Writing S-Functions

Level 1 Versus Level 2 S-Functions

The original S-function interface was called the Level 1 API. As the capabilities of Simulink grew, the S-function API was rearchitected into the more extensible Level 2 API. This allows S-functions to have all the capabilities of a full Simulink model (except automatic algebraic loop identification and solving) and to grow as Simulink grows.

Creating Fortran S-Functions

Creating Level 1 Fortran S-Functions