Bob

‘Gear Master’ Announced: Game Gear Cartridges on SMS

Developer Apocalypse just unveiled a prototype that allows you to do what many of us thought was impossible:  Play Game Gear cartridges on a Sega Master System!  More details below, but there’s one giant problem that needs to be solved before these can be made into a production device:  We need a place to purchase, or make Game Gear cartridge slots!  While yes, you can use a Game Genie for a prototype or two, we need a permanent solution to make this product happen.  Please post in the thread below if you can help:

Arcade-projects:  https://www.arcade-projects.com/threads/introducing-the-gear-master-plays-unmodified-game-gear-games-on-master-system.17690/
SMS Power is always a good source of SMS/GG info as well:  https://www.smspower.org/

If Apocalypse can source those connectors, this would essentially be a “Super Game Boy” for the SMS…with a few caveats.  First, each console can only display up to 32 colors at a time, however the SMS has a total palette of 64, while the GG’s palette has 4096 colors.  As a result, this adapter has to drop the two least significant bits for each of the Game Gear’s color – Sometimes this will be fine, but it could potentially change the look of the game.

Next is resolution:  The SMS outputs 256×192, while the GG is 160×144.  That means like with the SGB, there will be unused space around the screen…but unlike the SGB, there’s potential for interference around the main game area.  As seen in many GG2SMS conversions, when trying to play these games on an SMS (or with emulation) you often get artifacts all around the borders.  I’m not sure if this adapter can address that in any way, but I’d certainly like to test the most popular Game Gear games and see how they look.

There’s also the Start button to consider:  Will this just be mapped to “Pause” on the SMS, or can there be a button combo to emulate it?  Or even better:  Can a Genesis controller be used instead?

Here’s the current features of the Gear Master.  I’m really excited to try this out and will have a full review that demonstrates all the above issues, if I’m able to purchase one:

  • Defeats ROM header BIOS / Region checks
  • Reduces palette by dropping the 2 least significant bits for each color (The GG has 4096 colors & the SMS only has 64)
  • Handles the start button
  • Disables writes to ports $00~07 since they are within the range of the memory and I/O control registers (unexpected writes to the memory control registers can cause to deactivate ROM or RAM access, resulting in a crash indeed)

UPDATE:  Apocalypse posted a second video:

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