Stateflow

Transitions

You model the behavior of reactive systems by changing from one state to another through an object called a transition. This section contains the following topics on the transitions in Stateflow diagrams:

• What Is a Transition? -- Gives a description and examples of transitions and transition segments.
• Transition Label Notation -- Gives the syntax for a transition label, which can include conditions and actions. Also defines a condition and the different types of actions in a transition label.
• Valid Transitions -- Describes the situations under which transitions become valid and are taken during execution of the Stateflow diagram.

What Is a Transition?

A transition is a curved line with an arrowhead that links one graphical object to another. In most cases, a transition represents the passage of the system from one mode (state) object to another. A transition is attached to a source and a destination object. The source object is where the transition begins and the destination object is where the transition ends. This is an example of a transition from a source state, On, to a destination state, Off.

Junctions divide a transition into transition segments. In this case, a full transition consists of the segments taken from the origin to the destination state. Each segment is evaluated in the process of determining the validity of a full transition.

The following example has two segmented transitions: one from state On to state Off, and the other from state On to itself:

A default transition is a special type of transition that has no source object. See Default Transitions for a description of a default transition.

State Label Notation

Transition Label Notation