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DS Misc > Using sound for DS to DS communication?

#130142 - felix123 - Thu May 31, 2007 8:20 am

Since ad-hoc networking is really hard to write, could we use sound instead? The throughput will be really low and it will only work in quiet places, but would it be easier? Maybe encode it into the background music to make it sound less like a modem. :)
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#130149 - spinal_cord - Thu May 31, 2007 9:31 am

you'd have to make a cable to connect the mic/headphone ports to each other.

It'd be fun to see it work though.
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#130155 - Lick - Thu May 31, 2007 10:48 am

I can't go back to wires. Wireless is too awesome.
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#130166 - spinal_cord - Thu May 31, 2007 11:59 am

But as of yet, there is no way to play without a pre-existing network, I say - go for it.
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#130197 - Dood77 - Thu May 31, 2007 8:19 pm

interesting how it would have to be some kind of cross-cable setup:

Code:
mic1--------  ---------mic2
            \/
            /\ 
phone1------  -------phone2


I don't really know much about this kind of thing, but I was thinking... radio, it uses either amplitude or frequency modulation to reproduce sound waves, both of which we can do on a cable out of a headphone jack right? And Wifi uses radio waves, so... wifi driver for headphone/mic? I'm pretty sure this is impossible, but I don't know the technical reasons... there are limitations of the DS sound hardware; music playback quality is pretty limited, as far as I know.

But this sounds harder to do than ad-hoc... I guess if you went the way of infrared, you could transmit raw 1s and 0s with just two signals, on and off. And how hard is it to send/receive raw packets with a predefined header to identify them? (I pretty much know I'm wrong on something here, correct me.)
EDIT: Doh! Why does phpbb insist on deleting contiguous spaces??
EDIT2: Ah, code markup helped ;)
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#130211 - sonny_jim - Thu May 31, 2007 9:46 pm

Dood77 wrote:

I was thinking... radio, it uses either amplitude or frequency modulation to reproduce sound waves, both of which we can do on a cable out of a headphone jack right? And Wifi uses radio waves, so... wifi driver for headphone/mic? I'm pretty sure this is impossible, but I don't know the technical reasons...

The DS sound hardware is not even nearly capable of generating the frequencies needed for RF propagation. I imagine the DS sound hardware is capable of 80Hz- 18000Hz, whereas radio waves are mostly >30KHz. You could use the DS to generate a VLF waveform, but you'd still need an aerial and an amplifier.

Wifi does use radio waves but these are in the GHz range, so not even close to what the sound hardware is capable of.