Sega Genesis/Master System to USB Converter

With my Sega Genesis arcade stick, and a more recent Master System/C64 stick I put together, I have been increasingly unhappy with commercial Genesis to USB converters. The one I have essentially assumes a 6-button Genesis Pad, and doesn't do proper detection. This means nuisance extra button presses when using a less capable device, which is no good. So I decided to make my own.

Genesis to USB converter interior Genesis to USB converter exterior

For this project, I decided on the Teensy 2.0, which gives me a small size, good IO complement, nice USB features, and most importantly: 5 volt logic.

Mechanical design was pretty basic: just a small project box, a DE9 connector, wiring to the Teensy and some drilling/dremelling. The Teensy, however, seems to be designed to mount directly by pins into a protoboard/breadboard. Since I was wiring directly to the board, I needed a different solution. Thankfully, I already had some Scotch Brand mounting tape, which works extremely well for securing small PCBs into a project.

When assembled and programmed, the converter works the way a converter of this type should work. If a 1-button C64/Atari stick is inserted, that button registers as the primary button 1 only. If a 2-button Master System stick is inserted, those two buttons become buttons 1 and 2. For the 3-button Genesis pad, the buttons are 1, 2, 3 and 10, which is a customary position for the start button on Windows games. The 6-button pad therefore adds buttons 4, 5, 6 and 9 to fill out the set. Buttons 7 and 8 positions are unused; most software would expect those to be L2/R2 buttons which have no equivalent.

For source code and more information on the software, check out the github project page. Per the project page readme, I am intentionally maintaining several branches depending on the desired USB device type. Please see the readme for more information and select the branch of interest.

Comments

There are no comments yet.

Add a Comment
Comment Atom Feed