Connecting IDE disks & ISA (network) card to Dreamcast

[SWAT]

Yes, I plan to do IDE adapter.
Loaders I have different, boot loader on KOS, from SD loader (and in bios loader) without KOS.

[OzOnE]

Hi, all!

I know it's been a long while, but I thought I'd say that I finally got around to getting some DC IDE adapter PCB's made.

I just sent off for 40 PCBs to be manufactured in China, so if they work out OK, it should help us get HDD / CF cards working under Dreamshell.

I don't think I'll have much time to play with the direct FPGA GD Emu again, so while we await @cybdyn's invention, we can try getting IDE drives to work.

Mr SWAT, when the PCB's arrive (might take a while), can I send a couple to you? Do you have time to do a bit of work on Dreamshell?

I'm not sure what was stopping DMA from working before (probably KOS), but I think it will still be much faster than SD card even in PIO mode.

What do you think?

Regards,
OzOnE.

[SWAT]

Of course! I already bought the adapter IDE -> SD Card, but I'm too lazy to solder wires I have a few slots from GD-ROM, I wanted to make a PCB adapter from them, but I do not have the tools now.

[OzOnE]

Great!

I know you might not have much time for this project now, but I'll send you a G1 adapter as soon as the first ones are soldered.

I think you would find it quite easy to add support to Dreamshell, especially just PIO for now.
Those SD adapters should work OK too (if they don't force a DMA mode??). It will be interesting to see what the speed difference is to the serial port.

I'll PM you when the PCBs arrive.

Regards,
Ash.

[cybdyn]

i'm doubt - doesn't the dreamcast will boot properly w/o native gd-rom board?

[SWAT]

In this case only bios mod can help.

[OzOnE]

@cybdyn - the adapter boards will have the ~33MHz oscillator onboard to allow the AICA chip to start up (to get past the blank screen).
Unfortunately, it will still require a BIOS mod to boot from SD if the GD drive is removed.

It's also designed so the GD drive can be plugged in at the same time (although, it will be too high to fit the lid back on. ).

Multiple adapters can be used to extend the "IDE" cable on the GD drive, or plug it directly into a PC.

Have to see what happens when they arrive, but no super-simple way to boot without the GD drive.
(until you finish your board ).

[cybdyn]

hm.. i still doubt that bios mod can off access to gd-rom through standart call functions by replacing pointers before they are called.
but i can be wrong - if dreamshell really does it - it's good. cause bios-mod anyway is cheaper than gd-emu)))

dont know when i finish my board - the question : when i start debug it at least)))

---

btw - i start discover more about ARM controllers, and wanna use one of them in future, i face with a problem of weak tusb3210 controller - that is really 51 core based wuth 128! byte memory )))
so i noticed - the Duenan chosen good parts for his emu Atmel ARM + Cyclone 3.

[OzOnE]

I'm hoping that it will just work the same as Dreamshell, so will use "SD-ISO's" for now. (but much faster loading times, without the stuttering in some games).

Most of the retail games seem to use the BIOS syscalls, so as SWAT said, it was fortunate that he was able to add his Dreamshell code to the BIOS and still allow booting of retail games.

I'm not sure if it will be easy to get it to boot directly from CF / HDD from the original BIOS calls though?

Yes, I really must try more projects with the ARM chips. I've always used PIC or AVR chips, but you can get MUCH better performance from ARM processors.

There are a few Arduino style boards with ARM on them now, and there are also some fantastic boards from Olimex with far better features than the Arduino (80MHz / USB bootloader etc.)

Definitely need a board with both ARM and FPGA for a nice dev board though (for GD Emu projects etc.).

Strange to think that the ARM chip was first developed by the people at Acorn Computers many years ago (Steve Furber / Sophie Wilson).
There are apparently more ARM chips in devices Worldwide now than any other processor. More than about 90% of iPhones / iPads / Android devices use them!

btw, I just got direct HDMI output working from the Gamecube last night! (with a few minor issues)
I should be able to apply this to the DC, and most other consoles where the digital signals are available....
http://www.gc-forever.com/forums/viewtop...966#p17966

OzOnE.

[cybdyn]

i think the board what i've made yet is enough for "touch" to gd-emu, but arm controller can give more performance with less cost fpga. and new type of test board "arm + fpga" is under developing - but it covered by fog of secrets

[OzOnE]

Excellent!

I do hope will we have success with this soon.
It's been way too long having to use these "ancient" CD / GD drives now. lol

Doesn't look like Duenan will ever get around to releasing / selling his boards.
Maybe he never actually got it to boot retail games? (just giving him a "challenge". hehe)

I think the IDE adapters are a nice idea, but I'm sure your FPGA design will be the best way to go.
Most people would pay the extra for your plug-and-play SD card solution (only have to remove the lid and GD drive then, instead of soldering a BIOS).

