Kega is the ONLY emulator that you can do the code on. I've tried it on Gens, Genecyst, KGen, Retro-Drive, and several others -- only Kega can pull it off. Also, I agree totally with people who say the D-Pad is helpful -- I couldn't do it on a 3 button controller, but could pull it off on a 6 button. The arcade pads are just easier to manouver, making doing the code easier. Also, I always found that to perform the code successfully, you need to have a good rhythm. Press each button with proper timing so that you hit the first "up" the moment the screen turns black, and the last "up" right before it flashes white, and have equal timing between all the button presses. I'd say aim for roughly (because I haven't tested this) somewhere between 135 and 145 BPM in your button pressing rhythm. This is for the NTSC version -- I don't know if the PAL version goes slower or not.