Projects Overview

LED Cubes
The Charlie Cube
A 3x3x3 cube using only 6 I/O ports
The Charlie Cube Mark II: 4x4x4 
A proof of concept showing that a 4x4x4 LED cube can be controlled with only 9 I/O ports 
The Charlie Cube Mark II: 4x4x4 - Update 
Some additional information for those who want to build this cube  
How to Build a Simple LED Cube 4x4x4 
(Part 1 / Part 2 / Part 3 / Part 4)
Very detailed build instructions for a low-cost, easy to build 4x4x4 LED cube

Persistence of Vision (POV) Toys

The Micro POV 
A small and simple POV toy based on the ATtiny24
The Nano POV 
And an even smaller device based on the ATtiny25

Other LED projects

Musings on Charlieplexing
A charlieplexed 4x5 LED matrix to demonstrate the advantages of charlieplexing
A Simple Electronics Project for Kids 
A very simple and cheap torch light
Another simple electronics project for kids
A rainbow LED pendant

The Morse Thermometer 
(Part 1 / Part 2)
A thermometer powered by a solar garden lamp
A Charlieplexed Knight Rider Light
Using 4 ports of an ATtiny25  to drive 12 LEDs and one port to read a pot

LED Photos 
A few fun photos using light painting
Low-Cost High-Speed Photography 
(Part 1 / Part 2 / Part 3)
A versatile flash circuit, controlled via computer and using a high power LED


A MythTV Remote Control without LIRC
Emulates a USB keyboard, no driver needed.

A PC Watchdog
Resets a Linux server when it freezes


A USB/ISP Programmer (Part 1) 
Review of two ultra cheap Chinese ISP programmers for ATMEL chips
A USB/ISP Programmer (Part 2) 
Some extra information on available firmwares

A beginner's Guide to Driving LEDs
Part 1: LED Characteristics
Part 2: LEDs with Serial Resistors
Part 3: Current Stabilisation
Part 4: The Transistor - Zener Diode Current Source 
Part 5: LEDs with Microcontrollers

How to Do ISP Programming
The Theory (this post) 
Hardware Considerations
Software Usage
Writing Fuses / Troubleshooting
Connecting an ISP Programmer to an ATMega8


  1. which type of transistor you used ?

    1. Sorry, but I am not sure which project you are asking about.

  2. beast really liked your tutorial over not only shows the scheme to make the ligament between ATTINY24 and transistors and resistors to do to make this interconnection between those components??

  3. I wonder what the mounting of components and transistors which you used the project The Charlie Cube Mark II: 4x4x4
    ?? if you can help me I will be very grateful

    1. Hugo, please consider to build the other project "The simple LED cube". There are very detailed building instructions, it is easier to understand and the controller has much more space for additional sequences.

  4. tom i need ur help want to build a line follower robot using arduino i have one but want to build a better responsive robot with good speed

    1. Sorry I am not good either with either Arduinos or with robots. You might want to try some robot forum.

  5. How i can get 444LED cube with PIC microcontroller. i want to build this project.u can explain how to build. i want diagram because i cannot see below the email is hope u can help me.plz

    1. I don't work with PICs so unfortunately I can't help you. But I am sure that some googling will help you find similar projects based on PICs.

  6. Hi Tom I love this project! But I was wondering where the blue wires and the green wires and the pot and everything is all connected on the back? If you could answer back and maybe post pictures to show.. Thanks! Great work!

    1. This comment has been removed by the author.

    2. I'm talking about the charlieplexed Knight Rider light.

  7. This comment has been removed by the author.