It being almost Christmas I decided to decorate the family tree with some RGB LEDs but I wanted a bit more fun for myself and my two-year old daughter. So I used addressable RGB LED strip driven with a DipCortex. Which lets us set any LED on the strip to any colour.
To provide some interactivity I added a set of Red,Green and Blue arcade buttons. I set them up so my daughter can walk up to the tree and set off a colour, or mix of colours, spinning up the tree. Which as well as entertaining has been fun watching her mix the colours and shout out their names.
Normally controlling a large number of LEDs requires a number of LED driver chips and lots of control lines, The strips I am using on the tree have 360 LEDs and this is all controlled via one port pin. The LEDs themselves are also very tightly packed on to the strip and this is possible because the LED driver has been embedded in to the silicon of the LED. So you end up with a small four pin device that uses two pins for power, one for communication in and the last for communication out.