blastem VS moa

The libretro core seems to be outdated according to the GitHub page. It says last commit being on Jul 26, 2022. Meanwhile the standalone is Feb 20th, 2023.

BlastEm is my first reasonably complete emulator, but I had a couple of other emulation projects that didn't really go anywhere previously so you can kind of consider it the second. It took me about two months before I got things sort of working and about 11 months before my first release. It took considerably longer for things to get into reasonably good shape.

You want to use a modern and accurate emulator like BlastEm

Blastem is still under development.

Special thanks to ComradeOj for the demo ROMs, and Mike Pavone and the other contributors for BlastEm (github mirror). Without these, it would have taken a lot more time to get this working.

Dude, Kega has almost 10 years dead, use BlastEm for Roms games and Genesis Plus GX for SegaCD games.

This is the libretro fork, which is out of date with upstream, because of course it is, that's how libretro works: https://github.com/libretro/blastem

The code is here if you're interested: https://github.com/transistorfet/moa System is the top level component and devices.rs has the traits that System uses to interact with the components. The machines directory has the system definitions that build a specific machine to emulate.

A few months ago, I wrote a 68000 emulator in Rust named Moa. My original goal was to emulate a simple computer I had previously built. After only a few weeks, I had that software up and running in the emulator, and my attention turned to what other platforms with 68000s I could try emulating. My thoughts quickly turned to the Sega Genesis and without thinking about it too much, I dove right in. What started as an unserious half-thought of "wouldn't that be cool" turned into a few months of fighting documentation, game programming hacks, and my sanity with some side quests along the way, all in the name of finding and squashing bugs in the 68k emulator I had already written.

There's not much to it. Only one window can be created at the moment, and input is not yet supported. The threaded option is also not shown here. Before long, the code grew more complicated, and now includes parsing of command line arguments with the clap crate. To see the latest version, check out the Genesis machine-specific binary and the MiniFB host impl and main loop

Since the 68000 has a reasonably orthogonal instruction set, we can break down the opcode word into sub-components, and build up instructions by separately interpreting those sub-components, rather than having a match arm for each of the 65536 combinations. There is a really helpful chart by GoldenCrystal which shows the full breakdown of opcodes for the 68000. We can look at the first 4 bits of the instruction word to separate it into 16 broad categories of instruction, and then further break it down from there. The full code can be seen here