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Mental2k
September 9th, 2004, 16:29
I was just wondering, if we had a bunch of DCs all with BBAs, would it be possible to set them up in a cluster to allow mega processing power? I know its not really of any great use to anyone, but could a prog be written that splits the data off to each individual DC for processing and then they all send it back to that DC, which then puts out to the tv? just wonderin, its'd be good, just to say it was done, if nothing else.

quzar
September 9th, 2004, 17:37
Yes. I dont know how its done with Naomis but they can do it. Theoretically DCs could do it even if NAOMIs couldnt do it on their own, but the fact that there is a way shows it can be done.

Mental2k
September 10th, 2004, 17:28
Now we'll get the emu's running at full speed ;D

Eric
September 10th, 2004, 19:42
it could be a possibility but people want to get emulation working fullspeed on a one system i dont think coders nor Dcemu want people to get fullspeed having 10 dreamcasts connected to each other to get emulation fullspeed although neat very expensive

Mental2k
September 11th, 2004, 04:52
I was being funny eric, dont take everything I say too literally!

Eric
September 11th, 2004, 12:55
lol i thought you were being serious i dont know man some people are kinda weird

Chaotis
November 18th, 2004, 13:17
Heh, I've been wondering and studying the exact same thing for some time now.

Instead of using the expensive adapters for the dc; has anyone been able to to connect a pci ethernet card to the parallel port instead? I've seen bitmaster's work but I'd assume it would be easier and faster to run just the pci.

I'm only taking elte classes in college right now so I don't know much about what ICs to use to do this and such, anyone else working on this sort of thing?

semicolo
November 18th, 2004, 15:12
There were just isa ethernet cards ever connected to the parallel port of the dc, the biggest trouble to connect pci stuff on it is that the dc port is only 16 bits wide (running a pci at 25Mhz is ok).
But it certainly can be done since the BBA contains a realtek 8139 which is a pci chip (maybe it doesn't use 32 bit transfers ? I'll check that)

Well in fact if you want to build a dc cluster, just connect'em together on their parallel interfaces (with some control logic of course).

Chaotis
November 18th, 2004, 20:14
I see what you mean, what does the dreamcast parallel port run at btw, mhz wise? I know I could pull out some hardware and test it myself but it's easier to ask if someone already knows. ^^;

I see how it would be much easier to connect them together in this way, it would seem much more useful to somehow connect this to a computer and have it manage data or something.

Perhaps build a hub that all the dreamcasts could connect to and then some way to connect it a single computer? Staying away from ethernet altogether.

Sorry if I sound too optimistic, I currently have no actual understanding of how processing can be shared between multiple devices when programming is concerned; the logic is about as far as I've gone.

Cap'n 1time
November 18th, 2004, 20:17
its cool, but its kinda pointless... unless you want some kind of clustered linux server.

semicolo
November 19th, 2004, 05:33
The parallel port is 16 bits wide and clocked at 25Mhz, do you have so many dreamcasts ?
On a cluster a software correctly written is distributed on the different nodes.
I know one software called pvm that helps in writing such programs :
http://www.csm.ornl.gov/pvm/pvm_home.html
There must be other ones

Chaotis
November 19th, 2004, 14:42
So that means the parallel can do about 50mb/s if I'm doing my math right. Still seems possible that it could be used in some sort of cluster.

Thanks for the help semicolo, and actually I only have 3 dreamcasts but I know where to pick them up for under 15$ and I'm the type of person who always has to have a project to do.

This may never turn into something useful but that's not why I'm making it. It's just for the coolness factor and to say it's been done and worked.

Rufus
November 19th, 2004, 22:04
For coolness and possibly a large number of people wantiing one, why not design a BBA or LAN adapter that plugs into the parallel port to replace the modem that unfortunately too many of us have to deal with? :)

But some kind of IDE or USB host controller (with drivers for Flash, ext. HD/CD/DVD, Ethernet adapters) would be useful as well - these GDROM drives aren't going to last forever...

semicolo
November 20th, 2004, 04:33
working on it Rufus (but slooooooooooooowly)
I've bought a CPLD and currently stduying the work of bitmaster and the realtek 8139 datasheet.
I'd like to be able to replace the gdrom drive by a standard cd drive, but I don't think we could do it from the parallel port, it'll be directly in place of the gdrom.

