An adapter to interface a NES Mini Controller (an I2C device) with a PC as a generic USB Gamepad; based on an attiny85.
The microcontroller uses the v-usb library to create a low-speed usb device (the gamepad) and implements some homemade code in order to process the I2C signals from the controller.
A SNES Mini Controller can probably be used with some minor code tweaks (more buttons and probably some I2C transactions adjustments), but not tested yet.