Simulink is widely used within the industry for simulation and model-driven development, and reactive behaviors are often modeled using an add-on called Stateflow. Argos is one of the synchronous languages that have been proposed for the specification, validation and implementation of reactive systems. It is a rigorously defined graphical notation which, though not as powerful as Stateflow, is much less complicated. This paper describes the implementation of an Argos block for Simulink.