What is VHDL - Hands-On Activity

What is VHDL

📖 Scenario: Imagine you want to design a simple digital circuit like a light switch that turns on a lamp. VHDL helps you describe how this circuit works using code instead of just drawing it.

🎯 Goal: You will learn what VHDL is and create a very simple VHDL code snippet that represents a basic digital circuit.

📋 What You'll Learn

Understand that VHDL is a language to describe digital circuits

Create a simple VHDL entity and architecture

Write code that represents a basic logic operation

💡 Why This Matters

🌍 Real World

VHDL is used by engineers to design and test digital circuits before building physical hardware.

💼 Career

Knowing VHDL is important for jobs in electronics design, FPGA programming, and hardware engineering.

1

Create a VHDL entity

Write a VHDL entity named LightSwitch with one input port called Switch of type std_logic and one output port called Lamp of type std_logic.

VHDL

-- Your code here

Need a hint?

Think of the entity as the 'box' that holds your circuit's inputs and outputs.

2

Add architecture to describe behavior

Write an architecture named Behavior for the LightSwitch entity. Inside it, declare that Lamp is assigned the value of Switch.

VHDL

entity LightSwitch is
    port(
        Switch : in std_logic;
        Lamp : out std_logic
    );
end LightSwitch;

-- Your code here

Need a hint?

The architecture tells how the circuit works inside the entity box.

3

Explain what VHDL does

Add a comment at the top of your code explaining that VHDL is a language used to describe digital circuits and their behavior.

VHDL

-- Your comment here
entity LightSwitch is
    port(
        Switch : in std_logic;
        Lamp : out std_logic
    );
end LightSwitch;

architecture Behavior of LightSwitch is
begin
    Lamp <= Switch;
end Behavior;

Need a hint?

Use -- to write a comment in VHDL.

4

Display the VHDL code

Print the entire VHDL code stored in a variable called vhdl_code.

VHDL

vhdl_code = '''
-- VHDL is a language to describe digital circuits and how they behave
entity LightSwitch is
    port(
        Switch : in std_logic;
        Lamp : out std_logic
    );
end LightSwitch;

architecture Behavior of LightSwitch is
begin
    Lamp <= Switch;
end Behavior;
'''

# Your code here

Need a hint?

Use print(vhdl_code) to show the code.