S-Function SimStruct Functions

About SimStruct Functions

The Simulink^® software provides a set of functions for accessing the fields of an S-function's simulation data structure (SimStruct). S-function callback methods use these functions to store and retrieve information about an S-function.

Language Support

Some SimStruct functions are available only in some of the languages supported by the Simulink software. The reference page for each SimStruct macro or function lists the languages in which it is available and gives the syntax for these languages.

Note

Most SimStruct functions available in C are implemented as C macros. Individual reference pages indicate any SimStruct macro that becomes a function when you compile your S-function in debug mode (mex -g).

The SimStruct

The file simstruc.h is a C language header file that defines the Simulink data structure and the SimStruct access macros. It encapsulates all the data relating to the model or S-function, including block parameters and outputs.

There is one SimStruct data structure allocated for the Simulink model. Each S-function in the model has its own SimStruct associated with it. The organization of these SimStructs is much like a directory tree. The SimStruct associated with the model is the root SimStruct. The SimStructs associated with the S-functions are the child SimStructs.

SimStruct Macros and Functions Listed by Usage

• Buses

• Data Type

• Dialog Box Parameters

• Error Handling and Status

• Function Call

• Input and Output Ports

• Model Reference

• Run-Time Parameters

• Sample Time

• Simulation Information

• State and Work Vector

• Code Generation

• Miscellaneous

Buses

Macro	Description
ssGetBusElementComplexSignal	Get the signal complexity for a bus element.
ssGetBusElementDataType	Get the data type identifier for a bus element.
ssGetBusElementDimensions	Get the dimensions of a bus element.
ssGetBusElementName	Get the name of a bus element.
ssGetBusElementNumDimensions	Get the number of dimensions for a bus element.
ssGetBusElementOffset	Get the offset from the start of the bus data type to a bus element.
ssGetNumBusElements	Get the number of elements in a bus signal.
ssGetSFcnParamName	Get the value of a block parameter for an S-function block.
ssIsDataTypeABus	Determine whether a data type identifier represents a bus signal.
ssRegisterTypeFromParameter	Register a data type that a parameter in the Simulink data type table specifies.
ssSetBusInputAsStruct	Specify whether to convert the input bus signal for an S-function from virtual to nonvirtual.
ssSetBusOutputAsStruct	Specify whether the output bus signal from an S-function must be virtual or nonvirtual.
ssSetBusOutputObjectName	Specify the name of the bus object that defines the structure and type of the output bus signal.

Data Type

Macro	Description
ssGetDataTypeId	Get the ID for a data type.
ssGetDataTypeIdAliasedThruTo	Get the ID for the built-in data type associated with a data type alias.
ssGetDataTypeName	Get a data type's name.
ssGetDataTypeSize	Get a data type's size.
ssGetDataTypeZero	Get the zero representation of a data type.
ssGetInputPortDataType	Get the data type of an input port.
ssGetNumDataTypes	Get the number of data types defined by an S-function or the model.
ssGetOutputPortDataType	Get the data type of an output port.
ssGetOutputPortSignal	Get an output signal of any type except double.
ssGetSFcnParamDataType	Get the data type of a parameter.
ssRegisterDataType	Register a data type.
ssSetDataTypeSize	Specify the size of a data type.
ssSetDataTypeZero	Specify the zero representation of a data type.
ssSetInputPortDataType	Specify the data type of signals accepted by an input port.
ssSetOutputPortDataType	Specify the data type of an output port.

Dialog Box Parameters

Macro	Description
ssGetDTypeIdFromMxArray	Get the Simulink data type of a dialog parameter.
ssGetNumSFcnParams	Get the number of parameters that an S-function expects.
ssGetSFcnParam	Get a parameter entered by a user in the S-Function block dialog box.
ssGetSFcnParamsCount	Get the actual number of parameters specified by the user.
ssSetNumSFcnParams	Set the number of parameters that an S-function expects.
ssSetSFcnParamTunable	Specify the tunability of a dialog box parameter.

Error Handling and Status

Macro	Description
ssGetErrorStatus	Get a character vector that identifies the last error.
ssGetLocalErrorStatus	Get a character vector that identifies the last error in a thread-safe manner.
ssPrintf	Print a variable-content msg.
ssSetErrorStatus	Report errors.
ssSetLocalErrorStatus	Report errors in a thread-safe manner.
ssWarning	Display a warning message.

