Society of Robots - Robot Forum

Electronics => Electronics => Topic started by: airman00 on March 02, 2008, 10:43:15 PM

Title: Encode serial data on audio file
Post by: airman00 on March 02, 2008, 10:43:15 PM

How can I encode serial data on audio?

For example , if i have stereo audio , and left channel is the serial data, and the right channel is the sound.

I obviously can do the sound. but how to do the serial data part?



My application is this: play a song from an ipod and at the same time decode serial data coming out of it  for prerecorded servo movements.

thanks,
eric

Title: Re: Encode serial data on audio file
Post by: Admin on March 15, 2008, 06:04:15 PM

Quote

How can I encode serial data on audio?

Output the serial data to a microphone attached to your PC.

Or if you are afraid of breaking your PC, to a speaker next to a microphone attached to your PC.

You may need an high speed amplifier . . . like a mosfet or op-amp . . .

Title: Re: Encode serial data on audio file
Post by: izua on March 15, 2008, 06:41:32 PM

depending on the sample frequency (if you use high quality audio, for example) you can add some inaudible frequency and control it in fm, for example. of course, some circuitry should detect that freq and its modulation.