1 // sketch_13_07_FFT_Freq
5 const int analogPin = A0;
10 const byte PS_128 = (1 << ADPS2) | (1 << ADPS1) | (1 << ADPS0);
11 const byte PS_16 = (1 << ADPS2);
17 ADCSRA &= ~PS_128; // remove prescale of 128
18 ADCSRA |= PS_16; // add prescale of 16 (1MHz)
24 fix_fft(data, im, 7, 0);
27 Serial.println(findF());
30 void sampleWindowFull()
32 for (int i = 0; i < 128; i++)
34 int val = (analogRead(analogPin) - 512) * GAIN;
42 for (int i = 0; i < 64; i++)
44 data[i] = sqrt(data[i] * data[i] + im[i] * im[i]);
52 for (int i = 1; i < 64; i++)
61 int f = maxIndex * 240;