LX9R3-BASED USB MEGADRIVE DEVKIT You'll need an lx9/r3 board: https://github.com/makestuff/lx9/tree/r3 ...and a umdkv2-lx9/r1 board: https://github.com/makestuff/umdkv2-lx9/tree/r1 You can then follow the instructions in the Wiki: https://github.com/makestuff/umdkv2/wiki