Alexvrb
November 20th, 2004, 22:31
working on it Rufus (but slooooooooooooowly)
I've bought a CPLD and currently stduying the work of bitmaster and the realtek 8139 datasheet.
Cool. A BBA-compatible drop-in replacement would obviously by far be the best solution.

I'd like to be able to replace the gdrom drive by a standard cd drive, but I don't think we could do it from the parallel port, it'll be directly in place of the gdrom.Yeah, but do you think you could keep it top loading, using the guts of a common PC optical drive?

semicolo
November 21st, 2004, 05:18
hum no chance to be able to fit some standard pc cdrom mechanical parts in place of the gdrom.
the gdrom is much more compact and, well, it's top loading !
That would be a pain in the @ss to remove the rails.

Chaotis
November 21st, 2004, 11:58
So does anyone have the schematic of a real bba adapter we can work from or are the chips so proprietary that you can't find anything like them right now? I would like to help work on a project to make a new bba as a replacement but I haven't been able to find anything to begin working with except the pinout for the parallel port and few other things. Or perhaps a parallel port adapter that uses the 12mbps usb connection?

Alexvrb
November 21st, 2004, 23:16
hum no chance to be able to fit some standard pc cdrom mechanical parts in place of the gdrom.
the gdrom is much more compact and, well, it's top loading !
That would be a pain in the @ss to remove the rails.Laser assembly too big? What about something from a laptop drive?

semicolo
November 22nd, 2004, 00:25
Well yes a cdrom from a portable could do the job (didn't thought of it :-D)

Chaotis, all I know from the BBA is it contains a realtek 8139 ethernet chip. From the datasheet it seems there's no other way to connect this chip but pci (or cardbus which is some sort of pci).
So there must be some G2-to-Pci chip in the BBA. I'll ask someone to list the chips, if someone here's got a BBA and wants to do some reverse engineering, you're welcome !
I personnaly don't own a BBA.

quzar
November 22nd, 2004, 04:32
Well yes a cdrom from a portable could do the job (didn't thought of it :-D)

Chaotis, all I know from the BBA is it contains a realtek 8139 ethernet chip. From the datasheet it seems there's no other way to connect this chip but pci (or cardbus which is some sort of pci).
So there must be some G2-to-Pci chip in the BBA. I'll ask someone to list the chips, if someone here's got a BBA and wants to do some reverse engineering, you're welcome !
I personnaly don't own a BBA.

BBAs use custom glue chips to work with the chip.

Alexvrb
November 22nd, 2004, 23:03
I've got glue and I've got chips. All we need is some duct tape and we're in business. :P

quzar
November 22nd, 2004, 23:07
I've got glue and I've got chips. All we need is some duct tape and we're in business. *:P

rofl. mmmm glue chips.

semicolo
November 23rd, 2004, 04:12
Darn, anyone's got a BBA and a logic analyzer ?

Chaotis
November 23rd, 2004, 13:41
Yay for duct tape, you can do anything with that stuff. (and some super glue)

If anyone has anything that could help us it would be very much appreciated.

Is there any adapter you can buy that fits the dc parallel port, currently I have my one off the old modem. Just wondering because it would make it kind of hard to build something and then have someone like lik-sang mass produce them otherwise. :-/

Has anyone tried to use one of those 16bit parallel to usb ics to connect to the parallel port? It seems kinda straight forward but if nobody has done it yet I'm guessing there is something I'm not seeing. (I'm a programmer, not a hardware person) Like: http://www.smsc.com/main/catalog/usb3250.html

Kinda backwards how I have to get a coders cable to program the drivers for another connector in order to make and use it... O_<

semicolo
November 24th, 2004, 05:32
See my tutorial for desoldering the connector Chaotis : http://semicolo.free.fr/Dreamcast/tutorial.html ;-)

The software side for usb is a bit more complicated than other i/o ports, but hey it certainly could be done, i'll check the datasheets (first problem is the clock speed, can probably be worked around).

