Stateflow

Anatomy of a Model and Machine

The Simulink Model and Stateflow Machine

The Stateflow machine is the collection of Stateflow blocks in a Simulink model. The Simulink model and Stateflow machine work seamlessly together. Running a simulation automatically executes both the Simulink and Stateflow portions of the model.

A Simulink model can consist of combinations of Simulink blocks, toolbox blocks, and Stateflow blocks (Stateflow diagrams). In Stateflow, the chart (Stateflow diagram) consists of a set of graphical (states, transitions, connective junctions, and history junctions) and nongraphical (event, data, and target) objects.

There is a one-to-one correspondence between the Simulink model and the Stateflow machine. Each Stateflow block in the Simulink model is represented in Stateflow by a single chart (Stateflow diagram). Each Stateflow machine has its own object hierarchy. The Stateflow machine is the highest level in the Stateflow hierarchy. The object hierarchy beneath the Stateflow machine consists of combinations of the graphical and nongraphical objects. The data dictionary is the repository for all Stateflow objects.

Stateflow scoping rules dictate where the types of nongraphical objects can exist in the hierarchy. For example, data and events can be parented by the machine, the chart (Stateflow diagram), or by a state. Targets can only be parented by the machine. Once a parent is chosen, that object is known in the hierarchy from the parent downwards (including the parent's offspring). For example, a data object parented by the machine is accessible by that machine, by any charts within that machine, and by any states within that machine. The hierarchy of the graphical objects is easily and automatically handled for you by the graphics editor. You manage the hierarchy of nongraphical objects through the Explorer or the graphics editor Add menu.

How Stateflow Works

Defining Stateflow Interfaces