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Specify the sample time of an input port


real_T ssSetInputPortSampleTime(SimStruct *S, int_T inputPortIdx,
 real_T period)



SimStruct that represents an S-Function block.


Index of the input port whose sample time is being set.


Sample period.


The real_T value of the sample time passed into the macro.


Use in mdlInitializeSizes (after ssSetNumInputPorts) to specify the sample time period as continuous or as a discrete value for each input port. Input port index numbers start at 0 and end at the total number of input ports minus 1. For a continuous sample time, specify period as CONTINUOUS_SAMPLE_TIME. To inherit the sample time, specify period as INHERITED_SAMPLE_TIME. You should use this macro only if you have specified port-based sample times.

If the S-function specifies INHERITED_SAMPLE_TIME for any of its ports, the S-function should include an mdlSetInputPortSampleTime callback method. The callback method should set the sample time and offset of ports that inherit their sample time to the status that the Simulink® engine assigns to them using its sample time propagation rules. The callback method can also assign the sample times and offsets of other ports on the block whose sample times are inherited.


C, C++


See the S-function sfun_multirate.c used in sfcndemo_sfun_multirate.

Version History

Introduced before R2006a