Update: More details in my new article.
An anonymous coder dropped off a modified SD2SNES firmware in a few places today which adds a Super Game Boy core to the SD2SNES. The Super Game Boy was a cartridge that allowed you to play Game Boy games on a Super Nintendo. It contained an entire Game Boy system inside the cart, minus the screen, and that is precisely what this new FPGA cores does for the SD2SNES.
You can now load Game Boy ROMs and “Black Cart” Game Boy Color Games (GB games w/GBC palettes, but not true GBC games, molded in black plastic) on a Super Nintendo, using any SD2SNES from the original day-one model through to the SD2SNES Pro and current FXPAK PRO. The new core boots the Super Game Boy 2 BIOS, which was a Japanese-exclusive timing-corrected hardware update to the Super Game Boy that played GB at its correct speed.
Due to the limitations of the SNES cartridge bus, only GB and black-label GBC ROMs work. True GBC games will not work. I showed off the new functionality in the video above, and I prepared a care package with all of the required files, which you can find in the video’s comments. MSU-1 audio will be possible as well, but not MSU-1 video or data hacks.
Update: to clear up some confusion
– MSU-1 Audio will be possible on both Classic and Pro
– Pro does NOT offer any additional functionality for MSU-1 video/data, it’s not physically possible. This is a limitation of the cartridge bus
– There is no difference between SGB features on SD2SNES Classic or Pro
– Again, true GBC is not supported by SGB, but there are 625 GB/GBC games with SGB Enhanced features that I’ve identified in my research for the EverDrive Pack Lists, where I have a complete collection of all SGB Enhanced games in one folder. I also have folder for GBC “Black Carts” as well as all GB games with GBC palettes.
Thanks to Qwertymodo & Beer Monkey for the technical information