How to call API in simulink?

I have a c code as follows # include "dfg_uu_file.h" extern double dfg_uu_getmaxsize_a(void)

how to call this using an API in simulink? given that a=[1 2]

Answer 1

[Shaunak]

Hi @sneha bharadwaj,

It is my understanding that you want to call a C function from within Simulink using the S-Function Builder block, where your C code includes a header file and returns a double.

To achieve this, follow these steps:

• Add an S-Function Builder block to your Simulink model (found under User-Defined Functions in the Simulink Library Browser).
• Double-click the block to open the configuration editor:

1. Under the "Inputs" tab, no input is needed since your function has no arguments.
2. Under the "Outputs" tab, define one output port, e.g., y, with:

- Port Name: y

- Port Width: 1

- Data Type: double

• Go to the "Data Properties" tab and add the line mentioned below to the "Include" section:

#include "dfg_uu_file.h"

• Under the "Outputs" section, add the function call:

y[0] = dfg_uu_getmaxsize_a();

• Click "Build" to generate the S-function.
• Use the generated block in your model—this will now call your external C function during simulation.

For more information, kindly refer to the following MathWorks documentation on the S-function Builder Block:

https://www.mathworks.com/help/simulink/slref/sfunctionbuilder.html

Hope this helps!