Configurations are a primary design unit used to bind component instances to entities. For structural models, configurations can be thought of as the parts list for the model. For component instances, the configuration specifies from many architectures for an entity which architecture to use for a specific instance. When the configuration for an entity-architecture combination is compiled into the library, a simulatable object is created.

Configurations can also be used to specify generic values for components instantiated in the architecture configured by the configuration. This mechanism, for example, provides a late-binding capability for delay values. Delay values calculated from a physical layout tool, such as a printed circuit board design system or a gate array layout system, can be inserted in a configuration to provide a simulation model with actual delays in the design.

If the designer wants to use a component in an architecture that has different port names from the architecture component declaration, the new component can have its ports mapped to the appropriate signals. With this functionality, libraries of components can be mixed and matched easily.

The configuration can also be used to provide a very fast substitution capability. Multiple architectures can exist for a single entity. One architecture might be a behavioral model for the entity, while another architecture might be a structural model for the entity. The architecture used in the containing model can be selected by specifying which architecture to use in the configuration, and recompiling only the configuration. After compilation, the simulatable model...