S-Functions

Develop S-function to represent external code and inline S-function with Target Language Compiler (TLC) block target file

An S-function is a computer language description of a Simulink^® block written in MATLAB^®, C, C++, or Fortran. You can develop an S-function to represent external code using an API that interacts with the Simulink engine. Use this S-function with the code generator to produce code. Start with S-Functions and Code Generation.

Blocks

Generated S-Function

Represent model or subsystem as generated S-function code

Topics

Write S-Functions

S-Functions and Code Generation
Use S-functions to extend Simulink support for simulation and code generation.
Build Integrated Code Within the Simulink Environment
Add support files and control model code generation and builds within the Simulink Environment.
Write Noninlined S-Function
Implement your algorithm according to the S-function API by writing a C or C++ MEX S-function.
Write Wrapper S-Function and TLC Files
Create S-functions that serve as wrappers for existing code.
Write Fully Inlined S-Functions

Inline your algorithm in the TLC file for code generation.
Write Fully Inlined S-Functions with mdlRTW Routine
Use the mdlRTW callback method in an inlined S-function.
Accelerate Simulation, Reuse Code, or Protect Intellectual Property by Using S-Function Target
Generate a shared library from a model or subsystem that you can load dynamically into another application.

Legacy Code Tool

Import Calls to External Code into Generated Code with Legacy Code Tool
Import calls to external code for utility functions, lookup tables, filters, and device drivers into the Simulink environment for simulation and code generation.
Legacy Code Tool Examples
Learn how to use the Legacy Code Tool to generate fully inlined C MEX S-functions for legacy or custom code.

S-Function Builder Block

Generate S-Function from Subsystem
Apply Generate S-Function operation to create an S-Function from a subsystem block.
Use a Bus Signal with S-Function Builder to Create an S-Function
Learn how to use a bus signal with a S-Function Builder block.

Featured Examples

Integrate External C Functions That Pass Input and Output Arguments as Parameters with a Fixed-Point Data Type

Integrate legacy C functions that pass their inputs and outputs by using parameters of a fixed-point data type with the Legacy Code Tool.

Open Script

Integrate External C Functions That Implement N-Dimensional Table Lookups

Integrate legacy C functions that implement N-dimensional table lookups by using the Legacy Code Tool.

Open Script