This is just a slight change to the SNES/NES code to allow for 4 ports (2 NES / 2 SNES)
See the README files in the subfolders for build instructions. All the adapters are build around the Arduino Pro Micro.
You will need the Arduino IDE to build the projects. Download the whole repository via the "Clone or download" button, open the project you want to build in the IDE and select "Arduino Leonardo" in Tools / Board. Connect the Arduino to a USB port and build/upload from Scetch / Upload.
This project is licensed under the GNU General Public License v3.0.
All Credit to Mick for his amazing Daemonbite source : https://github.com/MickGyver