Thanks for your friendliness!
Actually, I was not used to visit this site. It was told me to put here my MOC! :)
As said in the discription, I took about 3/4 months building it, but pieces and ideas has come a long time before.
Programming was done during and after construction. And as you can imagine, I'm allways developing the program, solving some problems, cause it's never 100% perfect, but I'm working on it!
Coins are detected through its size and conductibility(?).
Calvin, I am a student of electronic engineering, first year ;) Everything is my work, but it's not as difficult as you can think! Just a few resistances connected to input ports to get different values when coins do the connection. Keyboard works the same way!