Would it be possible to emulate NeoGeo AES on 68k Amiga

[Karlos]

CU_AMiGA wrote:
Hi

Was wondering whether it would be possible to emulate NeoGeo AES through:

Hardware emulation of 68000
Using the Z80a source code from the AmiMSX Emulator
Using HAM8 mode for the NeoGeo graphics

Would this be possible (at usable speed). Or am i barking up the wrong tree.

Regards,

Depending on how the 68000 / Z80 interact its probably easier to emulate both in software (yes, even the 680x0).

Hardware emulation of the 68000 (assuming you mean "run 68K code directly on the 680x0) might be problematic if certian instructions are used (eg TAS). You'd also almost certianly need to use the MMU to fake the address space of the hardware you are emulating.

HAM8 for graphics is always going to be a pain in the backside. RGB->HAM8 encoding is not a trivial process and would eat a lot of CPU. Algorithms do exist, eg RGB15 -> HAM8 c2p; but to be useable you are talking about 68040+

On a good 68060, however, a well programmed emulation might function at workable speed.

A PPC/RTG version might just be a bit more useful, however.

[Karlos]

CU_AMiGA wrote:

If this was emualted like Shapshifter, i just know NeoGeo and MegaDrive emulation is possible! :-)

Don't hold your breath there. Shapeshifter works because the emulated mac has very little custom hardware to worry about (and what there is is generally accesed through API's in the macos, hence very easy to replace) and also doesn't depend on any specific 680x0 being present in the emulated machine.

For consoles, especially of this vintage, it's often the case that the overall system is much more complex. You have a lot of custom hardware to emulate (usually without the benefit of any insulating APIs provided by the console's firmware/kernel) and even then, software may depend on exact timing of the components too which you are simply not going to get on your emulation.

As crazy as it may sound, it's often simpler to emulate the lot in software than it is to attempt to use native hardware for a particular task.

[Karlos]

CU_AMiGA wrote:
Okay so draw the line for me:

Wooult it be possible to do 68000 hardware emulation, or are you saying its IMPOSSIBLE?!

Of course it is possible. The problem is it is likely to be so complex and awkward to "get right" when considering all other factors that it is effectively impossible. Even if it were accomplished, the chance of it being any faster (considering all the other bottlenecks) are almost nill and there are likely to be far more incompatibilities with games than a pure  software emulation.

[Karlos]

bloodline wrote:

No, I mean a real Chunky mode :-D

Imagine the fun you could have had with the copper, blitter *and* a chunky pixel representation?

Of course, you could actually write an emulation for this non existant hardware, then muck about to your hearts content, eh?