FPGA Practical Labs

Hands-on FPGA laboratory
From blink LED to RISC-V softcore — learn FPGA by doing!

Documentation · Hardware

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What is an FPGA?

An FPGA (Field-Programmable Gate Array) is a semiconductor device that can be reprogrammed to implement various digital circuits and functions. Unlike ASICs, FPGAs offer flexibility and adaptability, allowing designers to modify functionality even after manufacturing.

FPGA Architecture Overview

An FPGA consists of three fundamental building blocks:

1. Configurable Logic Blocks (CLBs) - The basic computational units
2. Interconnect Architecture - Programmable routing between blocks
3. Input/Output Blocks - Interfaces to external devices

Configurable Logic Block (CLB) Structure

Each CLB contains:

• LUT (Look-Up Table) - Implements combinational logic functions
• Flip-Flop - Stores state for sequential logic
• Multiplexer - Selects between combinational or registered output

The CLB provides the basic logic and storage functionality, executes complex logic functions, and synchronizes operations using flip-flops with a clock signal.

Gate-Level Implementation

Figure: Detailed gate-level view of CLB components

The diagram above shows how each CLB component works at the logic gate and mathematical level:

1. LUT (Look-Up Table)

• Mathematically: A LUT with n inputs implements any Boolean function of n variables
• A 2-input LUT is a 4×1 memory: Output = Memory[2×A + B]
• Gate equivalent: Can implement AND, OR, XOR, or any truth table

2. D Flip-Flop

• Mathematical model: Q(t+1) = D(t) when clock rises (▲)
• Stores 1 bit of state synchronously
• Output only changes on the rising edge of CLK

3. 2:1 Multiplexer

• Boolean equation: Out = (¬Select · LUT_Out) + (Select · FF_Out)
• Selects between: S=0 (combinational path) or S=1 (registered path)

4. Complete CLB

• Unified equation: CLB_Out = Config ? FF(LUT(Inputs), CLK) : LUT(Inputs)

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Documentation

Start here if you are new to FPGAs:

1. What is FPGA? - Fundamental concepts
2. Basic Verilog - Syntax and structure
3. FPGA vs Microcontroller - Understand the differences
4. Gowin IDE Installation - Set up your environment

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Getting Started

# 1. Clone the repository
git clone https://github.com/yourusername/fpga-practical-labs.git
cd fpga-practical-labs

# 2. Install tools (see docs/)

# 3. Check available projects
cd projects/

# 4. Start with Toggle LED
cd Toggle_led/

Projects

Project	Description	Status
Toggle LED	Basic LED toggle using Tang Nano 9K	✅ Available
Servo Control	Servo motor control with progress LEDs	✅ Available

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License

This project is licensed under:

• Code: MIT License 2026 FPGA Practical Labs Contributors
• Documentation: CC BY-SA 4.0

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Support

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