This SEGA SNAC setup guide is only suitable for the Digital IO board v1.2 and the Analog IO board v6.1 and newer. All older versions of the MiSTer IO board require a hardware modification to the IO board to support SEGA controllers with the USB SNAC adapters. The required physical hardware modification is outside the focus of this quick setup guide. The two pin jumper on the USB SNAC board should be closed using the black jumper cap as shown in the first picture below. On either version of the analog v6.1 or digital v1.2 IO board locate the three jumper pins labelled IO6 and move the jumper cap to middle pin and the I/O pin as shown in the second picture. Load the MiSTer Genesis core and under the Input menu change the Serial option to SNAC, now test the controller. If the controller still does not work, pull up the core menu again and under Input change the Swap Joysticks option to Yes. The SEGA controller should now be functioning correctly with the current running game.