Query if a spectrum analysis is available for reading using read()
fftAnalyzer.available();
1 if a spectrum analysis is available for reading, 0 otherwise.
/*
This example reads audio data from an InvenSense ICS-43432 I2S microphone
breakout board, and prints out the spectrum to the Serial Monitor. The
Serial Plotter built into the Arduino IDE (Tools -> Serial Plotter) can be
used to plot the audio amplitude data.
Circuit:
* Arduino Zero, MKR Zero or MKR1000 board
* ICS-43432:
* GND connected GND
* 3.3V connected 3.3V (Zero) or VCC (MKR1000, MKR Zero)
* WS connected to pin 0 (Zero) or pin 3 (MKR1000, MKR Zero)
* CLK connected to pin 1 (Zero) or pin 2 (MKR1000, MKR Zero)
* SD connected to pin 9 (Zero) or pin A6 (MKR1000, MKR Zero)
created 21 November 2016
by Sandeep Mistry
*/
#include <ArduinoSound.h>
// sample rate for the input
const int sampleRate = 8000;
// size of the FFT to compute
const int fftSize = 128;
// size of the spectrum output, half of FFT size
const int spectrumSize = fftSize / 2;
// array to store spectrum output
int spectrum[spectrumSize];
// create an FFT analyzer to be used with the I2S input
FFTAnalyzer fftAnalyzer(fftSize);
void setup() {
// Open serial communications and wait for port to open:
// A baud rate of 115200 is used instead of 9600 for a faster data rate
// on non-native USB ports
Serial.begin(115200);
while (!Serial) {
; // wait for serial port to connect. Needed for native USB port only
}
// setup the I2S audio input for the sample rate with 32-bits per sample
if (!AudioInI2S.begin(sampleRate, 32)) {
Serial.println("Failed to initialize I2S input!");
while (1); // do nothing
}
// configure the I2S input as the input for the FFT analyzer
if (!fftAnalyzer.input(AudioInI2S)) {
Serial.println("Failed to set FFT analyzer input!");
while (1); // do nothing
}
}
void loop() {
// check if a new analysis is available
if (fftAnalyzer.available()) {
// read the new spectrum
fftAnalyzer.read(spectrum, spectrumSize);
// print out the spectrum
for (int i = 0; i < spectrumSize; i++) {
Serial.print((i * sampleRate) / fftSize); // the starting frequency
Serial.print("\t"); //
Serial.println(spectrum[i]); // the spectrum value
}
}
}