“An easy to construct RGB cube with a fantastic light show in software.
This is one of a series of instructions on building LED cubes with the MEGA. The overall purpose is to build cubes without a lot of external hardware. They’re typically hard to build because they require lots of shift registers, numerous ICs mounted on a PC board. We are trying to keep things simple and able to be hand wired.
The first of these projects was a 5x5xx5 blue LED cube (single color). It is discussed in detail here. It was extremely easy to build, since the only external hardware to our Arduino Mega was 5 transistors and a bunch of resistors. I realized that with just 10 more transistors and 10 more digital pins, we could use the same design to build an RGB cube. That is this project. In a future project, I will build an 8x8x8 single color with very little external hardware.
This is an RGB cube. RGB cubes are built using 4 lead RGB LEDs. They are harder to build and harder to program, but with the use of a coding scheme called bit-angle modulation, we can create a whole spectrum of colors and create a variety of animations and effects not possible with a single color cube.”