Writing S-Functions

S-Function RTWdata

There is a property of blocks called RTWdata, which can be used by the Target Language Compiler when inlining an S-function. RTWdata is a structure of strings that you can attach to a block. It is saved with the model and placed in the model.rtw file when generating code. For example, this set of MATLAB commands,

• mydata.field1 = 'information for field1';
  mydata.field2 = 'information for field2';
  set_param(gcb,'RTWdata',mydata)
  get_param(gcb,'RTWdata')
  

produces this result:

• ans = 
   
      field1: 'information for field1'
      field2: 'information for field2'
  

Inside the model.rtw file for the associated S-Function block is this information.

• Block {
    Type                    "S-Function"
    RTWdata {
      field1                  "information for field1"
      field2                  "information for field2"
    }
  

Fully Inlined S-Function with the mdlRTW Routine

The Direct-Index Lookup Table Algorithm