Function Call

Macro	Description
ssCallSystemWithTid	Execute a function-call subsystem connected to an S-function.
ssDisableSystemWithTid	Disable a function-call subsystem connected to this S-function block.
ssEnableSystemWithTid	Enable a function-call subsystem connected to this S-function.
ssGetCallSystemNumFcnCall- Destinations	Get the number of function-call destinations.
ssGetExplicitFCSSCtrl	Determine whether this S-function explicitly enables and disables the function-call subsystem that it invokes.
ssSetCallSystemOutput	Specify that an output port element issues a function call.
ssSetExplicitFCSSCtrl	Specify whether an S-function explicitly enables and disables the function-call subsystem that it calls.

Input and Output Ports

I/O Port — Signal Specification

Macro	Description
ssAllowSignalsWithMoreThan2D	Enable S-function to work with multidimensional input and output signals.
ssGetInputPortComplexSignal	Get the numeric type (complex or real) of an input port.
ssGetInputPortDataType	Get the data type of an input port.
ssGetInputPortDirectFeedThrough	Determine whether an input port has direct feedthrough.
ssGetInputPortFrameData	Determine whether a port accepts signal frames.
ssGetInputPortOffsetTime	Determine the offset time of an input port.
ssGetInputPortRequiredContiguous	Determine whether the signal elements entering a port must be contiguous.
ssGetInputPortSampleTime	Determine the sample time of an input port.
ssGetInputPortSampleTimeIndex	Get the sample time index of an input port.
ssGetInputPortUnit	Get unit of input port
ssGetOutputPortComplexSignal	Get the numeric type (complex or real) of an output port.
ssGetOutputPortDataType	Get the data type of an output port.
ssGetOutputPortFrameData	Determine whether a port outputs signal frames.
ssGetOutputPortOffsetTime	Determine the offset time of an output port.
ssGetOutputPortSampleTime	Determine the sample time of an output port.
ssGetOutputPortUnit	Get unit of output port
ssRegisterUnitFromExpr	Register unit from unit expression
ssSetInputPortComplexSignal	Set the numeric type (real or complex) of an input port.
ssSetInputPortDataType	Set the data type of an input port.
ssSetInputPortDirectFeedThrough	Specify that an input port is a direct-feedthrough port.
ssSetInputPortOffsetTime	Specify the sample time offset for an input port.
ssSetInputPortRequiredContiguous	Specify that the signal elements entering a port must be contiguous.
ssSetInputPortSampleTime	Set the sample time of an input port.
ssSetInputPortUnit	Specify unit of input port
ssSetNumInputPorts	Set the number of input ports on an S-Function block.
ssSetNumOutputPorts	Specify the number of output ports on an S-Function block.
ssSetOneBasedIndexInputPort	Specify that an input port expects one-based indices.
ssSetOneBasedIndexOutputPort	Specify that an output port emits one-based indices.
ssSetOutputPortComplexSignal	Specify the numeric type (real or complex) of this port.
ssSetOutputPortDataType	Specify the data type of an output port.
ssSetOutputPortOffsetTime	Specify the sample time offset value of an output port.
ssSetOutputPortSampleTime	Specify the sample time of an output port.
ssSetOutputPortUnit	Specify unit of output port
ssSetZeroBasedIndexInputPort	Specify that an input port expects zero-based indices.
ssSetZeroBasedIndexOutputPort	Specify that an output port emits zero-based indices.

