To connect an old joystick, like the Competition Pro, to a modern PC, you need an adapter. This is because the old joysticks from home computers have an interface that today’s computers no longer have. On the internet you can find many suggestions. I would like to present a very interesting adapter today.
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.