Sending binary data through audio

Hi,

I want to send binary data from my smartphone to an arduino through a sound wave.
It has to come from the smartphone stereo output OTA i can’t use the phone’s jack output.

I’m looking for an arduino circuit and lib which can process this?

you can use this method look here
don't use IR, If you connect your Arduino to a mic and build some sound frequency and play it from your phone, Arduino will understand it, it's just an idea :slight_smile:

Only problem you'll have is timing. The timing of your smartphone and arduino need to be spot on or you'll be in trouble.