Writing S-Functions

Chapter 8
Writing S-Functions for Real-Time Workshop

Introduction

This chapter describes how to create S-functions that work seamlessly with both Simulink and the Real-Time Workshop. It begins with basic concepts and concludes with an example of how to create a highly optimized direct-index lookup table S-function block.

This chapter assumes that you understand these concepts:

• Level 2 S-functions
• Target Language Compiler (TLC)
• The basics of how the Real-Time Workshop creates generated code

See the Target Language Compiler Reference Guide, and the Real-Time Workshop User's Guide for more information about these subjects.

A note on terminology: when this chapter refers actions performed by the Target Language Compiler, including parsing, caching, creating buffers, etc., the name Target Language Compiler is spelled out fully. When referring to code written in the Target Language Compiler syntax, this chapter uses the abbreviation TLC.

Note    The guidelines presented in this chapter are for Real-Time Workshop users. Even if you do not currently use the Real-Time Workshop, we recommend that you follow the guidelines presented in this chapter when writing S-functions, especially if you are creating general-purpose S-functions.

Example - Time Varying Continuous Transfer Function

Classes of Problems Solved by S-Functions