Data transfer over audio cable

dbloom · Post by **dbloom** » Tue May 13, 2003 2:27 pm

Normally, data transfer from Dreamcast-->PC requires either a BBA or a serial link (aka coder's cable). Both of these are slightly expensive (BBA is around $150, and coder's cable is near $40 in the US after shipping, et cetera).
Mods, you've probably already armed your anti-piracy thread stun guns [otherwise known as thread locks], but realize that the potential for this runs beyond GDROM ripping, as it could be used, say, in DCLinux to transfer saved data to the PC.
Anyway...
Would it be possible to use an audio cable to do (one way) transfer from Dreamcast to PC (by plugging DC audio line out into a 'Y' adapter, into a PC soundcard's line-in)? Perhaps rudimentary error correction could even be done, by means of a burnt CD generated by the PC-based server software, that requests the retransmitting of bits. Either that, or capturing input from the 'SeaMan' microphone-jack-equipped VMU thingy could potentially also work. This could be a low cost, practical way for data transfer to be done with little cost, for those of us who weren't blessed with BBAs. I'm guessing that at least 300kbit/s could be transfered over an analog, 2-channel audio stream (potentially more).
So, what do you guys think?

BlackAura · Post by **BlackAura** » Tue May 13, 2003 9:43 pm

Erm... Yes, it's possible. Heard of the Commodore 64, Specturm, or any other 8-bit computer that used audio tapes to store data? The problem is that, even with modern systems, it's not exactly fast unless you have a really accurate (and expensive) sound card. I would say that 80kbit/s would be the absolute maximum that you could reliably carry, but I don't really know a lot about how data is encoded as audio, so I could be way off.

And we have no drivers for the SeaMan VMU, as far as I know. Someone might be working on it though.

Interesting idea though. I can truthfully say that it had never occured to me.

Darkfalz · Post by **Darkfalz** » Tue May 13, 2003 11:55 pm

smelialichu · Post by **smelialichu** » Wed May 14, 2003 1:49 am

I think it might be easier to work on data transfer using the DC modem.

SchmuckofNI · Post by **SchmuckofNI** » Wed May 14, 2003 2:57 am

Or the DC Broadband modem considering its 10/100 or so I have heard..

dbloom · Post by **dbloom** » Wed May 14, 2003 7:49 am

smelialichu wrote:I think it might be easier to work on data transfer using the DC modem.

Actually, the DC modem hasn't been hacked by DC Devvers yet. Plus, you'd need line amplification.
Plus, telephones cut out everything outside of 300Hz-3000Hz, which isn't applicable to a linein/out cable. MUCH higher data transfer rates, therefore, should be possible with it.

smelialichu · Post by **smelialichu** » Wed May 14, 2003 7:49 am

DC broadband modem would obviously work well, but it's expensive and hard to find.

dbloom · Post by **dbloom** » Wed May 14, 2003 7:59 am

Right. Thats the reason I am seeing if this could work in the first place - all the other choices aren't affordable. People don't like to pay for stuff. If a way to transfer from DC to PC was standardized and communication software for it was made available, homebrew software could become much more powerful and have much more potential. That's the goal of this - to use something most people already have to enable DC<-->PC communication.