NAOMI GD-ROM content

super56k

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So, I'm not sure if this is the correct section of the forum to post this, but I wanted to share this info none the less. While I am waiting for someone to solve my GD-ROM dilemma:
http://forums.arcade-museum.com/showthread.php?t=222267
...I decided to play around with my Guilty Gear XX GD-ROM.

I always wanted to know what was on a NAOMI GD-ROM but CD-ROM drives can't read them, so I used my Dreamcast:
2012-02-07_12-17-54_9.jpg


Using "Dream Loader", I was able to browse the disc:
2012-02-07_12-14-04_615.jpg


Just for the fun of it, I tried to load each file with the Dreamcast's BIOS and here where the results:

ber.bin = won't load
ggx2.bin = won't load
naomigd.bin = interestingly got all the way to the the Dreamcast boot screen and then the Dreamcast reset. ..hmmm

There is also an audio track on track 2 of the disc that warns you in both Japanese and English, not to insert the disc into a Dreamcast.

Anyway, whatever. I post this info for anyone who cares.
 
The GD-ROM stuff has been rather thoroughly reverse-engineered. In fact, MAME now boots Naomi GD-ROM games, and some are theoretically playable. (That is, if there existed a CPU fast enough to do Naomi LLE in real tme, it would be playable on that theoretical CPU.)

Naomi has a COMPLETELY different booting process from the Dreamcast. The entirety of the disc game data is committed to RAM inside the DIMM module that is dedicated to the purpose, before the game code ever runs. In fact, this RAM is capacitor-backed and lasts a day or two, and if the contents of the RAM is still good, the Naomi skips the GD-ROM entirely and boots the game straight from the copy in RAM. (You can test this yourself: Turn the Naomi on, let it boot from GD-ROM, turn it off, take out the disc, then turn it back on right away. It'll boot right into the game like nothing's wrong.)

Even if we hacked a Dreamcast to boot a Naomi GD-ROM, most (if not all) games would just up and crash right away, as they're expecting a) to be able to access their content from the Naomi DIMM, and not from disc, and b) twice as much RAM as the Dreamcast (4x as much in the case of Naomi 2 games)

An unmodified, unhacked Dreamcast would find, and play, the audio track. The idea was that if someone thought it was a Dreamcast disc, the console would give a meaningful error instead of something cryptic that would otherwise suggest hardware failure. This is pretty common in the console world -- XBox 360 does something similar with a DVD video track at the beginning of its game discs.
 
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The GD-ROM stuff has been rather thoroughly reverse-engineered. In fact, MAME now boots Naomi GD-ROM games, and some are theoretically playable. (That is, if there existed a CPU fast enough to do Naomi LLE in real tme, it would be playable on that theoretical CPU.)

Naomi has a COMPLETELY different booting process from the Dreamcast. The entirety of the disc game data is committed to RAM inside the DIMM module that is dedicated to the purpose, before the game code ever runs. In fact, this RAM is capacitor-backed and lasts a day or two, and if the contents of the RAM is still good, the Naomi skips the GD-ROM entirely and boots the game straight from the copy in RAM. (You can test this yourself: Turn the Naomi on, let it boot from GD-ROM, turn it off, take out the disc, then turn it back on right away. It'll boot right into the game like nothing's wrong.)

Even if we hacked a Dreamcast to boot a Naomi GD-ROM, most (if not all) games would just up and crash right away, as they're expecting a) to be able to access their content from the Naomi DIMM, and not from disc, and b) twice as much RAM as the Dreamcast (4x as much in the case of Naomi 2 games)

An unmodified, unhacked Dreamcast would find, and play, the audio track. The idea was that if someone thought it was a Dreamcast disc, the console would give a meaningful error instead of something cryptic that would otherwise suggest hardware failure. This is pretty common in the console world -- XBox 360 does something similar with a DVD video track at the beginning of its game discs.

