Difference between revisions of "Mega Drive Unlicensed Game Emulation Notes"
From Sega Retro
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| − | :''TODO: Is there a better category? And I have to add everything =P'' | + | :''TODO: Is there a better category? And I have to add everything =P (plus ROM addresses, SRAM specifics, etc.)'' |
Unlike official Mega Drive games, unlicensed games usually have copy protection schemes, SRAM mapping oddities, or other hardware quirks that emulator authors should take note of if they want their emulators to work with these games. sha1sums of dumps to watch out for are given. | Unlike official Mega Drive games, unlicensed games usually have copy protection schemes, SRAM mapping oddities, or other hardware quirks that emulator authors should take note of if they want their emulators to work with these games. sha1sums of dumps to watch out for are given. | ||
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*[[Zhong Guó Xiàng Qí]]: presently undumped | *[[Zhong Guó Xiàng Qí]]: presently undumped | ||
[http://pastebin.com/gnPbJdRS All Realtec games use a custom mapper format documented by TascoDLX.] | [http://pastebin.com/gnPbJdRS All Realtec games use a custom mapper format documented by TascoDLX.] | ||
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| + | ==[[Tiny Toon Adventures 3]]== | ||
| + | Affected ROMs: | ||
| + | *''TODO'' | ||
| + | The game writes a value (TODO) to $400000 (this address is somewhat obfuscated in ROM) and expects to read it back from $400002 (TODO verify); otherwise, the game will reset itself. | ||
==[[Ya Se Chuan Shuo]]== | ==[[Ya Se Chuan Shuo]]== | ||
Revision as of 00:48, 28 July 2011
- TODO: Is there a better category? And I have to add everything =P (plus ROM addresses, SRAM specifics, etc.)
Unlike official Mega Drive games, unlicensed games usually have copy protection schemes, SRAM mapping oddities, or other hardware quirks that emulator authors should take note of if they want their emulators to work with these games. sha1sums of dumps to watch out for are given.
All Realtec Games
- TODO: wikify this
Affected ROMs:
- Whac-a-Critter: 4b45801b112a641fee936e41a31728ee7aa2f834
- Funny World & Balloon Boy: 17481c8327433bfce8f7bae493fc044194e400a4
- Earth Defense: 9bf4cda850495d7811df578592289018862df575
- Zhong Guó Xiàng Qí: presently undumped
All Realtec games use a custom mapper format documented by TascoDLX.
Tiny Toon Adventures 3
Affected ROMs:
- TODO
The game writes a value (TODO) to $400000 (this address is somewhat obfuscated in ROM) and expects to read it back from $400002 (TODO verify); otherwise, the game will reset itself.
Ya Se Chuan Shuo
Affected ROMs:
- "Imperial Dynasty" version: presently undumped
- "The Legend of Arthur" version: 8fe0806427e123717ba20478ab1410c25fa942e6
The Data East/Side Pocket driver stolen from High Seas Havoc used in this game is slightly modified; an add from Z80 RAM to a register (TODO) is used. If this instruction is not emulated correctly, the play song routine will load invalid music and eventually crash.
Furthermore, the Z80 sound driver presumably expects that the uppermost 32KB of ROM (from $1F8000) be mirrored at $400000. This needs to be confirmed.