14
In what is perhaps the most Arduino boards used together, 130 Arduino Nanos, (plus an Arduino Mega), 130 RFID readers, and 750 RGB LEDs power this interactive crossword puzzle.
As you might suspect, bringing a giant crossword puzzle to life was lot of work. If you’d like to know how much, you can see the process laid out in the video below. Like many great hacks, this project starts out with a lot of prep, making sure the mechanical pieces go together as they should. Everything is then wired and programmed, and on day six, it finally goes out the door, destined for the National Museum in Warsaw, Poland.
Each letter has an RFID tag. Under the table are custom made circuits with Arduino Nano, RFID reader, and WS2812B. There is 130 of those circuits and the are connected by I2C interface together to Arduino Mega 2560, which is the main brain. So basically, the table recognizes letters and takes proper actions.
- When there is no letter: LED are dimmed white
- When letter is good: LED are green
- When letter is bad: LED are red
- When whole word is completed: LED play colorful animation
The main controller (Arduino Mega) communicates with a PC via RS-232. This PC plays special graphic visualization on the wall. When the whole crossword is completed, the whole table begins doing disco + sound effects.
It’s quite a colorful display, and it looks like the kids playing with it in the “Anything Goes” exhibition love it! You can see more about this project in Robert Mordzon’s write-up.
