Introduction

You can create custom blocks whose properties and behaviors are defined by M-file functions called M-file S-functions. The Level-2 M-file S-function application programming interface (API) allows you to create blocks that have many of the features and capabilities of Simulink built-in blocks, including:

• Multiple input and output ports

• 1-D, 2-D, and n-D input and output signals

• All data types supported by the Simulink software

• Real or complex signals

• Frame-based signals

• Multiple sample rates

• User-defined data and work vectors

• Tunable and run-time parameters

Note   Level-2 M-file S-functions do not support zero-crossing detection.

For information on how to write a Level-2 M-file S-functions, see Writing Level-2 M-File S-Functions.

Note   This version of the Simulink software also supports a predecessor API known as the Level-1 M-file S-function. This ensures that you can simulate models developed with earlier releases that use Level-1 M-file S-functions in their S-Function blocks (see Maintaining Level-1 M-File S-Functions). Level-1 M-file S-functions support a much smaller subset of the S-function API then Level-2 M-file S-functions, and their features are limited compared to built-in blocks. Use the Level-2 API, not the Level-1 API, to develop new M-file S-functions.

Writing S-Functions in M

Writing Level-2 M-File S-Functions

Related Products & Applications

• Simulink
• Control Design
• Signal Processing & Communications
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