Duplo brick with RGB LED and microcontroller

cults3d

This is a Duplo Brick with space for various features. A 5mm LED, a CR2032 holder and a button switch are just a few of the things you can add to this brick. In my case, I used an ATTiny85 microcontroller and made the LED an RGB LED. The button has two main functions: if you press it in rhythm, the LED will repeat your favourite colour; if you long-press the button, you can select what is your favourite colour by cycling through hues until satisfied. My two-year-old loves this brick! I rewrote everything from scratch as a remix of topacsz' Smart LEGO Duplo Brick. The main differences are that it does not use a CR2032 holder and uses a panel-mount switch instead. These were the components I had available at the time, but I thought the bigger button would be easier to manipulate for a child's hand. There is still much room for improvement: the microcontroller has one free pin which can be used for a tiny speaker; the 5mm RGB LED could be replaced by a WS2812 with a smaller footprint and fewer pins. This would have made it safer for young eyes, and having a flat wall would have also made it more resilient. I housed the microcontroller in a DIP8 socket to remove and reprogram it easily, but including an ISP header on the side of the brick would have been the real "pro" solution. However, soldering all this inside the brick would have been a nightmare!