Analogue hasn't given a lot of detail about how they developed the Mega Sg, but to the extent that they did any reverse engineering beyond what the emulation community had already done they seem to have used similar techniques. At one point they had an identical compat bug as in my software emulator (order that bytes were updated in VRAM was swapped causing a single-frame glitch in the bike shop of one of the Road Rash games). I don't think they were using my code as a reference, but it does suggest use of similar documentation sources or similar reverse engineering techniques.

By contrast, this is the first effort (well second if you consider the nukeykt's initial C version) to try and recreate the entire system from analysis of silicon die photos. If you just want to enjoy some old games the difference is probably not particularly important, but Nuked-MD-FPGA is already passing some tests that the Mega SG does not. The screenshot in the lower right corner of the "Progress" section is a timing torture test ROM that the Mega SG fails at least 40 subtests for (I say at least because the results I've seen for Mega SG are from an earlier version of the ROM with fewer subtests).

I love what Analog does, I've got their Gameboy device on my wishlist. I can't yet warrant buying it since I don't actually own any Gameboy cartridges so it'd be roms and the like, but still.

Have you ever been in contact with them? I can imagine your and their skillsets would be very compatible with each other.

If you're okay with the moral implications (I am because the original manufacturer/publishers don't make the games available anymore so it's literally impossible to give my money to them) There are cheap flashcarts available, so you can live a better experience than you ever could with the original hardware.

I’m less interested in playing old games than having an accurate description of the hardware to study and visualize. Hopefully one day they’ll release their source so we can see where they differ with your project.

Thanks for explaining the screen grab from the torture test ROM; this is brilliant!

> Hopefully one day they’ll release their source so we can see where they differ with your project.

Just to be clear, Nuked-MD-FPGA is not my project. I'm the author of a traditional software emulator who happens to have been following development of this with keen interest. I do agree that it would be interesting to see the source of the Mega Sg though.