This project is designed to fade between seven different colors using an RGB LED. To keep things simple, Flakko decided to avoid PWM using a microcontroller. He used a binary counter to cycle through the color sequence. To do the fading between colors he added an RC filter. It’s a pretty simple device and the parts are more common than the ones in the Bit-tech article he referenced. YouTube video of the fader.
[thanks Javier Flores]