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Author Topic: Sega MegaPlay  (Read 1553 times)

FireRat

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Sega MegaPlay
« on: November 20, 2016, 03:24:23 pm »
Hello. I'm a 68000 Assembly game programmer with a very minimal knowledge on C and nothing on C++ I guess...
I work on romhacks and homebrew software for the Sega Genesis and CD, and I'd like to try something on the Sega Megaplay, which in essence is a Sega Genesis with extra hardware to handle the game's how-to instructions and coin support.

To achieve this goal, I'm willing to reverse engineer a MegaPlay game, whose code for its original version I have mostly memorized thanks to an already existant disassembly. This game is Sonic The Hedgehog 1, but I could try the simpler-looking Sonic 2 MP ROM.

I can use IDA Pro to disassemble the 68k ROMs and base my project upon the MP-specific code (to keep it "compatible" if I ever get luck to have this game on the real hardware), however, it is hard to determine what is the code exactly doing without even knowing how the extra hardware looks like on the new address map.

So my question is: Do anyone have any useful information about this platform? Any notes would be greatly appreciated!!!

According to MAME, this is the main processing file: https://github.com/mamedev/mame/blob/master/src/mame/drivers/megaplay.cpp.
If anyone can understand how the address map would look like, that would be greatly appreciated as well.