Best way to call embedded C library function from Simulink model (new to Simulink)

I've read through a lot of the Help contents regarding interfacing with external code (S-functions, legacy code tool, Matlab coder.ceval function in a Matlab function block, etc) and cannot seem to find what I'm looking for. Any help would be appreciated.

Here's what I want to do...

1) Generated embedded code to call a prebuilt C embedded library function. I don't have the C source code. 2) For simulation purposes, I would like to implement this function in Simulink.

Something like...

if (simulation is active) // execute Simulink block else if (code generation active) // call C function from embedded libary else // should not occur endif

I'm sure there's some well established way of doing this, it just isn't obvious to me from the help menus.

Thanks for any help.

Answer 1

[Kaustubha Govind]

I don't know if this is the "best" way to achieve what you need, but one way I can think of is to use the Environment Controller block - to the "Sim" input, connect your Simulink block based implementation, to the "Coder" input, connect an Embedded MATLAB containing a call that looks like this:

   function y = mylibcall(u)
   %#codegen
   y = 0;
   if ~isempty(coder.target)
     y = coder.ceval('sin', u);
   end

EDIT:

It just occurred to me that Variant Subsystems might be the most elegant solution here. You just need to change a workspace variable to flag which subsystem you want to use before simulation or code generation.