The Create STD File property, in the FSM Properties window, associated with MLDesigner FSM models, allows you to revert FSM models to the old format.
The main purpose for the Create STD File property is the further support of FSM code-generating tools which are based on the semantic of Ptolemy and previous versions of MLDesigner.
If the value of this property is set to Yes, the STD file with the name of the source FSM model and the extension .std is generated each time the associated FSM model is saved.
Only the top-level states of the FSM model and transitions, where the source state and the target state is a top-level state, are considered. If the FSM model contains hierarchical states a warning message occurs while generating the STD file. History states are ignored by the STD file generator. Not all the state and transition properties of the new MLDesigner FSM model can be mapped into the STD representation. The State Entry Action, State Exit Action and Transition Guard Condition property are not supported.
The action property of a transition in the STD representation simply contains a list of names of output ports of the FSM model. The transition outputs an event on these ports if the transition fires. The STD file generator parses the contents of the Action property of an MLDesigner FSM transition for the names of the FSM model output ports, to create the action for the associated transition in the STD representation.
A generated STD file is shown in the MLDesigner model file view as a submodel of the associated FSM model but it is physically stored in the same directory. Changes made to STD files do not influence the source MLDesigner FSM model and may be edited using the FSM STD editor.