It looks like he is using Look Up Table (LUT) to get a note number from measured frequency.
Data is slightly off, compare to :Piano key frequencies - Wikipedia
Other-way, he would have to get 12-th root, which is quite slow on arduino.
It looks like he is using Look Up Table (LUT) to get a note number from measured frequency.
Data is slightly off, compare to :Piano key frequencies - Wikipedia
Other-way, he would have to get 12-th root, which is quite slow on arduino.