I/O Port — Signal Dimensions

Macro	Description
ssAddOutputDimsDependencyRule	Register a method to handle current dimensions update.
ssAddVariableSizeSignalsRuntimeChecker	Register a method to check the current input dimensions.
ssAllowSignalsWithMoreThan2D	Enable S-function to work with multidimensional signals.
ssGetCurrentInputPortDimensions	Gets the current size of dimension dIdx of input port pIdx.
ssGetCurrentInputPortWidth	Gets the total width (total number of elements) of the signal at input port pIdx
ssGetCurrentOutputPortDimensions	Gets the current size of dimension dIdx of the signal at output port pIdx.
ssGetCurrentOutputPortWidth	Gets the total width (total number of elements) of the signal at output port pIdx.
ssGetInputPortDimensions	Get the dimensions of the signal accepted by an input port.
ssGetInputPortDimensionSize	Get the size of one dimension of the signal entering an input port.
ssGetInputPortDimensionsMode	Gets the dimensions mode of the input port indexed by pIdx,
ssGetInputPortNumDimensions	Get the dimensionality of the signals accepted by an input port.
ssGetInputPortWidth	Determine the width of an input port.
ssGetOutputPortDimensions	Get the dimensions of the signal leaving an output port.
ssGetOutputPortDimensionSize	Get the size of one dimension of the signal leaving an output port.
ssGetOutputPortDimensionsMode	Sets the dimensions mode of the output port indexed by pIdx.
ssGetOutputPortNumDimensions	Get the number of dimensions of an output port.
ssGetOutputPortWidth	Determine the width of an output port.
ssSetCurrentOutputPortDimensions	Sets the current size corresponding to dimension dIdx of the output signal at port pIdx.
ssSetDWorkRequireResetForSignalSize	Set the block flag for resetting the dIndex DWork size upon subsystem reset.
ssSetInputPortDimensionInfo	Set the dimensionality of an input port.
ssSetInputPortDimensionsMode	Sets the dimensions mode of the input port indexed by pIdx.
ssSetInputPortDimsSameAsOutputPortDims	Set the dimensions of output port outIdx to be equal than the dimensions of input port inpIdx.
ssSetInputPortMatrixDimensions	Specify dimension information for an input port that accepts matrix signals.
ssSetInputPortVectorDimension	Specify dimension information for an input port that accepts vector signals.
ssSetInputPortWidth	Set the width of a 1-D (vector) input port.
ssSetOutputPortDimensionInfo	Specify the dimensionality of an output port.
ssSetOutputPortDimensionsMode	Sets the dimensions mode of the output port indexed by pIdx.
ssSetOutputPortMatrixDimensions	Specify dimension information for an output port that emits matrix signals.
ssSetOutputPortVectorDimension	Specify dimension information for an output port that emits vector signals.
ssSetOutputPortWidth	Specify the width of a 1-D (vector) output port.
ssSetOutputPortMatrixDimensions	Specify the dimensions of a 2-D (matrix) signal.
ssRegMdlSetInputPortDimensionsModeFcn	Register the method to handle dimensions mode propagation for each input port.
ssSetSignalSizesComputeType	Set the type of output dependency on the input signal.
ssSetVectorMode	Specify the vector mode that an S-function supports.

I/O Port — Signal Access

Macro	Description
ssGetInputPortBufferDstPort	Determine the output port that is overwriting an input port's memory buffer.
ssGetInputPortConnected	Determine whether an S-Function block port is connected to a nonvirtual block.
ssGetInputPortOptimOpts	Determine the reusability setting of the memory allocated to the input port of an S-function.
ssGetInputPortOverWritable	Determine whether an input port can be overwritten.
ssGetInputPortRealSignal	Get the address of a real, contiguous signal entering an input port.
ssGetInputPortRealSignalPtrs	Access the signal elements connected to an input port.
ssGetInputPortSignal	Get the address of a contiguous signal entering an input port.
ssGetInputPortSignalPtrs	Get pointers to input signal elements of type other than double.
ssGetNumInputPorts	Can be used in any routine (except mdlInitializeSizes) to determine how many input ports a block has.
ssGetNumOutputPorts	Can be used in any routine (except mdlInitializeSizes) to determine how many output ports a block has.
ssGetOutputPortConnected	Determine whether an output port is connected to a nonvirtual block.
ssGetOutputPortBeingMerged	Determine whether the output of this block is connected to a Merge block.
ssGetOutputPortOptimOpts	Determine the reusability of the memory allocated to the output port of an S-function.
ssGetOutputPortRealSignal	Access the elements of a signal connected to an output port.
ssGetOutputPortSignal	Get the vector of signal elements emitted by an output port.
ssSetInputPortOptimOpts	Specify the reusability of the memory allocated to the input port of an S-function.
ssSetInputPortOverWritable	Specify whether an input port is overwritable by an output port.
ssSetOutputPortOptimOpts	Specify the reusability of the memory allocated to the output port of an S-function.
ssSetOutputPortOverwritesInputPort	Specify whether an output port can share its memory buffer with an input port.

