Chapter 7 Configurations

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, pro-

vides 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 archi-

tecture that has different port names from the architec-

ture 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.

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