Neogeocd Emulator


Julius

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Now that we got a Z80 and a 68k assembly core it might be possible:

Specs of the NEOGEO CD:

CPU: 16bit 68000chip running at 12Mhz with a 4Mhz Z80 chip helping out. It can handle 4,096 colors on screen at once with three simultaneous playfields.

Sound: 13-channel Yamaha sound chip in stereo.

Memory: 7Mb of DRAM; 512K of VRAM; and 64K of SRAM.

Resolution: 320 x 224

Color Palette: 65,536

Max colors on screen: 4096

Max sprites on screen: 380

Internal RAM: 56 Mbits

CD: Single-speed drive with the ability to play audio CDs.

There is a fullspeed (w/o sound) emu on the DC so why not make one on the GP32 aswell ;)

Click this link for more Informations:
http://www.neogeocd.net/
 
Now that we got a Z80 and a 68k assembly core it might be possible:

Specs of the NEOGEO CD:

CPU: 16bit 68000chip running at 12Mhz with a 4Mhz Z80 chip helping out. It can handle 4,096 colors on screen at once with three simultaneous playfields.

Sound: 13-channel Yamaha sound chip in stereo.

Memory: 7Mb of DRAM; 512K of VRAM; and 64K of SRAM.

Resolution: 320 x 224

Color Palette: 65,536

Max colors on screen: 4096

Max sprites on screen: 380

Internal RAM: 56 Mbits

CD: Single-speed drive with the ability to play audio CDs.

There is a fullspeed (w/o sound) emu on the DC so why not make one on the GP32 aswell ;)

Click this link for more Informations:
http://www.neogeocd.net/
3 letters R-A-M

This is the only thing the GP32 needs that the DC has

I think it is possible, but speed will be slow and loading times would be godawful

its been discussed somewhere else, but I'm not sure where
 
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i think rlyeh is working on it:

Rlyeh: Robster has offered me a free 32m/64m upgrade repeated times, and I'm willing to send him one of my gp32's. As soon as I got it I'll try that neogeo port I did sometime ago ]:) For the rest of users I hope NeoGeo CD would be worthy since RAM is very very limited in this case. Dunno really.

it seem like it would only be possible with the ram upgrade because a neogeo rom is about 15MB big.

(Im going to do the ram-upgrade by myself soon)

Let`s hope :D
 
Is anywhere going to offer the ram upgrade for a paying customer? If someone did this I would be willing to pay ALOT.
 
i think rlyeh is working on it:

Rlyeh: Robster has offered me a free 32m/64m upgrade repeated times, and I'm willing to send him one of my gp32's. As soon as I got it I'll try that neogeo port I did sometime ago ]:) For the rest of users I hope NeoGeo CD would be worthy since RAM is very very limited in this case. Dunno really.

it seem like it would only be possible with the ram upgrade because a neogeo rom is about 15MB big.

(Im going to do the ram-upgrade by myself soon)

Let`s hope :D
Not sure if you understood him correctly, but I think he ment a NeoGeo emulator is not possible without a Ram upgrade, but a NeoGeoCD (a console quite a bit different from the NeoGeo) could be possible.

Anyways that would be really cool if Rlyeh is working on it... maybe it is the 68k project he was talking about in the (other?) interview?
 
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With the CD audio stripped away, I'm guessing some NGCD games might fit into RAM (and none will even approach 128MB), but it's not necessary with a CD-based system - and the data spooling rate off an SMC should kill the NGCD's 1x speed drive.

I believe most NGCD games distributed for use on emulators have their audio repacked as MP3 files, cutting down on filesize. Of course, essentially running an MP3 player on top of a fairly high-spec emulator may be too much for the GP32 to handle...
 
Is anywhere going to offer the ram upgrade for a paying customer? If someone did this I would be willing to pay ALOT.

fist i have to do the ram-upgrade on my own gp32 then i think about doing this :D

mashmods wanted to do the ram-upgrade too but they stoped this projekt due to some problems with getting the ram-chips which is really the biggest problem.

Not sure if you understood him correctly, but I think he ment a NeoGeo emulator is not possible without a Ram upgrade, but a NeoGeoCD (a console quite a bit different from the NeoGeo) could be possible.

i dont know the difference between a neogeo and a neogeoCd could someone explain pls ??
 
Well im not too sure my self, but I do know that NeoGeo was cart based, while CD was CD based :lol: Obviously.

BTW: When do you expect to have your own modded?
 
The normal NeoGeo was basicly just the arcade machine also sold for home-use (extremly expensive), and the NeoGeoCD was a home-use only console that had similar games to the NeoGeo. It was also less expensive but still about $400 I think.
Check the link in my first post.
 
The games are identical, except the CDs have better sound, and sometimes worse graphics

The CD system took a long time to load (unle u had a CDZ which had a 2 speed drive)

Nearly all games released on the AES (cartridge) also cam out on the CD systems for a fraction of the price, but newer game like KOF2000 havent recieved a port (as far as I'm aware) because the CD system has become dated, it is extremely easy to port a game from MVS (arcade) to AES (cart. home) because the hardware is identica, a port to a NGCD system however, required the developer to tweak some of the game so that it would fit load in a reasonable time (they dont anyway) so in the end the developers decided it was not worth it, especially since the average price for anew NGCD game is £30 whereas new NGAES game rarely go for under £200

hope that cleared that up
 
how big are the cd images though
it doesn't make sense to me how the games could run on gp32 even with the ram upgrade
i must not know what im talking about
 
how big are the cd images though
it doesn't make sense to me how the games could run on gp32 even with the ram upgrade
i must not know what im talking about
Since the NGCD itself spooled data off of a disk, an emulator for the GP32 can as well. The NG cart systems - MVS and AES - have games (often exceeding 700 megabits/88 megabytes) packed entirely into a RAM cartridge, which the GP32's 8MB wouldn't be able to handle. Even 64MB wouldn't cut it for many games released from 1999 on.
 
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I believe most NGCD games distributed for use on emulators have their audio repacked as MP3 files, cutting down on filesize. Of course, essentially running an MP3 player on top of a fairly high-spec emulator may be too much for the GP32 to handle...
MP3 decoding isn't as slow as it used to be; the fact that everyone is using it now in embedded applications has lead to some really nice improvements in decompression and decoding stuff.

Unfortunately the really awesome stuff is behind a hail of license fees and NDA's.

It's too bad we can't use Ogg Vorbis; although it sucks up a lot more CPU power the codec is at least open source so we can refine it to run faster and nicer on the GP32 (they have an integer-only version of the codec available on xiph.org).
 
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