Mini-FAQ on How-To port MVS to a real NGCD!
Hi Folks!!
Just slammed together a mini-faq on how to port MVS roms to play on a real Neo-Geo CD system (and it really works!!):
MVS to CD Conversion How-To:
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Here's a quick "How-To" to port Neo Geo MVS roms to a real Neo Geo CD system.
Iq_132 has made a quick step-by-step with tools to port MVS roms,
here's his details (taken from a page at the NeoSource Forum):
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First, you must make sure that you are dealing with a very tiny neo-geo rom or
you will end up having to cut a lot of precious data out and will end up with
a glitchy game.
The "P" (M68K program) rom must be less than or equal to 2 Megabytes
The "S" (text) rom must be less than or equal to 128 Kilobytes
The "C" (sprites) rom(s) must be less than or equal to 4 Megabytes total
The "M" (Z80 program) rom must be less than or equal to 64 Kilobytes
The "V" (samples) rom(s) must be less than or equal to 1 Megabyte total
If the roms above are larger than this, you will have to remove and discard part
of the rom.
Now, onto the actual conversion:
M68K Program (P):
1. Byteswap the entire rom (swap byte 1 with byte 2, byte 3 with byte 4, etc..)
2. Swap two sets of bytes at address 0x66 and 0x6A of the program
3. Name your output prg.prg (Can be different)
Sprites (C):
1. Read two bytes from your C1
2. Byteswap the bytes from part 1
3. Read two bytes from your C2
4. Byteswap the bytes from part 3
5. Repeat steps 1-4 until your new rom is 4 Megabytes in size
A. Your output file may be smaller if your roms are tiny
6. Save the ouput file as spr.spr (Can be different)
Text (S):
1. Make sure your S1 rom is within the size-limit boundaries
2. Rename your S1 rom to fix.fix (Can be different)
Z80 Program (M):
1. Make sure your M rom is within the size-limit boundaries
2. Rename your M rom to z81.z80 (Can be different)
Samples (V):
1. You may only use one V rom, so if you have more than one, find a tool to
merge them
2. Make sure your (merged?) V rom is within the size-limit boundaries
3. Rename your V rom to pcm1.pcm (Can be different)
Lastly, you will need a few text files:
- IPL.TXT (This file is very important!)
- ABS.TXT
- BIB.TXT
- CPY.TXT
IPL.TXT is the most important, it tells the Neo-Geo machine which files to
load first, it usually contains something similar to this:
FIX.FIX,0,0
Z81.Z80,0,0
PCM1.PCM,0,0
SPR.SPR,0,0
PRG.PRG,0,0
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After doing all that, you need to take the xxx.PRG file and open it up with
a HEX editor and change 14 bytes. I've checked the "conversion" of JoyJoyKid
of CDoty and found that he changed 14 bytes between 0x0042 to 0x0063, which is
part of the boot sequence (IRQ). I've compared it to the "L.PRG" file found in
"ADK World CD" and the changed bytes matches exacty except the 0x0063 which
CDoty replaced with the byte [E0] instead of byte [32]. The [E0] can be found
in any AES N0xxxx1A.038 ROM.
Here's the list of the bytes to change needed to boot on a real Neo Geo CD:
Adress: Original Byte: New Byte:
-------------------------------------------------------------
0x0042 04 05
0x0043 26 22
0x0046 04 05
0x0047 26 28
0x004A 04 05
0x004B 26 2E
0x004E 04 05
0x004F 26 34
0x0052 04 05
0x0053 26 3A
0x0057 26 F2
0x005B 26 EC
0x005F 26 E6
0x0063 (*) 32 E0
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(*) = The 0x0063 can be changed to either [E0] which tells
the CPU that's the game is a AES version or with [32]
which tell the CPU that's is a MVS/CD version.
Now, with these changes, you will be able to boot any MVS-to-CD port.
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About the JoyJoyKid porting of CDoty, here's all the details i've checked
with a Hex Editor and a "compare files" option after doing a port with
iq_132 tools:
CDoty version: MVS-to-CD port: Hex Compare:
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021_S1.FIX 021_S1.BIN No difference!
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021_M1.Z80 021_M1.BIN 336 additional bytes in the
021_M1.BIN (at the end)
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021_P1.PRG 021_P1.PRG (onced 14 bytes differs. See above.
byteswapped with tool)
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021_PCM.PCM 021_V1.BIN +
021_V2.BIN = No difference!
021_V01.BIN (merge the
the files with a hex
editor)
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021_C1.SPR 021_C1.SPR (onced No difference!
byteswapped with tool)
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Here's a list of port i've made which successely boots on a real Neo-Geo CD
game system (as of August 03, 2006):
Ports made by Sly DC:
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01) Andro Dunos (perfect!)
02) Puzzle de Pon [KaNeRyO port, fixed boot sequence] (perfect!)
03) Puzzle de Pon R (perfect!)
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04) Eight Man (Has a few sound issues)
05) King of the Monsters (has sounds issues)
06) Neo Mr. Do (Has a few sound issues)
07) Panic Bomber (has sounds issues)
08) Pop 'N' Bounce (Has a few sound issues)
-------------------------------------------
09) Blut Engel FRENCH (perfect!) [Translated for myself
]
10) Codename - Blut Engel BETA 050423 (perfect!)
11) Columns (perfect!)
12) Frog Feast (perfect!)
13) Poker Night (perfect!)
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PLEASE don't ask me for any of those ISO's, i won't release them. It's
only for learning how-to port games and for my personnal pleasure since
i'm respecting the works/copyrights of "Homebrewers" and the companies
whom released games for the NEo-Geo AES/MVS/CD.
This document may be copied, in whole or in part, by any means provided
the copyright and contributors sections remain intact and no fee is charged
for the information. Contributors retain the copyright to their individual
contributions.
The data contained here in is provided for [INFORMATIONAL PURPOSES
ONLY!]. No warranty is made with regards to the accuracy of some
informations.
Thanks for reading!
--- Sly DC ---
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