Homebrew Wii Neogeo emulation question

Linkuei

Well-Known Member
OP
Newcomer
Joined
Mar 7, 2016
Messages
93
Trophies
0
Age
29
XP
183
Country
Argentina
We still can't run ROMs bigger than 25MB?

I know thats Wii have a limited RAM memory for load biggers ROMs than 25MB, but we still don't have a solution?

We can load CPS2 games bigger than 35MB (Street Fighter Alpha 3) and why not NEOGEO ROMs? I know thats complete different systems technically speaking, but this happens due to a possible lake of optimizations on the Neogeo emulators?
God! Until Nintendo DS could load bigger ROMs with the help of cache files and Wii no!

Someone could explain this to me?
Thanks!
 

cvskid

Well-Known Member
Member
Joined
Apr 13, 2014
Messages
2,808
Trophies
2
XP
3,389
Country
United States
We still can't run ROMs bigger than 25MB?

I know thats Wii have a limited RAM memory for load biggers ROMs than 25MB, but we still don't have a solution?

We can load CPS2 games bigger than 35MB (Street Fighter Alpha 3) and why not NEOGEO ROMs? I know thats complete different systems technically speaking, but this happens due to a possible lake of optimizations on the Neogeo emulators?
God! Until Nintendo DS could load bigger ROMs with the help of cache files and Wii no!

Someone could explain this to me?
Thanks!
Your best bet is neo geo virtual console wii injects.
 
  • Like
Reactions: Linkuei

Santaros

Well-Known Member
Member
Joined
Oct 5, 2013
Messages
196
Trophies
0
Age
44
XP
179
Country
I would say it's not so much a lack of optimization, more that the emulator has been setup to load the entire rom into memory rather than caching it. It wouldn't be something that could be easily fixed without a significant rewrite of the emulator which isn't going to happen at this stage in the Wii's life.
 
  • Like
Reactions: Linkuei

mightymuffy

fatbaldpieeater
Member
Joined
Nov 6, 2002
Messages
1,983
Trophies
3
Age
48
Location
Land o't pies
XP
3,273
Country
United Kingdom
I would say it's not so much a lack of optimization, more that the emulator has been setup to load the entire rom into memory rather than caching it. It wouldn't be something that could be easily fixed without a significant rewrite of the emulator which isn't going to happen at this stage in the Wii's life.
This. Also SF Alpha 3 is run from the zip file, just like Neo Geo roms, and weighs in under 23MB.... one of the Fatal Fury RB runs on Wii and is a larger size than SFA3 (sorry I'm just being a picky bastard :lol:, but the CPS2 emu isn't any more optimized than the Neo Geo in this instance..)
 
  • Like
Reactions: Linkuei

Linkuei

Well-Known Member
OP
Newcomer
Joined
Mar 7, 2016
Messages
93
Trophies
0
Age
29
XP
183
Country
Argentina
Thank you guys!

It's sad that Wii never can load bigger roms since with your 224/240p native resolution + CRT make all the emulators available for him very accurate to the real console experience...
 

nateify

Member
Newcomer
Joined
Oct 23, 2014
Messages
9
Trophies
0
XP
403
Country
United States
It might be a little convoluted, but you could build a PC with an old GPU that can display 240p (or similar) out, and use it with a RGB SCART CRT or with a component transcoder for American TVs. Then you could also use more modern, accurate emulators.
 

Wiimpathy

Well-Known Member
Member
Joined
Mar 3, 2010
Messages
1,013
Trophies
2
XP
3,124
Country
France
Another posibility is injecting NeoGeo romsets (MAME/NeoRAGEx) into Wii VC WADs. Link to my tutorial:
https://gbatemp.net/threads/virtual-console-snk-neogeo-aes-wii-vc-injection-tutorial.548457/

Greetings
Maybe you don't know but not all NeoGeo games can be injected. All latest games(SNK vs Capcom, kof2003 etc) are too large to fit into RAM. That's why I implemented the cache in nand in emulators : https://gbatemp.net/threads/large-neogeo-games-support-and-cps3-tests.493767/
You could still make custom forwarder channels using emulators too.
 
