Difference between revisions of "Sega Mega Drive/Quirks"
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GerbilSoft (talk | contribs) (Moved to Sega Retro on request.) |
GerbilSoft (talk | contribs) (→TAS instruction support: Games that use TAS and hence break on Genesis 3) |
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* Emulators that do not implement TAS: Probably all. | * Emulators that do not implement TAS: Probably all. | ||
* Emulators that do implement TAS: '''Unknown''' | * Emulators that do implement TAS: '''Unknown''' | ||
+ | |||
+ | Games that use the TAS instruction: | ||
+ | * [[Gargoyles]] by Buena Vista Interactive | ||
+ | * [[Ex-Mutants]] by Sega | ||
[[Category:Sonic Community Hacking Guide]] | [[Category:Sonic Community Hacking Guide]] |
Revision as of 00:47, 28 December 2010
This is a list of several MD hardware quirks that don't exactly fit in any other categories.
CLR on VDP data port
If the VDP is set to VRAM/CRAM/VSRAM Write, using the clr instruction on the VDP data port will result in a system crash:
- Emulators that implement this quirk: Unknown
TAS instruction support
The MC68000 has an instruction, TAS (test-and-set), that is used for synchronizing multiple MC68000s in a multi-CPU system. The TAS instruction uses a different bus cycle than other instructions, and isn't supported by either the MD1 or MD2 hardware. However, the Majesco Genesis 3 does support TAS, which breaks a few games that incorrectly use the TAS instruction.
- Emulators that do not implement TAS: Probably all.
- Emulators that do implement TAS: Unknown
Games that use the TAS instruction:
- Gargoyles by Buena Vista Interactive
- Ex-Mutants by Sega