Have you ever wondered that you can express your emotion through a rock? Ok, it might sound a little bit ridiculous, but isn’t everything possible, especially in this bizarre 21st century?
Well, some of you here might have heard this method before, but have you consider to build a magical Mood Rock?
It isn’t too hard to find the alabaster rock, where you can easily find it at the art stores.
The project is very simple. It’s fully based on the AVR-USB, it would be a cool experience to control the color from the PC with the AVR-USB microcontroller. The reason why AVR-USB is the best option, as it can easily handle the USB protocol in firmware and doesn’t need any additional ICs at all!
By the way, you should restore the bit-bang SPI, if you discovered that the SPI on the AVR were stop working. The cable is an ISP programming interface for the AVR.
In order to stick the AVR-USB microcontroller below the rock, you have to use a masonry bit to drill several holes in the bottom of the rock. Don’t forget to use a hammer and chisel to finish enlarging the space as well.