Replace GD-ROM with Flash Card?

I don't know if many of you noticed, but the DC GD-ROM port is a plain standard ATA/IDE port.

The software protocol is likely to be proprietary, but the hardware signaling is industry standard. Someone with knowledge on DVD drive firmware hacking could even mod a existing DVD drive to work with the DC should one made an physical adapter for the connections.

Also, I don't know if any of you noticed that the GD drive controller boards contain industry standard ATAPI chips such the OTI found on the early models (2008) or the SEGA-rebranded TOSHIBA CD-ROM parts on the newer "Samsung" branded GD-ROM units...

They're standard CD-ROM drives with customized circuitry and firmware to be able to handle the GD-ROM format and the SEGA security barcode reading. :shrug:

I posted this a while ago and I have no clue why nobody stickied it up...

http://www.assemblergames.com/forums/showthread.php?t=22189
(Dreamcast VA0 schematics)

I also posted Saturn schematics which gotten stickied almost instantly. :shrug:

 

IIRC SPI protocol is standard I/O (IDE or ATA ?) protocol with some extra commands (SPI SoftReset as an exemple).

FG

 

SPI is another industry standard communication bus, but it's SERIAL. Example is the DC SD card adapter. The SD card is accessed through it's built in SPI mode.

If you see signals in schematics marked as "MISO", "MOSI" and "CLK" that's SPI.

The i2C signal names are SCL/SDA.

ATA/ATAPI are a parallel/multiplexed bus which is another industry standard with a less generic purpose:

Interconnection of mass storage devices such as Hard Drives (Using ATA logical protocol and commands) or Optical storage devices (Using ATAPI logical protocol and commands).

Due to it's parallel nature it has like 20 signal pins (including separated mode selection pins).

Advance on silicon technology allowed for a cheaper interface by encapsulating all these signals into a pair of serial low differential voltage links and that is what gave birth to SATA.

 

By SPI I meant Sega Packet Interface. Sorry for the confusion it might have caused.

FG

 

I see ... I didn't knew they called their protocol/standard that way ... :lol:

 

Interesting site.

 

confirmed working pinout for those wanting to make an adapter:

http://wiki.pcbotaku.com/wiki/Sega_CF_box

 

thanks for the link.. how did you find the pinout link?

 

ok what to do with the info?

 

Build a CF card interface for compatible devices?

 

just doesnt seem to be enough info in my mind

 

how well does the SD adapter work for actually running games at this point?

and I agree with werejag, how do you utilize the CF setup? can it interface directly? how are images written? etc etc.

 

There is an official CF board made by SEGA for the Naomi/Chihiro arcade harder. This would appear to be a way to bypass having to need one.

This is not for Dreamcast usage from what I'm gathering.

 

yes, but a naomi dimm is not a dreamcast, and there is a firmware update also needed to make those cf units with arcade boards, this url is pretty useless

 

so atleast im not the only one that sees this as useless info.

 

It's not useless. It just require that a new BIOS be coded for the Dreamcast (in case anyone is willing to make it work).

The point here is that the schematic proves that it's possible to connect a CF straight to the Dreamcast GD-ROM port without need any extra hardware (it could be feasible to use an FPGA chip to make the Dreamcast see a CF card or SD card as if it was a GD-ROM drive with a disc in it, too which would then dismiss the need of customizing the BIOS...).

 

I could hold up a vacuum tube right now and most of this thread would say its useless. I then go put it on ebay and find it goes for $80 to some audiophile.

Uselessness is in the eye of the uninformed.

 

welll untill someone codes this bios its just info with no wheres to go

 

True that!

 

im all for info but a pinout isnt enough for us to do much of anything. now if we had a schematic and a bit of code from the system that interfaces to this then it would be useful. pretending this is helpful is to be misinformed