How to create a S-function for targetlink generated code .

I tried legacy tool for generating S-function which I was able to do .

eg. when I have a function with input parameters and return type well defined there is no issue .

When the function looks like this==>int sum (int a, int b) inside sum.c.

But in Targetlink generated code the main function is a void function.

eg. void sum (void), where i am struggling to create S-Function.

Can you please let me know any workaround for the same.

Regards

Sumit

Answer 1

[arushi]

Hi Sumit,

You may try creating an S-Function by managing the inputs and outputs through global variables or by wrapping the void function to fit the S-Function interface.Workaround Steps

1. Wrap the void Function: Create a wrapper function that takes inputs and returns outputs, and inside this wrapper, call the original void function. The wrapper function will handle the interaction with the S-Function.
2. Define Global Variables: Use global variables to pass inputs to the void function and retrieve outputs from it.
3. Create the S-Function: Use the legacy code tool to create the S-Function for the wrapper function.

Hope this helps.

Answer 2

[Sahas]

Hi @Sumit,

As per my understanding of the question, you would like a way to generate “S-function” using “legacy tool” for a function whose “return” and “argument” parameters are of “void” type.

I was able to create a small example for this, please follow the steps below to create the “S-function” with required specifications:

• Create two code files named "sum.c" and "sum.h" that contain a void function and the headers, respectively.

• Generate the S-function using “legacy code tool”.

• A Simulink model will open with the required “void” type block.

To know more about using the “legacy code tool”, it’s integration with C/C++ code and a few examples, refer to the following documentation links:

• https:/www.mathworks.com/help/simulink/slref/legacy_code.html
• https://www.mathworks.com/help/simulink/sfg/integrating-existing-c-functions-into-simulink-models-with-the-legacy-code-tool
• https://www.mathworks.com/help/rtw/ug/legacy-code-tool-examples.html

I hope this is beneficial!