A million years ago when the megaplay roms were being dumped sonic hackers do what they do and started hacking the sonic roms. I recall them modifying the megaplay rom so it was loadable as a general Genesis rom. I have not been able to locate this hack. I do recall the pieces of the roms from the megaplay were byteswapped. I want to try to run megaplay games on a stock genesis. I've been messing with all kinds of stuff on hardware
If this is anything to go by, every other byte is part of a separate file, resulting in two 256KB files. Putting these together produces something that looks like a ROM, but Regen doesn't seem to want to run it. I'm running it through IDA now. (I had no idea this was a thing. I am gonna have some fun with this!) EDIT: Alright, check this out: I made a small C tool to put the files back together, commented out a new bsr.w just above MainGameLoop, changed the initial screenmode from 0 to 4, and got this. Fun fact, ErrorTrap had its 'nop's removed, but that's not the least of it: even without controls, the demo alone shows of some very notable changes. EDIT2: PauseGame has an rts jammed in the front of it. This would be a lot more interesting if I could control the game...
I found the roms, it was LOst's work. http://forums.sonicretro.org/index.php?showtopic=4497 If you can figure this out would you convert the remaining megaplay games over? They've never been documented on hardware, only emulators