Model Reference

Macro	Description
ssRTWGenIsModelReferenceRTWTarget	Determine if the model reference Simulink Coder™ target is generating.
ssRTWGenIsModelReferenceSIMTarget	Determine if the model reference simulation target is generating.
ssSetModelReferenceNormalModeSupport	Specify if S-function can be used in referenced model simulating in normal mode.
ssSetModelReferenceSampleTimeDefaultInheritance	Specify that a referenced model containing this S-function can inherit its sample time from its parent model.
ssSetModelReferenceSampleTimeDisallowInheritance	Specify that the use of this S-function in a referenced model prevents the referenced model from inheriting its sample time from its parent model.
ssSetModelReferenceSampleTimeInheritanceRule	Specify whether use of an S-function in a referenced model prevents the referenced model from inheriting its sample time from the parent model.

Run-Time Parameters

These macros allow you to create, update, and access run-time parameters corresponding to a block's dialog parameters.

Macro	Description
ssGetNumRunTimeParams	Get the number of run-time parameters created by this S-function.
ssGetRunTimeParamInfo	Get the attributes of a specified run-time parameter.
ssRegAllTunableParamsAsRunTimeParams	Register all tunable dialog parameters as run-time parameters.
ssRegDlgParamAsRunTimeParam	Register a run-time parameter.
ssSetNumRunTimeParams	Specify the number of run-time parameters to be created by this S-function.
ssSetRunTimeParamInfo	Specify the attributes of a specified run-time parameter.
ssUpdateAllTunableParamsAsRunTimeParams	Update all run-time parameters corresponding to tunable dialog parameters.
ssUpdateDlgParamAsRunTimeParam	Update a run-time parameter.
ssUpdateRunTimeParamData	Update the value of a specified run-time parameter.
ssUpdateRunTimeParamInfo	Update the attributes of a specified run-time parameter from the attributes of the corresponding dialog parameters.

Sample Time

Macro	Description
ssGetInputPortSampleTime	Determine the sample time of an input port.
ssGetInputPortSampleTimeIndex	Get the sample time index of an input port.
ssGetNumSampleTimes	Get the number of sample times an S-function has.
ssGetOffsetTime	Determine one of an S-function's sample time offsets.
ssGetOutputPortSampleTime	Determine the sample time of an output port.
ssGetPortBasedSampleTimeBlockIsTriggered	Determine whether a block that uses port-based sample times resides in a triggered subsystem.
ssGetSampleTime	Determine one of an S-function's sample times.
ssGetTNext	Get the time of the next sample hit in a discrete S-function with a variable sample time.
ssIsContinuousTask	Determine whether a specified rate is the continuous rate.
ssIsSampleHit	Determine the sample rate at which an S-function is operating.
ssIsSpecialSampleHit	Determine whether the current sample time hits two specified rates.
ssSampleAndOffsetAreTriggered	Determine whether a sample time and offset value pair indicate a triggered sample time.
ssSetInputPortSampleTime	Set the sample time of an input port.
ssSetModelReferenceSampleTimeDefaultInheritance	Specify that a referenced model containing this S-function can inherit its sample time from its parent model.
ssSetModelReferenceSampleTimeDisallowInheritance	Specify that the use of this S-function in a referenced model prevents the referenced model from inheriting its sample time from its parent model.
ssSetModelReferenceSampleTimeInheritanceRule	Specify whether use of an S-function in a referenced model prevents the referenced model from inheriting its sample time from the parent model.
ssSetNumSampleTimes	Set the number of sample times an S-function has.
ssSetOffsetTime	Specify the offset of a sample time.
ssSetSampleTime	Specify a sample time for an S-function.
ssSetTNext	Specify the time of the next sample hit in an S-function.

