CAN U REPLACE THE GD ROM WITH

Adri_Magnon · Post by **Adri_Magnon** » Tue Jun 11, 2002 3:20 pm

Hi,

"The GD-ROM (GD for "GigaDisk", referring to the capacity of approx. 1 GB) drive is custom made for SEGA by Yamaha. It uses a regular CD-ROM laser (as opposed to a DVD drive which uses a different wavelength), but has the necessary firmware to access data stored in the proprietary GD-ROM format, which packs the bits more densely than on a normal Yellow Book CD.

A GD-ROM disk actually consits of two data regions, separated by a data-less separator ring. The inner region contains a normal Yellow Book CD-ROM track, and a Red Book CD-DA track. This region can be read in any CD drive. The outer region (outside the separator ring) is the high-density area which contains the actual game data (both files and CD-DA audio).

What little information is known about the GD-ROMs originate mainly from this Powerpoint presentation made by SEGA techs:"

The site has links to the presentations.

http://mc.pp.se/dc/gdrom.html

What I want to know is how to double my RAM in the DC (minus the VideoRam) up to 32MB. Anyone? Anyone? Buehller?

Adrian

brain_donor · Post by **brain_donor** » Tue Jun 11, 2002 3:33 pm

hold on.

brain_donor · Post by **brain_donor** » Tue Jun 11, 2002 3:41 pm

Adri_Magnon wrote:Hi,

"The GD-ROM (GD for "GigaDisk", referring to the capacity of approx. 1 GB) drive is custom made for SEGA by Yamaha. It uses a regular CD-ROM laser (as opposed to a DVD drive which uses a different wavelength), but has the necessary firmware to access data stored in the proprietary GD-ROM format, which packs the bits more densely than on a normal Yellow Book CD.

A GD-ROM disk actually consits of two data regions, separated by a data-less separator ring. The inner region contains a normal Yellow Book CD-ROM track, and a Red Book CD-DA track. This region can be read in any CD drive. The outer region (outside the separator ring) is the high-density area which contains the actual game data (both files and CD-DA audio).

What little information is known about the GD-ROMs originate mainly from this Powerpoint presentation made by SEGA techs:"

The site has links to the presentations.

http://mc.pp.se/dc/gdrom.html

What I want to know is how to double my RAM in the DC (minus the VideoRam) up to 32MB. Anyone? Anyone? Buehller?

Adrian

this is an old topic. I don't mean to insult you but most people here already know this information. there has been discussion before of adding ram to the dreamcast. I think it was decided that the bios would need to be hacked. Dan Potter is working on this here:
http://gamedev.allusion.net/
keep an eye on this. who knows, he may want to add ram too. of course, when the bios can be hacked, you will still need mad solder skills to get the new chips in there and still have them work.

kfazzone01 · Post by **kfazzone01** » Wed Apr 16, 2003 11:03 pm

Is this helpful? gound it while searchin the net.
http://homepages.compuserve.de/bITmASTE ... cdrom.html

Mask of Destiny · Post by **Mask of Destiny** » Thu Apr 17, 2003 3:02 am

I'm pretty sure that the DC-GD interface is proprietary. There is an IDE bus somewhere on the board, but there's a custom Sega chip between it and that little ribbon cable. This, along with the fact that the GD drive runs at 3.3V is going to make it almost impossible to replace the drive.

AND IF THAT IS THE CASE, THEN GUESS WHAT? We could get some tech people working on it (maybe even crackers), and decrypt the GD-ROM's compression. Then we could burn our own GD-ROMs in theory... because we could just compress our data... then use software to emulate the compression on-the-fly (kind of like the glide wrappers)!!!

First of all, it's not compression. It's standard CD format data that's just been crammed closer together. People understand how it works (even better than described in that powerpoint), it is now simply a matter of modifying the firmware of a CD-ROM drive to get it to read a GD. Unfortunately this is no trivial task, but htere are people working on it.

Hashmire420 · Post by **Hashmire420** » Fri Aug 13, 2004 6:53 pm

im goin to hook up my playstations {that was murdered} working cd drive wont it be possible that ill be able to play burnt games now i got december 2000 im going to have to modify it so the correct power wires go to the correct dc plugs but i need to know theres two white whires that dont seem to go to any thing in the gdrom can someone explain these?

Anhaedra · Post by **Anhaedra** » Fri Aug 13, 2004 7:12 pm

Why did you just revive a year old thread?

Hashmire420 · Post by **Hashmire420** » Fri Aug 13, 2004 7:21 pm

i guess your right but rather that than make another thread that makes me look like an idiot where somone tells me to look through old threads and gives me the link to this one

Post by **Roofus** » Fri Aug 13, 2004 7:36 pm

Anhaedra wrote:Why did you just revive a year old thread?

Actually, it's closer to 3 years.

ninja · Post by **ninja** » Fri Aug 13, 2004 7:42 pm

Even if you manage to power the cd-rom drive, your still risking that #1, the drive will even work, and #2, most importantly, that the drive will be able to "communicate" with the dc. This has been discussed many many many times, and in the end, its always a failure. If you have a DC your willing to kill (which is a good possibility), then go ahead and experiment, but dont be surprised if it goes pop zoom bang zing smoke crap its dead.

dcmodder · Post by **dcmodder** » Fri Aug 13, 2004 8:47 pm

ruff ruff ruffffal;sdkjfalskdjf f al;jas grrrrrr!!! threre's not POINT!!!

CAN U REPLACE THE GD ROM WITH

Data on GDROM