Go Down

Topic: Serial via Audio (Read 902 times) previous topic - next topic

jazzar

So I was writing on my thesis when I thought, what could be a nice way to control my arduino!

Having recently watched Dollhouse (Joss Wheadon wohoo!) the idea came to my mind to use a microphone on the arduino to decode an audio-track to serial data! As I recently saw, the Android platforms features a serial to Audio-convertor, which was originally intendet to be used with a modified audio-jack I think. But we could always use the speaker directly!

Some research gave me, the Arduino ADC has a maximum resolution of 9600Hz, which would not be enaugh for a baud rate of 9600 (start/stop bits) but should easily be enaugh for 4800 or 2400. So it should be possible to use a midi-creating-sound-program to send different commands to the arduino. It will most probably not sound nice, but could be the most cheap, widest available method for (one-way) wireless communication.

The great thing about this is, that almost any mp3-player can be used to issue commands!

So what do you think?

cheers!

jazzar

-.- I'm not that young actually not to remember modems...

Massively ineffecient OR massively inexpensive! ;-)

It's not about being efficent in any case, its more like adding an interface to a device that naturally hasn't got one. So rather then investing in a smartphone with blutooth capabilities to switch on/off things, I could use my mp3-player.

Has this done before on the arduino? Couldn't find anything about it..

Magician

I my opinion, the idea is make sense. I'd correct a math a little:
with sampling rate 9600 sps arduino capable process frequency up to 4800 Hz, but it doesn't mean baud-rate would be limited with this value.
Using QAM modulation, regular modem can send / receive 33.6 kbits/s bidirectionally, over the voice link 300  - 3400 Hz. So, I'w expect arduino able to reach ~45.0 kbit/s
From theoretical point of view it's all looks O'K, the same time practical realization would require a speaker to generate a sound wave.
Efficiency and size of the speaker not competitive to other means of communication, for example IR led or RF chip.

Go Up
 


Please enter a valid email to subscribe

Confirm your email address

We need to confirm your email address.
To complete the subscription, please click the link in the email we just sent you.

Thank you for subscribing!

Arduino
via Egeo 16
Torino, 10131
Italy