Rally Chase CD to Cartridge Conversion
- Thread starter Neo Alec
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uhh no, only a few kilobytes is a lot especially when you multiply it by 8 to get the megabits advertised. Audio samples always eat up a huge chunk of memory on any system, and the player piano rolls that are the songs your music driver will coordinate also take considerable space. M ROM stores the Z80 program, the V ROMs store the samples. On Thrash Rally you have 1536kb for samples, 128kb for the z80 driver + songs. That's a "few k" only in the modern sense 
In fact music data takes so much space that if you check out the CD version, the .z80 file is 64kb.
Wiki says there's only 1mb for samples on your DRAM space, that's 66% of what the cartridge version uses, so they probably just dumped sampled instruments used for bgm to fit. Not much you can do... in fact there shouldn't be much data for playing back those songs via the Yamaha IC anyway, considering the z80 lost half its ROM in the conversion to the .z80 file.
What you'd have to do is to TRAP writes to the z80 on $320000 (https://wiki.neogeodev.org/index.php?title=68k/Z80_communication), write down the commands the CD version sends to the z80 for bgm playback, then do the same on the cartridge version and change the command value loaded for the register write on a hex editor. If the write happens in another function and there's no apparent register load in the code, just follow the stack upwards to see where the callee gets the value sent to the function. Transplanting the proper z80 driver calls (and probably also the function that waits for the CD drive to spin up) is the only viable way to go with this. At least unlike Eight Man you already have a working port and z80 driver from SNK to crib stuff from.
In fact music data takes so much space that if you check out the CD version, the .z80 file is 64kb.Wiki says there's only 1mb for samples on your DRAM space, that's 66% of what the cartridge version uses, so they probably just dumped sampled instruments used for bgm to fit. Not much you can do... in fact there shouldn't be much data for playing back those songs via the Yamaha IC anyway, considering the z80 lost half its ROM in the conversion to the .z80 file.
What you'd have to do is to TRAP writes to the z80 on $320000 (https://wiki.neogeodev.org/index.php?title=68k/Z80_communication), write down the commands the CD version sends to the z80 for bgm playback, then do the same on the cartridge version and change the command value loaded for the register write on a hex editor. If the write happens in another function and there's no apparent register load in the code, just follow the stack upwards to see where the callee gets the value sent to the function. Transplanting the proper z80 driver calls (and probably also the function that waits for the CD drive to spin up) is the only viable way to go with this. At least unlike Eight Man you already have a working port and z80 driver from SNK to crib stuff from.
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Are you answering me? Because I was joking, or trying to. Go paste that explanation to the commenter. I need to find something better to do with my time than making fun of random posts from noobs. I probably need to post less.
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that's good advice regardless
neoVLAD
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I didn't know it waa an option. Do I need it?
neoVLAD
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You probably got matte I can’t tell from your video check when you have time and see maybe it’s gloss I have a friend wanting to do a restore just want to be sure before I tell him what to order
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Oh, I see. You're talking about the vinyl finish. Yeah, it's matte. I don't recall any shiny big reds back in the day. I would consider matte the standard for big red cabs.
neoVLAD
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Thanks I appreciate it
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By the way, I do like this last paragraph you wrote, and the effort. The byte at $107 in Rally Chase CD is 2, so it doesn't just use the original cartridge music calls. I guess they must have left them in though, since the cart music still plays in your conversion using the cartridge Z80 driver.
That commenter seems to think Neo Geo just loads cheap midi files using built-in instruments, although I doubt they thought that far into it. There are later fighting games that had voices cut because they couldn't fit all of the sounds necessary for a given match in the 8 megabits of ram, let alone space left for music samples.
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I linked the fbneo team to the arcade projects thread - so hopefully they figured things out.
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That thread had links to the complete roms, so it should be okay. Thanks.
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No problem, glad you enjoyed it!Thank you for this games.
geladobom
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Send it to hbmame.
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Edit: tldr: Here are the four files to replace in your Thrash Rally rom set to convert it to Rally Chase:
File on MEGA
mega.nz
File on MEGA
mega.nz
File on MEGA
mega.nz
File on MEGA
mega.nz
And here's a .neo you can add to your set:
File on MEGA
mega.nz
DarkSoft version:
2.27 MB file on MEGA
mega.nz
ORIGINAL MESSAGE:
Has anyone ever tried to convert Rally Chase from the Neo Geo CD to cartridge? It's a single-load game with one PRG file. The CD version has a few differences: Some cars have manual shifting, I think it's easier. I kind of prefer Rally Chase. I thought it would be nice to be able to load the Rally Chase rom on the cart system.
Anyway, I tried to convert the RALLY.PRG to cartridge, but I can't get it to boot. Maybe it's because they've replaced all the music calls in the P rom on this game. Is there anyone better at this willing to take a look at it?
When’s this get sent off to Aliexpress for the MVS ‘release’?
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You probably can have one of those sellers who makes the game of your choice do a special order for you.When’s this get sent off to Aliexpress for the MVS ‘release’?
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You can send it, you have my permission
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I'm almost doing that myself
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I'm almost doing that myself
Let me know how that works out. ^___^
I really want to play this on a cab.
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your point?