Simulation Information

Macro	Description
ssGetBlockReduction	Determine whether a block has requested block reduction before the simulation has begun and whether it has actually been reduced after the simulation loop has begun.
ssGetErrorStatus	Get a character vector that identifies the last error.
ssGetFixedStepSize	Get the fixed step size of the model containing the S-function.
ssGetMaxStepSize	Get the maximum step size of the model containing the S-function.
ssGetMinStepSize	Get the minimum step size of the model containing the S-function.
ssGetSimMode	Determine the context in which an S-function is being invoked: normal simulation, external-mode simulation, model editor, etc.
ssGetSimStatus	Determine the current simulation status.
ssGetSolverMode	Get the solver mode being used to solve the S-function.
ssGetSolverName	Get the name of the solver being used for the simulation.
ssGetStateAbsTol	Get the absolute tolerance used by the model's variable-step solver for a specified state.
ssGetStopRequested	Get the value of the simulation stop requested flag.
ssGetT	Get the current base simulation time.
ssGetTaskTime	Get the current time for a task.
ssGetTFinal	Get the end time of the current simulation.
ssGetTNext	Get the time of the next sample hit.
ssGetTStart	Get the start time of the current simulation.
ssIsExternalSim	Determine if the model is running in external mode.
ssIsFirstInitCond	Determine whether the current simulation time is equal to the simulation start time.
ssIsMajorTimeStep	Determine whether the current time step is a major time step.
ssIsMinorTimeStep	Determine whether the current time step is a minor time step.
ssIsVariableStepSolver	Determine whether the current solver is a variable-step solver.
ssRTWGenIsAccelerator	Determine if the model is running in Accelerator mode.
ssSetStateAbsTol	Set the values of the absolute tolerances that the variable-step solver will apply to the S-function states.
ssSetBlockReduction	Request that Simulink attempt to reduce a block.
ssSetOperatingPointCompliance	Specify how Simulink treats an S-function when saving and restoring the simulation state of a model containing the S-function.
ssSetOperatingPointVisibility	Specify whether or not the simulation state of the S-function is visible (accessible) in the simulation state of the model.
ssSetSolverNeedsReset	Ask Simulink to reset the solver.
ssSetStopRequested	Ask Simulink to terminate the simulation at the end of the current time step.

State and Work Vector

Macro	Description
ssGetContStates	Get an S-function's continuous states.
ssGetDiscStates	Get an S-function's discrete states.
ssGetDWork	Get a DWork vector.
ssGetDWorkComplexSignal	Determine whether the elements of a DWork vector are real or complex numbers.
ssGetDWorkDataType	Get the data type of a DWork vector.
ssGetDWorkName	Get the name of a DWork vector.
ssGetDWorkUsageType	Determine how the DWork vector is used in S-function.
ssGetDWorkUsedAsDState	Determine whether a DWork vector is used as a discrete state vector.
ssGetDWorkWidth	Get the size of a DWork vector.
ssGetdX	Get the derivatives of the continuous states of an S-function.
ssGetIWork	Get an S-function's integer-valued (int_T) work vector.
ssGetIWorkValue	Get a value from a block's integer work vector.
ssGetModeVector	Get an S-function's mode work vector.
ssGetModeVectorValue	Get an element of a block's mode vector.
ssGetNonsampledZCs	Get an S-function's zero-crossing signals vector.
ssGetNumContStates	Determine the number of continuous states that an S-function has.
ssGetNumDiscStates	Determine the number of discrete states that an S-function has.
ssGetNumDWork	Get the number of Dwork vectors used by a block.
ssGetNumIWork	Get the size of an S-function's integer work vector.
ssGetNumModes	Determine the size of an S-function's mode vector.
ssGetNumNonsampledZCs	Determine the number of nonsampled zero crossings that an S-function detects.
ssGetNumPWork	Determine the size of an S-function's pointer work vector.
ssGetNumRWork	Determine the size of an S-function's real-valued (real_T) work vector.
ssGetPWork	Get an S-function's pointer (void *) work vector.
ssGetPWorkValue	Get a pointer from a pointer work vector.
ssGetRealDiscStates	Get the real (real_T) values of an S-function's discrete state vector.
ssGetRWork	Get an S-function's real-valued (real_T) work vector.
ssGetRWorkValue	Get an element of an S-function's real-valued work vector.
ssSetDWorkComplexSignal	Specify whether the elements of a Dwork vector are real or complex.
ssSetDWorkDataType	Specify the data type of a Dwork vector.
ssSetDWorkName	Specify the name of a Dwork vector.
ssSetDWorkUsageType	Specify how the DWork vector is used in S-function.
ssSetDWorkUsedAsDState	Specify that a Dwork vector is used as a discrete state vector.
ssSetDWorkWidth	Specify the width of a Dwork vector.
ssSetIWorkValue	Set an element of a block's integer work vector.
ssSetModeVectorValue	Set an element of a block's mode vector.
ssSetNumContStates	Specify the number of continuous states that an S-function has.
ssSetNumDiscStates	Specify the number of discrete states that an S-function has.
ssSetNumDWork	Specify the number of Dwork vectors used by a block.
ssSetNumIWork	Specify the size of an S-function's integer (int_T) work vector.
ssSetNumModes	Specify the number of operating modes that an S-function has.
ssSetNumNonsampledZCs	Specify the number of zero crossings that an S-function detects.
ssSetNumPWork	Specify the size of an S-function's pointer (void *) work vector.
ssSetNumRWork	Specify the size of an S-function's real (real_T) work vector.
ssSetPWorkValue	Set an element of a block's pointer work vector.
ssSetRWorkValue	Set an element of a block's floating-point work vector.