(The IDE adapters can still be used with Dreamshell without soldering though ofc. Just need to boot from the CD instead).

Best of luck with your board.
I'll send you the latest GD Emu Verilog code when you next get time to work on it.
(can't remember if I sent it to you a few months ago?)

Regards,
OzOnE.
P.S. No word on the adapter PCB's yet, but they said it will take a couple of weeks.

[cybdyn]

thnx, i got you code, i think it has many useful info, but i'll try make my own, anyway i'll show what i make and will ask if it need.

[OzOnE]

Ok, no problem.

I think if you use the nullDC source and try to run the C source on the ARM chip, you'll have much better luck.
I'm pretty sure Duenan would have used chunks of his emulator source for his board?

OzOnE.

[cybdyn]

no ideas what duenan got and how it make his gdemu.

i think my current gd-board can be very useful at stange of developing and debuggin code for IDE to SD adaptor.
i paln load any code to DC by usb, emulate IDE device or access through IDE port to real IDE device, and synchronize my board with pc applicaton for see what stores in registers or write to them what i need.

[OzOnE]

Just a quick update. .....

(being shipped now)

[cybdyn]

cool

[SWAT]

Ohh very nice! It looks perfect!

[cybdyn]

can't wait - when it starts breathing)))

[OzOnE]

Hi, all,

I've just tested the adapter with the CF card code, and it works fine.




There are a few minor issues though...

Firstly, you might notice that the plastic part of the IDE socket (with the notch) is reversed. This is because I wanted the socket on the underside, to make it neater.

I'll see if I can remove and replace the plastic part later instead of cutting a new notch. Some 40-wire IDE cables don't have a notch anyway, and it doesn't matter whether you use a 40-wire IDE or 80-wire "UDMA" cable on the DC.

I'm having a hard time finding the tiny oscillator modules for the adapter...

The footprint on the board is for an Abracon ASF series module, but that is only 5x3mm and I can't seem to find the 33.8688MHz version to buy easily online?

That means the adapter can't currently be used stand-alone, so will need to be used with the GD drive plugged in at the same time.
(The GD drive will end up about an inch higher though.)

EDIT: You can of course connect a (bigger) osc module via the pin header.
I'm not entirely sure if that will allow it to boot into Dreamshell (without the stock GDD connected), so I'll have to find an oscillator that I can test later on.
It's possible to use a slightly faster or slower osc frequency, but that will cause the audio to speed up or slow down too.

The other problem is that the adapter can't be used with the motherboard inside the original case.
I thought I'd taken that into account when I did the design, but it seems I forgot about it and made the board a bit too big...



These are prototypes though, so some of these issues were to be expected.
Also, if you leave the stock heatsink / shield on the mobo, the plastic part of the IDE socket sits touching the shield (but works fine).

The adapter itself works fine for using a CF card adapter and developing the code. (SD / SATA adapter not tested).

It can actually read using both PIO and DMA, but there is that issue with the DMA "busy" flag on the DC never going low?

I also tried plugging the GD drive directly into the PC via a USB adapter, but it of course didn't show anything (even in Disk Management).

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

You can also use two adapters for extending the cable between the mobo and GD drive.
I will test this today, as I need to solder some more plugs / sockets.

@SWAT and @cybdyn - please PM me your addresses and I'll get some adapters sent out to you as soon as I've had chance to solder them.

I'd like to send you TWO adapters each - do you have a preference for the type? (all types will have the IDE port on of course)...

Mobo (bottom) plug + GDD (top) socket.
Mobo (bottom) plug only.
GDD (top) socket only.

Unfortunately, I can't yet sell these to too many people unless they can help with the coding.
Please understand that the above issues will be fixed in the next batch too. These are just dev prototypes atm.

It is already possible to load ELF / BIN programs to run under KOS, so I'm sure it won't be long until we can boot SD-ISO's with them.
But, just in case people don't know...

*** Disclaimer - These are NOT yet booting game images! ***

OzOnE.

---

Oh, thought I'd post a couple more photos, to show how high the GD board "hovers" with the adapter in between...
http://oi39.tinypic.com/2j3mr04.jpg

And here is the IDE cable routed to the CF adapter. It can be made MUCH neater of course, but it's just a test setup...
http://oi41.tinypic.com/2gxnts4.jpg

[cybdyn]

thnx Ozone, but i dont know what to do with your board, only for some test or for help write code. maybe later i ask you if need. but i think there are many questions to you when i start debug my board. anyway you stuff looks good)) will hope SWAT has ideas how to start work with it)))