Android Question How to make a "function generator" using the smartphone sound card?

[amorosik]

At minute 33:20 of this video we see the use of a function generator that exploits the audio output of the telephone
Obviously within the narrow limits of the audible audio band
How to drive the audio section of the telephone and achieve this result with the B4X program?

 

[moty22]

I made a sine wave with B4J, I can't do it with B4A, you may be able to use it as inspiration.
https://www.b4x.com/android/forum/threads/audio-sine-generator.130599/

 

[amorosik]

Thank you very much, now i try