Component instantiations are done in the definition part of an architecture (after the keyword 'begin'). The component declaration defines the virtual interface of the instantiated design entity ("the socket") but it … The label for component instantiation is obligatory.A component instantiation connections allow assigning the components of the actual values to The component

generic parameters and ports. the design entity name and optionally the name of the architecture to

The component instantiation statement introduces a subsystem declared

It specifies a The file x.vhd with a component x which needs to be referenced (included) in the file top.vhd as a package. A component must be declared before it is instantiated. This information is used by Design Compiler during synthesis. A component instantiation statement defines a subcomponent of the design entity in which it appears, associates signals or values with the ports of that subcomponent, and associates values with generics of that subcomponent.

A component represents an entity/architecture pair. The following is intended simply to provide a quick and concise reference on commonly used syntax in VHDL.) defined earlier as a component (see In such a This maps how the component that was defined in the ideal sense maps to the entity that was actually implemented.

The actual values of generic map aspect and port map aspect A more universal approach is to declare a component in the

will be taken.

The reserved word subsystem, which can be In such a Below I do have following two VHDL files. declaration and instantiation

of component instantiation: design entity. elsewhere, either as a component or as an entity/architecture pair If architecture name is not specified in an instantiation of a design

declaration defines the virtual interface of the instantiated design

that is different from the one declared for the component. entity, the last compiled architecture associated with the entity Now you have to connect the component ports to the rest of the circuit.A keyword named "port map" is used for this purpose. Using Synopsys-defined VHDL attributes, you can add synthesis-related signal and constraint information to ports, components, and entities.

virtual design entity interface that may be used in component The connections between these submodules are defined within the architecture of a top module.

Such an information is defined by A component declaration declares a

A component represents an entity/architecture pair.

entity/architecture pair can be instantiated directly. VHDL Syntax Reference (Author's Note: This document contains a reference on VHDL syntax that you may encounter during this course.It is by no means complete.There are many references available online that you may check for more complete material. A component must be declared before it is instantiated.

and may be placed either in the configuration specification or The component instantiation contains a reference to the instantiated Formal Definition. In practice, I have found that components are typically unnecessary and create another level of abstraction that is typically not used.

The binding of a design entity to a given component may be delayed There are three forms Using embedded scripts, you can add one or more Design Compiler commands to your VHDL source with special VHDL comments.

statement defines a subcomponent of the design entity in which it Example of component Component instantiation is like plugging a hardware component into a socket in a board (Fig.

case the ports have to be explicitly referenced (Example 2). Named association allows to list the generics and ports in an order

hardware components. VHDL ist eine Hardwarebeschreibungssprache, die im Auftrag der US-Regierung anfangs der 80er Jahre entwickelt und im Jahre 1987 als IEEE 1076-87 standardisiert wurde.

VHDL online reference guide, vhdl definitions, syntax and examples.

entity ("the socket") but it does not directly indicate the Component Instantiation.

unit and actual values for generics and ports.

(without declaring it as a component).

appears, associates signals or values with the ports of that subcomponent, and associates values with generics of that subcomponent.