The PC Engine was pretty popular in Japan, but only the coolest kids in America had the US edition, the TurboGrafx16. These two systems weren’t exactly the same; the TurboGrafx-16’s data bus was flipped so the games were made to be incompatible, and the US games have a region lockout. [Kaz] looked at the existing hacks for running Japanese games on US systems, and every single one of them required modding a console. Thinking he could do better, he came up with the PC-Henshin, an adapter and CPLD that allows Japanese game to run on US consoles.
To take care of the mixed up lines on the PC card connector between the US and Japanese variants, a few adapter cards are available. That’s great, but they only solve one part of the compatibility problem. The region lockout routine found on nearly every American title mean PC Engine consoles can’t run TurboGrafx-16 games. [Kaz] used a small, cheap CPLD to read the data bus, patch everything as it is read out, and turns a Japanese console into something that can play American games.