i have my android phone sending 4 different frequencies to the Arduino analog in using the earphones jack.
i need my arduino to find out which frequency is coming in, and do some actions according to the certain frequency.
my question is, how can i extract the input frequency and save it as an integer , (or at least a range ?)
i have downloaded the FFT lib and using fix_fft ()
also went through this discussion but still couldnt figure it out…