Joystick switcher C64

You may have happened to have the joystick in port 2 and load a game that requires the joystick on port 1 (or vice versa).
To avoid having to unplug and reattach the connector on the correct port there is new hardware to be inserted between the Commodore ports and the joystick so you can easily swap ports by pressing just a button. 

There are different types on the market, this is a self-built and you can find the diagrams on the network, the operation is simple, by pressing the button the digital and analog signals coming from the joystick, mouse, pen or paddle are exchanged, by pressing the button again. everything will return to normal mode. The led on the button indicates whether it is in normal or inverted mode.