Support for proper GD-ROM images

[Fina]

Believe me, if I could make my own images, I would. Unfortunately, I do not have the cable to do it, and even if I did, I cannot play Skies of Arcadia on my Dreamcast for 10 minutes without it giving me an "insert disc" error, so it might not even be possible for me to make my own images.

 

[hp1978]

This is a great question to me...

Would an exact game image burned with Gigarec or HD-Burn boot on a Dreamcast or even in Chankast?

 

[General Plot]

In Chankast, I can't imagine an HD-burned disc not working properly. That is saying that the uncompressed original ISO works in the emu. The Dreamcast is a little different. Original retail games were burned in reverse (from the outside going in). And all CD backups that boot include a code that tells the DC GD-ROM to read it as in the same fashion as a standard audio CD (since the DC can play CD-DA's, the drive allowed for this possiblity. Plus the DC developers left that capability there on purpose. I can't recall exactly why they did, but it's there.I wonder if that same code that's written into self bootable CD backups can be applied to an HD burn and run successfully. I have thought about that before, but I don't know if anyone has ever tested this theory. I'm sure sooner or later someone might.

 

[mr.saraiva]

In Chankast, I can't imagine an HD-burned disc not working properly. That is saying that the uncompressed original ISO works in the emu. The Dreamcast is a little different. Original retail games were burned in reverse (from the outside going in). And all CD backups that boot include a code that tells the DC GD-ROM to read it as in the same fashion as a standard audio CD (since the DC can play CD-DA's, the drive allowed for this possiblity. Plus the DC developers left that capability there on purpose. I can't recall exactly why they did, but it's there.I wonder if that same code that's written into self bootable CD backups can be applied to an HD burn and run successfully. I have thought about that before, but I don't know if anyone has ever tested this theory. I'm sure sooner or later someone might.

GDs were not burned in reverse.The inner track is readable by normal cd-roms, but it only consists of a data track Mode1 and an audio-track. Game data is on the outter track, which is not readable by normal cd-roms because individual pits are packed more closely. Did you ever see an open dreamcast reading the discs? The gd-rom starts reading it from the inner track, just like a normal cd reader. The reason why a HD-burned disc wouldn't work, is because they're only readable on DVD-ROMs with modified firmware. Getting back on topic, it would be nice if Chankast indeed could use RAW, unmodified dreamcast GD rips. Skies of Arcadia and Grandia II comes to mind, as the backups have a not so good audio quality.

 

[General Plot]

The first session of a DC game (retail) contains the boot code. Once the first session of the disc (retail copy) is loaded, the second session (the high density area) is read from the outside going in. I have read numerous Dreamcast dev manuals that state the track and disc layout formats. Perhaps you should do some studying as well.

 

[mr.saraiva]

The first session of a DC game (retail) contains the boot code. Once the first session of the disc (retail copy) is loaded, the second session (the high density area) is read from the outside going in. I have read numerous Dreamcast dev manuals that state the track and disc layout formats. Perhaps you should do some studying as well.

Yes, the game data is on the outter track, but it's read from the inside going out, just like normal cds. If this weren't true, how would it be able to read "backup" cds?

Ps: read this dev document by sega:
http://www.dreamcasthistory.com/pics/featuresuspics/dcdevtextfiles/GetStart.txt

 

[General Plot]

As I stated in an earlier post, the hardware developers allowed for a code that would instruct the system to read a data disc in the traditional format of a CD. As I said before, I can't recall why this was done, but it was implemented into the DC and discovered by the creators of Utopia Boot Disc (I think that's who discovered it anyways). Since the system can read normal audio CD's, that made the drive already capable of reading discs in that fashion. But until the code was discovered, it was not known how to get the system to read a game or data disc in the same style. Just a note, when you turn on a DC or start Chankast, that red (or blue) swirl that animates as a line starting on the outside rotating counter clokwise inward is not just a coincedence in design. It was designed to replicate how the system reads discs. I've read Sega's original Software Develpment Kit manuals that state that is where the idea came from for how that logo was created.

 

[DarthDazDC]

I'm actually surprised that at the minute there havent been any real attempts to make a gd-rom drive ror hacking firmware.

 

[General Plot]

Too bad we can't get our hands on one of those GD-ROM drives with a SCSI port that Sega gave away. Or even better, the HKT01. But the ideal is, as you stated, a real attempt at a firmware hack.