Original XBOX does this as well. I knew about the beefier hardware thing and really did not expect the game to run, I just wanted to see if I would get anything at all. Also, I wondered what content was on the disc. I was hoping for a directory with sounds and textures and fun stuff to play with but all I got was a huge binary file and a coupe of presumable applications. :/ I wonder if there would be a way to extract that bin into its resources? IDK, just bored whilst trying to find out wich way to hook my GD-ROM power cable up. I so badly want to play this but don't want to fry my drive. I guess I have a 50/50 chance. :(
 
An unmodified, unhacked Dreamcast would find, and play, the audio track. The idea was that if someone thought it was a Dreamcast disc, the console would give a meaningful error instead of something cryptic that would otherwise suggest hardware failure. This is pretty common in the console world -- XBox 360 does something similar with a DVD video track at the beginning of its game discs.
Do they really think anyone would be that stupid??
 
Do they really think anyone would be that stupid??

I'd make a crack on it being a "stupid Americans" thing, but it's in Japanese too :D

I haven't seen an actual Dreamcast disc in probably 11 years, I don't remember if they had that orange color scheme or if they had their own graphics on the discs for their respective titles.. I suppose I could go look on ebay, but it doesn't really matter that much.

our World Series Baseball ('01) and when we had the GD-ROM version of Virtua Tennis running still would NOT load the game from memory even if you turned it off and back on within a few seconds, it would go through and re-load the entire game every single time btw. clearly the DIMM batteries are dead on both. it's not a major bother... we got DDR and Dance Maniax in our arcade to wait to load anyway, so I'm not going out of my way to drop like $80 each on new batteries for games that people never played lol
 
I'd make a crack on it being a "stupid Americans" thing, but it's in Japanese too :D

I haven't seen an actual Dreamcast disc in probably 11 years, I don't remember if they had that orange color scheme or if they had their own graphics on the discs for their respective titles.. I suppose I could go look on ebay, but it doesn't really matter that much.

our World Series Baseball ('01) and when we had the GD-ROM version of Virtua Tennis running still would NOT load the game from memory even if you turned it off and back on within a few seconds, it would go through and re-load the entire game every single time btw. clearly the DIMM batteries are dead on both. it's not a major bother... we got DDR and Dance Maniax in our arcade to wait to load anyway, so I'm not going out of my way to drop like $80 each on new batteries for games that people never played lol

Man, I'd love to get my hands on a DDR someday. Why does it take so long to load? Is it Naomi, Chihiro or some other incarnation of drive and RAM board?
 
Man, I'd love to get my hands on a DDR someday. Why does it take so long to load? Is it Naomi, Chihiro or some other incarnation of drive and RAM board?

DDR 8th and earlier (as well as all Dance Maniax versions, actually) run on one of two variants of Konami's System 573 hardware (PSX-based but with ground-up custom audio), these two variants are specific to their Bemani games. Sys573 is notorious for taking forever to boot, 20+ minutes is perfectly normal for these computers.

573 is really, really goofy. They run from CD-ROM but also have some stuff in EEPROMs but also have some stuff on a PCMCIA card but all of this stuff is flashed off the CD-ROM so, oh hell, there's maybe six people in the world that fully understand how 573 works. Very very bizarre hardware.
 
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DDR 8th and earlier (as well as all Dance Maniax versions, actually) run on one of two variants of Konami's System 573 hardware (PSX-based but with ground-up custom audio), these two variants are specific to their Bemani games. Sys573 is notorious for taking forever to boot, 20+ minutes is perfectly normal for these computers.

573 is really, really goofy. They run from CD-ROM but also have some stuff in EEPROMs but also have some stuff on a PCMCIA card but all of this stuff is flashed off the CD-ROM so, oh hell, there's maybe six people in the world that fully understand how 573 works. Very very bizarre hardware.

That sounds like a disaster. I thought Naomi was bad.. I wonder why anyone would design something so crazy. At that point, why not just use a PC. I myself like the custom built hardware and its great when they can fit everything on one or two boards. I'm a bit partial to Atari's Flagstaff hardware but I'm sure there is a reason for that. :p
 
doesn't take 20+ minutes, those setups probably have REALLY SHITTY cd-rom drives or something. I would say more like 3-5 minutes, which probably isn't even that long.

major sticking point with any of Konami's hardware is when the RTC fails on their boards. I think Betson's the only place that offers that repair service and it costs a lot to get done.
 
Funny you mention that...

That makes alto more sense to me that some crazy overcomplicated mess.

