Connecting IDE disks & ISA (network) card to Dreamcast

[OzOnE]

@cybdyn, I don't mind sending you some adapters anyway, as they might be handy for connection to a standard Dev board etc.

No problem if you don't need any adapters though - I know you already have a good board design which plugs straight into the DC mobo.

Yep, I think SWAT will have some good ideas for this adapter.

There are a few more people on the RetrogamerVX Facebook group who may be interested in getting into DC homebrew programming.
Some of them have good C / C++ experience, so I'll send them a few adapter too.

OzOnE.

[cybdyn]

my board has option "IDE <-> fpga <-> gd-rom conn", i can test your code, or help in developing. so dont count me out)))

i more rather need inforation about "SPI" command set and any details on this low level. also i need few good advices on file system level of SD card. (see P.M)

also - if i get any good result maybe you will be interesting in my board? ))

[cybdyn]

"There is a Linux kernel driver available, so it should be possible to port it to a Windows driver??...
http://www.cs.fsu.edu/~baker/devices/lxr...om/gdrom.c"

i see it's good example - i.m wondering if it was made from real bios call / reverse engineering?

[SWAT]

OzOnE, I sent you my address. Please send what you think is the most comfortable
cybdyn, in the network you can find official docs for Sega SPI, I think them and used. Google it "CDIF131E.DOC".

[cybdyn]

oooops, Ozone, i looked closer to your board and found it has two gd-connectors "male" and "female" for stack with original gd-board, i just thuoght you made it for replace only gd-rom board like my board, that's why i said it.s not necessary for me.
but now i think it can be useful for me too. i'll let you know when i really need it. first of all i need test my board. maybe it'll be enough for me.. we will see

[OzOnE]

Yes, I wanted to make it so it could be used in many different ways...

1. Original GDD + CF / HDD or SD / SATA adapter as slave.
2. Original GDD + FPGA for "spying" on the disk data.
3. FPGA as master (GD emulation).
4. GDD connected directly to a PC (custom driver, for ripping).
5. CF / HDD or SD / SATA adapter as master (Dreamshell / BIOS hack).

So, many different uses.

I will buy some IDE-to-SD and IDE-to-SATA adapters to try soon as well.

OzOnE.

[OzOnE]

OK, the first two adapters have been posted to Mr SWAT today.

It took a while because of this Country's stupid bank holidays, where everything takes a while to get back to normal
(ie. back to the normally overpriced and slow mail system).

I did try a cheap IDE-SATA adapter, but it sets the IDE side as "Master", so clashes with the stock GD drive.
The only way around this is if we can patch the BIOS for stand-alone operation, or if you can find a SATA adapter which supports Slave on the IDE side?

Here's a rough diagram of how to connect the adapters in the two most common ways....



As you can see, the "Normal" method is simple enough.

Another thing that will be improved on the next version is that I should have used four pins for the /RST signals (so you can use two jumpers side-by-side).

More updates soon.
Next thing to try is use two IDE-SATA adapters and see if the cable can be extended using only a SATA cable (and a few other thin wires for the CD Audio)...

DC -> Adapter -> IDE-SATA -> SATA cable -> SATA-IDE -> Adapter -> GD Drive.

EDIT: Oh, and also there is no oscillator on the adapters yet...
A BIOS patch will still be needed for Stand-alone mode, as the stock BIOS checks for the GD status at boot-up.
So, the oscillator alone will generally cause a black screen, or it won't boot into Dreamshell (from the DS BIOS).
I forgot that it only booted without the stock GDD before because I had my FPGA Emu plugged in.

[cybdyn]

1- try see better on IDE-SATA adapter, i think it has jumper or not soldered resistor for select Master / slave. or show pic

2- i think such chian doesnt works - adaptor emulate protocol and do it with standart comand set, but gd-drive use it's native protocol. also SATA is not just a serial ATA - it's very close on soft/cmd level , but in really its new IF. only if we can access to firmware of this adapter and change to expand its capabilities))

[OzOnE]

Yep, I've seen a few with the jumper on which might work. Will be interesting to test later on.
Most of these cheap adapters appear to use the Genesys GL831 chip, which doesn't seem to support "Slave" mode...
http://www.genesyslogic.com/_en/product_01_1.php?id=67

I'll look out for a better SATA adapter and test at some point.

I'm not sure the SATA adapter will work with the GD Drive either. It depends at what "layer" the adapter works at.
The Sega SPI commands are just an extension of the ATAPI packet commands though, so it might just work?

I'll try it tonight.

[cybdyn]

i saw for one of such adapters pdf , it emulates only standart set of IDE comands. as i know SPI is used atapi only as interface but with another protocol or extended. anyway you can try and we will see))

[OzOnE]

I just tried the two SATA adapters between a PC motherboard's IDE port and and an IDE CD-ROM drive, and it works great!

I need to solder some more DC adapters today, but it's looking like it might actually work.
SATA on the Dreamcast, and DC -> SATA -> GDD.

[cybdyn]

cause: cd-rom is standart/normal IDE device. also hdd can work too))