn't understand, if we add outport the constant name is generated in code, if there is no outport for parameter2 it will not generated in C code.

How I solve the problem.

Generated Code:

/* Definition for custom storage class: Define */

#define parameter1 1.0 /* Referenced by: '<Root>/Constant' */

Thank you.

Answer 1

[Shubham]

Hi Ali,

When working with Simulink models and generating C code, only the parameters that are actively used in the mode - like those connected to an "Outport", are typically included in the generated code. This behaviour is because Simulink's Code Generation optimizes the code by omitting unused variables or constants to reduce memory usage and improve efficiency.

In your case, you’ve noticed that the "Constant" block without an "Outport" doesn’t result in the parameter being included in the generated C code. The generated code only includes "parameter1" because it is referenced by an "Outport". The "model_name.h" file shows this as comment in generated C code:

/*-
 * These blocks were eliminated from the model due to optimizations:
 *
 * Block '<Root>/parameter2' : Unused code path elimination
 */

For more information on how dead code paths and unused blocks are eliminated from generated code, refer to the following documentation link:

https://mathworks.com/help/rtw/ug/eliminate-dead-code-paths-in-generated-code.html

Hope it helps.

[Ali]

Hi, Shubham,

Thanks for reply,

in which cases it does not optimize?

Can I turn off the optimization to test under some conditions?

Thanks.

[Shubham]

Hi Ali,

For Code Generation, block reduction optimization removes all diagram branches terminating in sink blocks that do not participate in code generation.

To turn off the optimization, navigate to "Model Settings" -> "Simulation Target" and uncheck "Block reduction" property.

For more information on "Block reduction", refer to the following documentation link:

https://mathworks.com/help/simulink/gui/blockreduction.html

If you have any other query, feel free to comment.

Thanks