(In case you're curious, Supernova and Supernova 2 ran on this dirty hack. Yes, that's an off-the-shelf retail PS2.)

I've done a lot of reading on System16 in the past and I remember this hardware. That's pretty lazy IMO and I wonder how reliable that was in the arcade considering all of the issues the original PS2 had. I bet it was funny seeing that game boot up in the arcade.
 
Funny you mention that...

(In case you're curious, Supernova and Supernova 2 ran on this dirty hack. Yes, that's an off-the-shelf retail PS2.)

Thanks for reminding me of the DDR Supernova with the purple Jap PS2 sitting dead in my shop, and the only solution Betson can offer is to replace the entire "computer". They quoted me $825, but I see it is now listed on their website for $995.
 
I bet it was funny seeing that game boot up in the arcade.

The screen, at least on the DDR Supernova with the purple Jap PS2 in it AKA Python 2 - is blanked out until the game starts.
 
Thanks for reminding me of the DDR Supernova with the purple Jap PS2 sitting dead in my shop, and the only solution Betson can offer is to replace the entire "computer". They quoted me $825, but I see it is now listed on their website for $995.

It's unfortunately your only option. The HDD is encrypted and locked to the PS2 unit, and we don't have the appropriate install discs, meaning you need to buy PS2+HDD+software as a set, unless someone cracks the encryption. On the upside, you can sell off the working PS2 as a retail unit, as the whole BIOS is there and it'll run Japanese retail PS2 games no problem.

The screen, at least on the DDR Supernova with the purple Jap PS2 in it AKA Python 2 - is blanked out until the game starts.

Not so much "blanked out" as they use an obscure PS2 BIOS feature to override the system menu and boot directly into the game. Free MC Boot uses the same trick IIRC. Try it -- boot it without the HDD, you'll get a bog standard PS2 menu in Japanese.
 
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I've used FreeMC Boot before. Such a strange feature to allow a console to do. I know the later Slim models got rid of that. As far as replacing the HDD, could you not just ghost another drive with this drives image?
 
I've used FreeMC Boot before. Such a strange feature to allow a console to do. I know the later Slim models got rid of that. As far as replacing the HDD, could you not just ghost another drive with this drives image?

From what I've read, no. It's encrypted against the drive's serial as well as the console's internal key. You need to use special tools (that I'm not 100% sure exist) to decrypt the drive contents and re-encrypt it against the new drive. And these tools need to have direct access to the BIOS of the PS2 that will be running from that HDD, so the tools need to be running on the actual PS2. Sony sure knows how to make things difficult.
 
From what I've read, no. It's encrypted against the drive's serial as well as the console's internal key. You need to use special tools (that I'm not 100% sure exist) to decrypt the drive contents and re-encrypt it against the new drive. And these tools need to have direct access to the BIOS of the PS2 that will be running from that HDD, so the tools need to be running on the actual PS2. Sony sure knows how to make things difficult.

What a disaster. I wonder what they thought they where gaining aside from screwing over people that own the game against future repair. They could have still encrypted the data without a hardware lock so one could restore a drive in real hardware while still protecting their game from bootlegging.
 
What a disaster. I wonder what they thought they where gaining aside from screwing over people that own the game against future repair. They could have still encrypted the data without a hardware lock so one could restore a drive in real hardware while still protecting their game from bootlegging.

Sadly, it's just a built-in feature of the PS2. There's some retail home PS2 games that do this (Final Fantasy XI for instance).
 
I've done a lot of reading on System16 in the past and I remember this hardware. That's pretty lazy IMO and I wonder how reliable that was in the arcade considering all of the issues the original PS2 had. I bet it was funny seeing that game boot up in the arcade.
I've found the PS2 to be a very reliable machine... Never had a single problem with them, I reckon they're great.

As for the HDD issue I wouldn't be surprised if there's a cracked copy floating around which will install on any drive.
 
I've found the PS2 to be a very reliable machine... Never had a single problem with them, I reckon they're great.

As for the HDD issue I wouldn't be surprised if there's a cracked copy floating around which will install on any drive.

If there was, believe me, I'd know about it :( the guys that cracked the BemaniPC six ways to Sunday took a swing at it and didn't get very far because some critical decrypting tools are impossible to find due to the Sony crackdown.
 
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