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93 lines
2.8 KiB
93 lines
2.8 KiB
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// TestFFT2048iq.ino for Teensy 4.x
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// Bob Larkin 9 March 2021
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// Generate Sin and Cosine pair and input to IQ FFT.
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// Serial Print out powers of all 4096 bins in
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// dB relative to Sine Wave Full Scale
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// Rev- added i to print; added filters on oscillators. 23 Feb 2022
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// Public Domain
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#include "OpenAudio_ArduinoLibrary.h"
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#include "AudioStream_F32.h"
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int jj = 0;
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// GUItool: begin automatically generated code
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AudioSynthSineCosine_F32 sine_cos1; //xy=76,532
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AudioAnalyzeFFT4096_IQ_F32 FFT4096iq1; //xy=243,532
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AudioOutputI2S_F32 audioOutI2S1; //xy=246,591
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AudioConnection_F32 patchCord1(sine_cos1, 0, FFT4096iq1, 0);
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AudioConnection_F32 patchCord2(sine_cos1, 1, FFT4096iq1, 1);
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// GUItool: end automatically generated code
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void setup(void) {
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Serial.begin(9600);
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delay(1000);
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// The 4096 complex FFT needs 32 F32 memory for real and 32 for imag.
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// Set memory to more than 64, depending on other useage.
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AudioMemory_F32(100);
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Serial.println("FFT4096IQ Test 2");
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sine_cos1.amplitude(1.0f); // Initialize Waveform Generator
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// Pick T4.x bin center
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//sine_cos1.frequency(689.0625f);
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// or pick any old frequency
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sine_cos1.frequency(1000.0f);
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// Engage the identical BP Filters on sine/cosine outputs (true).
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sine_cos1.pureSpectrum(true);
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// Select the output format FFT_POWER, FFT_RMS or FFT_DBFS
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FFT4096iq1.setOutputType(FFT_DBFS);
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// Select the wndow function from these four:
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//FFT4096iq1.windowFunction(AudioWindowNone);
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//FFT4096iq1.windowFunction(AudioWindowHanning4096);
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//FFT4096iq1.windowFunction(AudioWindowKaiser4096, 55.0f);
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FFT4096iq1.windowFunction(AudioWindowBlackmanHarris4096);
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// Uncomment to Serial print window function
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// float* pw = FFT4096iq1.getWindow(); // Print window
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// for (int i=0; i<4096; i++) Serial.println(pw[i], 7);
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// x-Axis direction and offset for sine to I and cosine to Q.
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// If xAxis=0 f=fs/2 in middle, f=0 on right edge
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// If xAxis=1 f=fs/2 in middle, f=0 on left edge
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// If xAxis=2 f=fs/2 on left edge, f=0 in middle
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// If xAxis=3 f=fs/2 on right edge, f=0 in middle
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// xAxis=3 is mathematically proper -fs/2 start to +fs/2 stop.
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FFT4096iq1.setXAxis(0X03);
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FFT4096iq1.setNAverage(5);
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}
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void loop(void) {
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static bool doPrint=true;
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float *pPwr;
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// Print output, once
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if( FFT4096iq1.available() && jj++>2 && doPrint )
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{
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pPwr = FFT4096iq1.getData();
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for(int i=0; i<4096; i++)
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{
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// Serial.print((int)((float32_t)i * 44100.0/4096.0)); // Print freq
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Serial.print(i); // FFT Output index (0, 4095)
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Serial.print(" ");
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Serial.println(*(pPwr + i), 8 );
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}
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doPrint = false;
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}
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if(doPrint)
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{
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Serial.print(" Audio MEM Float32 Peak: ");
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Serial.println(AudioMemoryUsageMax_F32());
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}
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delay(100);
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}
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