Code Generation

Macro	Description
ssGetDWorkRTWIdentifier	Get the identifier used to declare a DWork vector in code generated from the associated S-function.
ssGetDWorkRTWIdentifierMustResolveToSignalObject	Get a flag indicating if a DWork vector resolves to a Simulink.Signal object.
ssGetDWorkRTWStorageClass	Get the storage class of a DWork vector in code generated from the associated S-function.
ssGetDWorkRTWTypeQualifier	Get the C type qualifier (e.g., const) used to declare a DWork vector in code generated from the associated S-function.
ssGetNumInputPorts	Get the number of input ports that a block has
ssGetNumOutputPorts	Get the number of output ports that a block has
ssGetPlacementGroup	Get the name of the placement group of a block.
ssRTWGenIsCodeGen	Identify any code generation that is not used by the Accelerator.
ssSetArrayLayoutForCodeGen	Specify array layout of the S-function.
ssSetDWorkRTWIdentifier	Set the identifier used to declare a DWork vector in code generated from the associated S-function.
ssSetDWorkRTWIdentifierMustResolveToSignalObject	Specify if a DWork vector resolves to a Simulink.Signal object.
ssSetDWorkRTWStorageClass	Set the storage class of a DWork vector in code generated from the associated S-function.
ssSetDWorkRTWTypeQualifier	Set the C type qualifier (e.g., const) used to declare a DWork vector in code generated from the associated S-function.
ssSetPlacementGroup	Specify the name of the placement group of a block.
ssWriteRTW2dMatParam	Write a Simulink matrix parameter to the S-function's model.rtw file.
ssWriteRTWMx2dMatParam	Write a MATLAB® matrix parameter to the S-function's model.rtw file.
ssWriteRTWMxVectParam	Write a MATLAB vector parameter to the S-function's model.rtw file.
ssWriteRTWParameters	Write tunable parameters to the S-function's model.rtw file.
ssWriteRTWParamSettings	Write settings for the S-function's parameters to the model.rtw file.
ssWriteRTWScalarParam	Write a scalar parameter to the S-function's model.rtw file.
ssWriteRTWStr	Write a character vector to the S-function's model.rtw file.
ssWriteRTWStrParam	Write a character vector parameter to the S-function's model.rtw file.
ssWriteRTWStrVectParam	Write a character vector vector parameter to the S-function's model.rtw file.
ssWriteRTWVectParam	Write a Simulink vector parameter to the S-function's model.rtw file.
ssWriteRTWWorkVect	Write the S-function's work vectors to the model.rtw file.

Miscellaneous

Macro	Description
ssCallExternalModeFcn	Invoke the external mode function for an S-function.
ssGetModelName	Get the name of an S-Function block or model containing the S-function.
ssGetParentSS	Get the parent of an S-function.
ssGetPath	Get the path of an S-function or the model containing the S-function.
ssGetRootSS	Return the root (model) SimStruct.
ssGetUserData	Access user data.
ssSetExternalModeFcn	Specify the external mode function for an S-function.
ssSetOptions	Set various simulation options.
ssSetPlacementGroup	Specify the execution order of a sink or source S-function.
ssSetUserData	Specify user data.
ssSupportsMultipleExecInstances	Allow an S-function to operate within a For Each Subsystem.