Device for implementing hierarchical state charts and methods and apparatus useful therefor

A method implementing hierarchical state charts, the method comprising:

• providing a state machine engine (SME) operative to carry out repertoires of behaviors of a system;
• replicating, in computer code form, a user-defined hierarchical state chart describing a repertoire of behaviors of said system, said replicating step being operative to preserve said state chart's hierarchical structure intact;
• generating, for each individual event from among a plurality of events within the repertoire, a list of at least one transition between states of said state chart which are associated with said individual event;
• and
• activating said system to carry out each of the behaviors in its repertoire.

An automatic code generation method comprising:

• automatically generating code which forms, in memory, a replica of a hierarchical state chart which preserves said chart's hierarchical structure;
• automatically generating code which forms, for each of a first plurality of input events, a list of transitions affected by that input event;
• automatically generating code which forms, for each of a second plurality of internal data variables, a list of transitions affected by changes in that internal data variable;
• automatically generating code which notifies the state machine engine of changes in internal data variables;
• and
• automatically generating code which evaluates conditions and implements actions and activities.

A method for computing a state for a hierarchical state machine, the method comprising:

• providing a state machine engine operative to receive notification regarding occurrence of at least one event;
• providing a hierarchical state chart describing a repertoire of behaviors of a system;
• providing a list of at least one transition between states of said state chart for each of said events with which said at least one transition is associated;
• evaluating said list of at least one transition so as to select a transition to be performed in response to said at least one event;
• and
• evaluating said hierarchical state chart to compute the state that corresponds to said selected transition.