How to Build a Simple LED Cube 4x4x4 - Part 4

Software
The software is derived from my earlier LED cube, the charlieplexed version. Of course the "hardware layer" had to be changed, because physical control of the LEDs is different. But the rest is very similar.

How to Build a Simple LED Cube 4x4x4 - Part 3

Connecting the Electronics
There isn't much, really. First, solder the microcontroller's socket to the perfboard, then the socket of the driver. I didn't use a socket for the driver initially, which I regretted later...

Here is a schematic.

How to Build a Simple LED Cube 4x4x4 - Part 2

Building the Cube Structure

In part one we prepared all LEDs for the assembly of the cube. Now, we start in earnest...

How to Build a Simple LED Cube 4x4x4 - Part 1

Project Features

• Easy to build
• Only two active components (apart from the LEDs, of course)
• Includes detailed build instructions, schematics and software

Introduction
When I posted my charlieplexed 4x4x4 LED cube I did so in order to show an alternative implementation for such a cube. Its unique feature is that it only uses 9 controller ports. For some reason it gets a lot of interest from lots of people. And I had quite a few requests for schematics because people wanted to build it.

The problem with it is that it is only simple in terms of hardware requirements. But it is relatively complicated to understand its structure. So I thought I should try my hands on a really simple, easy to build LED cube and write a post including build instructions for people with basic skills in electronics.

The Charlie Cube Mark II: 4x4x4 - Update

Update
Build this simpler version instead!

Introduction
When I wrote my post on my charlieplexed LED cube, I never meant to publish build instructions. There are plenty of instructions around and a regular LED cube is much easier to make.

Instead, I wanted to show that it is possible to use charlieplexing for such a cube. And I wanted to share my thoughts on how I got there. So I never published schematics for the cube. Also, it is relatively difficult to draw a 3D electronic structure on a 2D schematic.

But quite a lot of people asked for a schematic. So in the end I just tried my best to draw it in an understandable way. I still think that for someone with some basic knowledge of electronics it is better to try to follow my explanations in the original post. But anyway, here it is.

The Charlie Cube Mark II: 4x4x4

Project Features

• Minimal hardware
• Wiring more complex than standard led cubes
• LED duty cycle 1/8

Update: There is a schematic and part list available here.
 
WARNING: Do not build this cube unless you know what you are doing! It uses minimal hardware but is difficult to understand.

There is a new design which is much easier to build with a very low part count.

Introduction

When I had finished my first charlieplexed LED cube (3x3x3) I wondered whether my next project should be a 4x4x4 cube. But at the time I thought it wasn't worth the effort. After all, I had just shown that a charlieplexed cube is possible and that it can be done with reasonable effort.

The 4x4x4 would of course have 64 LEDs, which would mean quite a lot of soldering. And since I would definitely want to use bright wide-angle LEDs, it wouldn't come cheap.

But the idea never really went away and when I found a good offer for a set of 100 suitable blue LEDs I simply couldn't resist.

The Charlie Cube

Project Features

• 27 LEDs in a 3x3x3 configuration
• Controller is a AVR tiny13 with 1 kByte of program memory
  
• Programmed in C

Introduction

The idea is not new. You can find loads and loads of LED cubes on the net. Some are small, some are insanely large and some even use RGB LEDs. And I must say I like them all. One LED-cube caught my eye because it mentions that it uses charlieplexing to control the LEDs. Its size is 5x4x4. But the instructable also says that with the 14 ports used it could have controlled 182 LEDs instead of the 80 it actually uses.

This got me thinking. How would you go about if you wanted to make a charlieplexed LED cube with efficient use of the available ports? Basically, with charlieplexing you get a multiplexed 2D matrix. How do you fit that into a 3D cube? (For the rest of this post I assume that you know what charlieplexing is.)