Replace GD-ROM with Flash Card?

Andy Geezer is selling a Compact Flash Replacement for Naomi GD-ROM drives :dance:

Flyer over at AGS

Is there any way this could be modded to work with a Dreamcast? Or would a specific DC version have to be created? The SD card mod is cool, but it still requires the booting of a GD. This would be awesome as a completely solid-state DC mod/enhancement to replace dying drives.

 

Well, there is a SD adapter in the works already, but I doubt we will see total removal of the GDrom drives, as an operating system is needed to boot these games that comes on a disc. It's called Dreamshell.

Here are some links.

http://the-dreamcast-junkyard.blogspot.com/2009/03/dreamcast-sd-card-adaptor.html

Youtube video showing a nice DIY internal SD reader mod with front loading port.

http://www.youtube.com/watch?v=OZ_YofVjNm4

Edit: I reread your post and see that you meant something that does NOT use a disc to load the Dreamshell OS. A few folks have suggested integrating Dreamshell into the consoles bios itself, but it has not been acheived yet at this point, not even sure if it is even possible quite frankly.

 

What _sd_ posted would obsolete both the SD and BIOS modifications entirely. While the system would think it's accessing a GD-ROM, the data would be coming from a compact flash card instead. It's like a controller adapter - the system thinks it's what it expects to be seen because the intermediate hardware does the translating.

 

Why would you want to buy and modify that thing? It'd cost a fortune AND it'd take additional logic no doubt. Any old FPGA and SD slot is more than suitable for the job, it just takes old fashioned talent.

 

We could make up a bios to make it work and it would be cool just need someone to convert the bios to work and it would be cool but i would miss the loud loading from the gd-rom drive.

 

So now that there's interest in interfacing a PSone with a HDD, how about bringing some of that knowledge/technology to the Dreamcast?

It is possible to boot directly to SD card with a replacement BIOS, but that modification is beyond the capabilities of most users. From what I understand, the SD Loader compatibility isn't that fantastic either.

I'm talking about producing a small PCB that's basically a DC equivalent of the WODE, with either an SD card socket or a USB port for a HDD. The Naomi Compact Flash replacement proves that this must be possible on a retail Dreamcast, surely?

 

The naomi CF works the way it does because of how the naomi has always loaded games. The entire crypted naomi game binary is loaded in one start to finish session and then its run from the ram of the dimm module.

The dreamcast on the other hand does random accesses throughout most games AND it also supports a serial audio stream, something the naomi doesn't.

Hey ho..

 

A GD-ROM emulator FPGA wich uses a SD-CARD or HDD to load GDI files would be feasible with the right talent!
And apparently Deunan (Makaron programmer) got this talent: http://dknute.livejournal.com/24111.html

Just give the guy some time!

Maybe a simple launcher that choose the game on the HDD could be made. (Similar to the Wii/PS3 backup launchers)

FG

 

Really? Please elaborate, that sounds interesting.

 

Nevermind, I found it already.

 

Three years isn't enough time?

Though on his more recent posts I can see that he has been working on interfacing with a Naomi 2 system though it would appear its work with breaking the protection schemes on the cart system as opposed to making a GD-ROM interface. I haven't read through everything quite yet.

I'd love to take this sort of thing up as a college major but I'm not sure I really want to spend a few years churning up the fact I really am not any good at math. At least not good enough to pass Algebra II the first two/three times....

 

does anyone knows why some use smartmedia cards instead of SD's? (i.e. Everdrive or some other flash carts).

 

Everdrives have until this point all used SD cards (to my knowledge). I've seen some GBA flash carts use CF but besides CF having a parallel connection versus serial for SD I don't know why anyone would prefer CF over SD. Except for opportunistic hackers who want something that has an ATA controller built in or doesn't have SD on hand and does a lot of photography.

Though after checking with Google there were GBA carts (amongst others) that used smartmedia. If I had to take a guess? Smartmedia came out in 1995 (five years before SD was gaining ground), was able to be popped into an adapter and read/written to with a standard 3.5" floppy drive and was used in a LOT of digital cameras circa 2000/2001.

Given most of the GB/GBA flash carts were/are designed and made in China it wouldn't surprise me if smartmedia wasn't pretty damned popular there too.

 

oops, sorry, i thought that everdrive used smartmedia...i was confused.
Oh, i found why:
http://www.assemblergames.com/forums/showthread.php?p=456827#post456827
"As you can see it uses CompactFlash and not SD. No matter how much people bitch I am not going to use SD. Believe me, it's for a good reason."

It was CF not smartmedia...doh!

 

I was asking wombat the other day/week if he had pics inside a Naomi compact flash drive. I have a spare DC with a dead laser I'd love to replace with the flash drive gubbins and allegedly the flash drive file system actually pretends to be a GD-ROM too, woot!

I had the idea after taking apart my Naom GD as it is basically a retail laser unit plonked on top of a SCSI / JVS board so I figure the communication protocols for the compact flash bit must be similar if not the same. Gut or bypass the SCSI / JVS to retail DC and hope for the best

EDIT: Looking at the flyer I guess it would mean building an adapter to convert the SCSI to DC ribbon and the JVS to retail means of power, amongst other things, once of which is probably a hacked securty chip like the triforcetools.py network boot mod just in case

The problems you've already mentioned are apparent though, such as the Naomi needs a firmware update to make use of the flash drive so it would maybe need a BIOS hack. I'm not sure the way a NAOMI loads games into RAM is a problem though, as bascally each system will load the ROM in their own ways just using the same interface.

If anyone gets this sort hack working hook me up and I'll butcher my spare DC for a laugh

 

Same here, where do i apply to get the 15 minutes back i wasted reading that thread?

 

Your probably after something like this :



The SCSI connector is converted to a standard IDE pinout.

As it stands it won't run like that with the original v4 bios that supports CF loading tho. Sega added in a little bit of extra spice to stop people easily bootlegging onto standard CF cards.

Thats not to say it's not possible to get round those checks A nice by product of that is you can also use a SD to CF adaptor :dance:

 

God, this would be the most awesome thing ever to happen to Dreamcast hardware wise.

What about the IDE HDD's that folks had made work with LinuxDC? What could be done with those?

 

The Naomi GDROM -> CF system is NOT compatible with the DC at ALL.
The cable you see coming from the board above (the SCSI cable) interfaces with the GD-ROM unit which is quite different from the internals of a DC's drive.

 

Yeah as Splith pointed out (and i did too, earlier in the thread) this is NOT anything to do with Dreamcast. It's purely a homemade equivalent of the standard sega CF adaptor for the sega arcade systems that use a GDrom.