MATLAB: What functionality is afforded by ssSetModel​ReferenceS​ampleTimeD​efaultInhe​ritance and ssSetModel​ReferenceS​ampleTimeD​isallowInh​eritance in C MEX S-functions in Simulink

Question

Some C MEX S-functions provided with Simulink use the ssSetModelReferenceSampleTimeDefaultInheritance and ssSetModelReferenceSampleTimeDisallowInheritance macros in their SampleTime routines. I would like further documentation on the functionality afforded by these macros.

Answer 1

This bug has been fixed in Release 2007b (R2007b). For previous product releases, read below for any possible workarounds:

Documentation on the ssSetModelReferenceSampleTimeDefaultInheritance and ssSetModelReferenceSampleTimeDisallowInheritance macros is missing from Simulink documentation.

Here is additional information on these macros:

The ssSetModelReferenceSampleTimeDefaultInheritance and ssSetModelReferenceSampleTimeDisallowInheritance macros are alternatives to the ssSetModelReferenceSampleTimeInheritanceRule macro. The following expressions are equivalent:

 ssSetModelReferenceSampleTimeDefaultInheritance(S);
 ssSetModelReferenceSampleTimeInheritanceRule(S, USE_DEFAULT_FOR_DISCRETE_INHERITANCE);

Likewise, the following expressions are also equivalent:

 ssSetModelReferenceSampleTimeDisallowInheritance(S);
 ssSetModelReferenceSampleTimeInheritanceRule(S, DISALLOW_SAMPLE_TIME_INHERITANCE);