The developer Apocalypse is now selling a cartridge adapter that lets you play Colecovision games on the Sega Master System. This does on-the-fly translation of the memory and port mapping with zero lag added, so think of this truly as an “adapter” and not “emulation”. The price is $70 plus shipping and it includes the adapter with SMS-style shell and standard SMS box. You can place an order by contacting Mitsurugi-w; Check out the thread below for instructions. There’s a long list of stuff you should know before buying, so check that out below the link:
Main Page: https://www.arcade-projects.com/threads/now-available-colecoco-master-adapter.29009/
I think the first thing to start with is the controller – Even though both controllers have DB9 connectors on them, you can’t just connect a Colecovision controller to a Master System – The pinouts are different and it could cause damage to the controller or console…or at best, it just won’t work the way you want it to. So, to access the numbers on the keypad via an SMS controller, hold the PAUSE button on the console, then hit the corresponding direction/button combination:
Next, this adapter is only for the Sega Master System 1 and 2. Both NTSC and PAL versions are supported, however it will not run on a Genesis / Mega Drive via a Power Base Converter, for the same reason the Genesis can’t play SG-1000 games – The VDP doesn’t support the legacy video mode, plus the Genesis in SMS mode lacks many signals on the cart slot and there’s just no way to make this work. It also will only work through the MK-2000 (Japanese SMS)’s rear expansion port via a cartridge adapter; The MK-2000 cartridge slot is also missing some of the signals available on standard Master System 1 & 2’s, so you can’t use a top-adapter and an “MK-2000 cart” version isn’t possible.
Compatibility with all original retail games is excellent, with the only issues found so far are graphical glitches with Dragon Fire on the SMS2 and Rock’nBolt has issues on both. Some newer games won’t work, but this might also be due to some using 3.3V parts on a 5v system…something we’ve been warning people about in the retro community for almost a decade now ;/ Also, none of the expansion modules (or features they support) are compatible, as those require extra pins that don’t exist on the SMS.
Even if games work, the colors will be a bit off, which is due to a flaw in the hardcoded colors of Sega’s VDP design. The same issue is present when playing SG-1000 games on a Master System via ROM Carts, or original carts on a Japanese SMS; This isn’t a result of the adapter, just how the VDP works. Some games may look better, others might look off, but overall it’s not a massive difference.
As with Apocalypse’s Game Gear to SMS cartridge adapter, there’s a bunch of tradeoffs and this product definitely isn’t for everyone. That said, I love the thought of playing the few ColecoVision games I like via the original cartridge…but with my SMS and a better controller. If you’d like to see the prototype in action, here’s a video from a few years back showing it working:
