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S-Function Builder

Integrate C or C++ code to create S-functions

  • Library:
  • Simulink / User-Defined Functions

  • S-Function Builder block

Description

The S-function builder integrates new or existing C or C++ code and creates a C MEX S-function from specifications you provide. See Use a Bus Signal with S-Function Builder to Create an S-Function for detailed instructions on using the S-Function Builder block to generate an S-function.

Instances of the S-Function Builder block also serve as wrappers for generated S-functions in Simulink® models. When simulating a model containing instances of an S-Function Builder block, Simulink software invokes the generated S-function in order to call your C or C++ code in the instance's mdlStart, mdlOutputs, mdlDerivatives, mdlUpdate and mdlTerminate methods. To learn how Simulink engine interacts with S-functions, see Simulink Engine Interaction with C S-Functions.

Note

The S-Function Builder block does not support masking. However, you can mask a Subsystem block that contains an S-Function Builder block. For more information, see Dynamic Masked Subsystem.

Ports

Input

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The S-Function Builder can accept and complex, 1-D, or 2-D signals and nonvirtual buses. For each of these cases, the signals must have a data type that Simulink supports.

For more information, see Data Types Supported by Simulink in the Simulink documentation.

Data Types: single | double | int8 | int16 | int32 | int64 | uint8 | uint16 | uint32 | uint64 | Boolean | fixed point | enumerated | bus

Output

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The S-Function Builder can output complex, 1-D, or 2-D signals and nonvirtual buses. For each of these cases, the signals must have a data type that Simulink supports.

For more information, see Data Types Supported by Simulink in the Simulink documentation.

Data Types: single | double | int8 | int16 | int32 | int64 | uint8 | uint16 | uint32 | uint64 | Boolean | fixed point | enumerated | bus

Parameters

See Build S-Functions Automatically Using S-Function Builder for information on parameters on the S-Function Builder editor.

Block Characteristics

Data Types

Boolean | double | fixed point | integer | single

Direct Feedthrough

no

Multidimensional Signals

yes

Variable-Size Signals

no

Zero-Crossing Detection

no

Extended Capabilities

Fixed-Point Conversion
Design and simulate fixed-point systems using Fixed-Point Designer™.

Introduced before R2006a