  • Like
Reactions: SaulFabre

SaulFabre

I like Yoshis and the Wii/Wii U scene.
Member
Joined
Feb 6, 2019
Messages
3,173
Trophies
1
Age
25
Location
Ecuador
Website
saulfabreg-wiivc.blogspot.com
XP
7,755
Country
Ecuador
Maybe you don't know but not all NeoGeo games can be injected. All latest games(SNK vs Capcom, kof2003 etc) are too large to fit into RAM. That's why I implemented the cache in nand in emulators : https://gbatemp.net/threads/large-neogeo-games-support-and-cps3-tests.493767/
You could still make custom forwarder channels using emulators too.
Thnaks for the info @Wiimpathy :D
I also knew that largest NeoGeo ROMs cannot be injected. But some latest NeoGeo games (such ZuPaPa (2001)) has small size in its ROM contents.

Greetings
 

SaulFabre

I like Yoshis and the Wii/Wii U scene.
Member
Joined
Feb 6, 2019
Messages
3,173
Trophies
1
Age
25
Location
Ecuador
Website
saulfabreg-wiivc.blogspot.com
XP
7,755
Country
Ecuador
Metal Slug 3 seems quite big (for neo geo), according to this site it has 708 MBit / ~ 88,5 MB. (https://www.neogeokult.com/neo-geo-reviews-us/metal-slug-3-us/)
Shouldn't it be possible to inject neo geo stuff with similar size ? (e.g. Garou which seems to be a little smaller in size with 688 MBit)
That game launched to Wii by Nintendo, by using a new type of game.bin.z compression, I think it's a new type of fast decompression in the NAND, i think it's CR00 compression, but I'm not sure. @sr_corsario is also trying to see what is the type and method of compression in these new game.bin.z, basing on aluigi's code:
Acording with file header, "43 52 30 30" it could be variant of CRUSH compression. "cr00"

CRUSH compression as description : "Powerful LZ featuring extremely fast decompression" (LZ77)

Moreover, nintendo used many times diferents LZ compresion types.

Font:

http://encode.narod.ru/
http://encode.narod.ru/crush001.zip
Quoted from aluigi:

the files have the CR00 magic at the beginning and the rest is encrypted with AES using a key and an ivec.
looks like both are generated for each file... don't know.
anyway even after decrypting the file (the key is correct but it's not that easy to debug) the content means nothing.

if someone is interested the following was my work-in-progress test script for Shock Troopers:
Code:
Code:
idstring "CR00"
#getdstring IVEC 0x10   # ivec or hash or what?
savepos OFFSET
get SIZE asize
math SIZE -= OFFSET
encryption aes "\x88\x2A\x16\xFB\x4E\x08\xD9\x9C\x19\x2D\x98\x68\xEB\xA3\xB7\x99" "\xF4\xC1\x23\xF2\xF3\xAD\x49\xA1\xC3\xC7\xD4\xB1\xE2\x91\x65\x2D"
# "\xD1\xF4\x55\xF2\x0F\x10\x5D\x8A\x0C\x8C\xD3\xFA\x56\x32\x30\xE5" ivec xored with first 16 bytes?
log "test.dat" OFFSET SIZE
or
Code:
Code:
idstring "CR00"
getdstring IVEC 0x10
savepos OFFSET
get SIZE asize
math SIZE -= OFFSET
set IVECX binary "\xD1\xF4\x55\xF2\x0F\x10\x5D\x8A\x0C\x8C\xD3\xFA\x56\x32\x30\xE5"
string IVEC ^= IVECX
encryption aes_128_cbc "\x88\x2A\x16\xFB\x4E\x08\xD9\x9C\x19\x2D\x98\x68\xEB\xA3\xB7\x99" IVEC
log "test.dat" OFFSET SIZE

so nothing is finished and I'm not interested in this thing
Answer (and question) from @sr_corsario:
Any one can do something?¿

Now i can say... each game is encrypted with a diferent key (as we thought) because making a comparison between game.bin.z from pal and japanese version of metal slug 3 they are DIFFERENTS!! but with the same file size...

Bigger roms of NeoGeo won't work on VC sadly with the common methods of injection... :(
Greetings
 
Last edited by SaulFabre,
  • Like
Reactions: mive

Site & Scene News

Popular threads in this forum

General chit-chat
Help Users
  • No one is chatting at the moment.
    NinStar @ NinStar: It will actually make it worse