Library and use clause in VHDL - Mini Project: Build & Apply

Using Library and Use Clauses in VHDL

📖 Scenario: You are designing a simple digital circuit in VHDL. To use predefined components and packages, you need to include the correct library and use clauses at the beginning of your VHDL file.

🎯 Goal: Learn how to write library and use clauses in VHDL to access standard packages and components.

📋 What You'll Learn

Create a library clause for the IEEE library

Add a use clause to include the IEEE standard logic package

Write a simple entity and architecture using std_logic type

Print the entity name as output (simulated by a comment)

💡 Why This Matters

🌍 Real World

In real digital design projects, you must include the correct library and use clauses to access standard components and types.

💼 Career

Understanding how to include libraries and packages is essential for FPGA and ASIC design engineers working with VHDL.

1

Create the IEEE library clause

Write a library clause for the IEEE library exactly as library IEEE;

VHDL

# Your code here

Need a hint?

The library clause tells VHDL which library you want to use. For standard logic types, you need the IEEE library.

2

Add the use clause for IEEE standard logic package

Add a use clause exactly as use IEEE.STD_LOGIC_1164.ALL; below the library clause

VHDL

library IEEE;
# Your code here

Need a hint?

The use clause imports all definitions from the IEEE standard logic package so you can use std_logic types.

3

Write a simple entity and architecture using std_logic

Write an entity named SimpleCircuit with one input input_signal and one output output_signal, both of type std_logic. Then write an empty architecture named Behavior for it.

VHDL

library IEEE;
use IEEE.STD_LOGIC_1164.ALL;
# Your code here

Need a hint?

The entity defines the inputs and outputs. The architecture describes the behavior. Use std_logic type for signals.

4

Output the entity name as a comment

Add a comment line exactly as -- This is the SimpleCircuit entity at the end of the file to simulate output

VHDL

library IEEE;
use IEEE.STD_LOGIC_1164.ALL;

entity SimpleCircuit is
    Port ( input_signal : in std_logic;
           output_signal : out std_logic);
end SimpleCircuit;

architecture Behavior of SimpleCircuit is
begin

end Behavior;
# Your code here

Need a hint?

Since VHDL does not print to console, use a comment to show the entity name as output.