Magic Cards With Arduino


Introduction: Magic Cards With Arduino

About: I'm a Mechanical Engineer and an enthusiastic Maker. I like to create and code my projects using the Arduino.

Hello, everyone!!

The Magic Cards is my unique creation that can read your mind and can find out what was your choose on a display with 64 numbers, letters, symbols or whatever else you want.

You can create many different personal templates to be used with Magic Cards.

But how Magic Cards does work?

It asks a few questions (6 in total) that you just need answer YES or NO according to LED array connected.

If you see the number you chose in ON LED group, your answer is YES (Green tactile switch).

If your number is not highlighted, your answer will be NO (Red tactile switch).

With just these clues, after six questions, the Magic Cards can figure out what it was like by showing it on a flashing screen.

You can repeat (pressing Green/YES tactile button) for any other number of your choice and Magic Cards will give you the correct answer all the time.

And what makes Magic Cards special and unique is that you can repeat the same number you choose before and you will see that Y/N responses will be different, but the end result will always be right!

I have created the logic of this code a long time ago and I have improved over time on different plataforms during development in versions for Excel-VBA, Visual Basic, C++, Lazzarus (Delphi) and Arduino was an extension of all these versions.

I also have a version with printed cards and someday I will introduce them to everyone on a future project. Well, let's have fun now!! It is very simple to be built and very interesting!!


Step 1: Material & Assembly

• Material

- 01 Arduino Uno or similar

- 01 LED Display 8x8 (module with MAX7219)

- 01 mini-breadboard

- 02 push-buttons

- 01 printed template for LED display

- Jumpers

• Assembly

- Follow the ilustrated diagram

- Print the template, cut and put it over the LED Matrix

- Upload the Arduino program

• Libraries for Arduino

- Library to control the LED Matrix with MAX72xx

- Library for Timer1 to read the push-buttons.

Step 2: Operation

• Operation

After start you need to answer 6 questions about the number you have imagined.

If you see the number you have chosen on the display, press the buttom Green (Yes, it is shown in the display) or Red ( No, my chosen number is not shown in the display).

Answer correctly all the 6 questions and at end you will see your chosen number blinking on the display !!

At the end. any button you press will restart the game.

Best regards,



Last update in: 10.Feb.2016



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    Doesn't work for me, I tried with Arduino Uno and Nano (100x checked wiring) but the result number is always wrong ?!!! Any clue ?

    2 replies

    Hello, Ludovic,

    I repeated the same procedure I told you in my another publishion site and the code is working correctly. The difference between this code of Instructable and the another code is related to library to read the tactile keys and also the presentation of results. Here you see the answer number blinking on display. In my another version (newest) only the LED of the number of answer is blinking because you can use in this case another paper patterns for the display.

    Again, both versions are working correctly. Please, take care with the wiring connections.