Set the Output Port Data Type

You may want to set the data type of various ports, run-time parameters, or DWorks in your S-function.

For example, suppose you want to set the output port data type of your S-function. To do this,

1. Register a data type by using one of the functions listed in the table Data Type Registration Functions. A data type ID is returned.

   Alternately, you can use one of the predefined data type IDs of the Simulink^® built-in data types.

2. Use ssSetOutputPortDataType with the data type ID from Step 1 to set the output port to the desired data type.

In the example below from lines 354 - 370 of sfun_user_fxp_const.c, ssRegisterDataTypeFxpBinaryPoint is used to register the data type. ssSetOutputPortDataType then sets the output data type either to the given data type ID, or to be dynamically typed:

/* Register data type
   */
if ( notSizesOnlyCall )
  {
 DTypeId DataTypeId = ssRegisterDataTypeFxpBinaryPoint(
            S,
V_ISSIGNED,
V_WORDLENGTH,
V_FRACTIONLENGTH,
1 /* true means obey data type override setting for
this subsystem */ );

ssSetOutputPortDataType( S, 0, DataTypeId );
   }
  else
  {
ssSetOutputPortDataType( S, 0, DYNAMICALLY_TYPED );
}