Chaotis
November 24th, 2004, 13:13
Yeah, the clock speed on the chip is 30mhz using all 16 pins and that's faster than the dc parallel port. So I'd assume you could send empty data or however you say there is no data to be sent. (I know how to do this on the low speed usb connections but the higher ones must be different)

I already have my connector off, that's pretty much what I did anyways. ^^; Except I didn't use a soldering iron and just worked it off a pin at a time, worst it could do is pull a pin out which I just stuck back into the connector.

I looked at dreamcast programming papers and haven't been able to find anything that works with the parallel port. Does KOS or the related libraries have support of it or is it just an extension of the maple bus?

Is there any other connection inside the dreamcast that could be used to communicate without outside data? Kinda hard to explain what I mean but I'm looking for another way to send data to/from the dreamcast much faster than the external ports allow.

Yes, I have infinite questions. Thanks all who helps.

semicolo
November 26th, 2004, 05:29
I think there's some ide code in kos (not sure). I know there is freebsd drivers for dc-ide-through-g2.
Anyway basic access to the parallel port is just reading/writing to the correct address.

I don't understand what you mean by "without outside data"
The g2 bus is the fastest bus after the main memory bus, the sound chip is connected on it (thanks Dan Potter for the info).

Alexvrb
November 26th, 2004, 15:52
You're always going to need "outside data" to get started, even if its just a disc that boots the DC and loads the necessary software. After that you can do whatever you want. It'd be so much easier to just leave a disc in the Dreamcast and send everything over either a serial connection or to the expansion bus. Axlen's cable shows great promise and would be plenty fast for most things.

Chaotis
November 26th, 2004, 20:40
Well so far the only way to communicate with outside data is the serial, parallel, controller ports and gdrom. I was wondering if there was any way (highly unlikely) to add something to say the onboard memory and map it. Even though it would actually be sending the data somewhere else instead of it being on ram.

In order to make a cluster effective it has to be able to send data as fast as it would be able to communicate with the harddrive. Or else it would be a lost cause. 50mbps and about another 1.25mbps using the other ports isn't too bad. If we can get it to actually keep up that speed.

Also, upgrading the memory would be very useful if you know of anyone who has already worked in this area.

EDIT: "without outside data" was supposed to be "with outside data"

semicolo
November 27th, 2004, 05:17
The parallele port of the dc is really just a connection on a system bus, thus by connecting address decoders on it, one can communicate by just writing to some defined memory address.
About memory upgrade, I think I've seen work to raise it upto 32Mb by adding the adequate chips and logic, but the hack was really ugly.

timofonic
November 27th, 2004, 10:01
CD? Better DVD with modified firmware for GD...

mrgraves
November 27th, 2004, 11:05
i like to see the dc going online again! a broadband connection and some kind of server software to host games and play online (lets see if the coders here can still play with the dc ;D).

maybe some kailera stuff to play emus vs. other players. its really the last thing if miss on my dc....

Chaotis
November 27th, 2004, 13:30
So what do you think would be easier/better?

A high speed usb connection in place of the modem.
A new ethernet adapter.

To me it seems the usb adapter would be much easier but the ethernet card would end up being more useful... Not sure which way to try and go. O_<

EDIT: Should we maybe start this as a new topic?

mrgraves
November 27th, 2004, 14:21
if the goal is to get a device for playing over lan/www its the only way to do real client/server aps/games in the future.

usb maybe good for transfering data or play in a lan, i am not a fan of usb stuff when we are talking about network solutions. i often have do deal with this stuff @ work and it really suckz same for bluetooth.

Chaotis
November 27th, 2004, 16:54
So could we find an ethernet controller IC that would operate at 12.5mhz and then use a flipflop to run it off the parallel port? No idea what kind of speed this would mean. (hoping there is a way to keep it close to the possible 50mbps the port can supposedly handle)

semicolo
November 28th, 2004, 04:05
the port can do 400Mbps (50MBps), should be enough for a 100Mbps network.

I got some pictures of 2 different BBA and a Lan adaptor from the french board :
http://archives.dc-france.com/materiel/documentation/hard.tar.bz2 (huge files)
http://perso.wanadoo.fr/pryonic/photos/BBAcote.JPG
http://perso.wanadoo.fr/pryonic/photos/BBArecto.JPG
http://perso.wanadoo.fr/pryonic/photos/BBAverso.JPG

(yes a new topic could be fine)