DualJoy is USB-adapter for retro joysticks, developed by Sven Anderson. The adapter is built with a Rapsberry Pi Pico and can connect two D-Sub 9 joysticks, as they were used for example with the Atari 2600 console and the Commodore C64 and Amiga home computers. They will appear as two digital hats/d-pads with only one button.