You just want to play an old game in an emulator. Or you have just built a MiSTer FPGA. Surely you have various joysticks for the good old home computers, such as Atari or Commodore, at home, but they all have in common that there is a 9-pin connector for connection to the computer. PCs never had such a connector. Today, USB is almost always used as the interface. How you can build such an adapter on a breadboard in a very simple way, I would like to describe you in this article.