Bogushenko Sasha / Mbed 2 deprecated fir_f32

огшор

Dependencies:   CMSIS_DSP_401 mbed

Fork of fir_f32 by Nikolay Sergeev

main.cpp@1:9b1df0b2507d, 2014-10-03 (annotated)

Committer:
Sergeev
Date:
Fri Oct 03 14:35:00 2014 +0000
Revision:
1:9b1df0b2507d
Parent:
0:b712470aea1d
Child:
2:707eb5bc5dfc
Ura

Who changed what in which revision?

UserRevisionLine numberNew contents of line
Sergeev 0:b712470aea1d 1 #include "mbed.h"
Sergeev 1:9b1df0b2507d 2 #include <ctype.h>
Sergeev 0:b712470aea1d 3 #include "arm_math.h"
Sergeev 1:9b1df0b2507d 4 #include "arm_const_structs.h"
Sergeev 1:9b1df0b2507d 5
Sergeev 1:9b1df0b2507d 6 void arm_cfft_f32(
Sergeev 1:9b1df0b2507d 7 const arm_cfft_instance_f32 * S,
Sergeev 1:9b1df0b2507d 8 float32_t * p1,
Sergeev 1:9b1df0b2507d 9 uint8_t ifftFlag,
Sergeev 1:9b1df0b2507d 10 uint8_t bitReverseFlag);
Sergeev 1:9b1df0b2507d 11
Sergeev 0:b712470aea1d 12
Sergeev 1:9b1df0b2507d 13
Sergeev 1:9b1df0b2507d 14 Serial pc(USBTX, USBRX);
Sergeev 1:9b1df0b2507d 15
Sergeev 1:9b1df0b2507d 16 AnalogIn left(A2);
Sergeev 1:9b1df0b2507d 17 AnalogIn right(A3);
Sergeev 1:9b1df0b2507d 18
Sergeev 1:9b1df0b2507d 19 int SAMPLE_RATE_HZ = 40000; // Sample rate of the audio in hertz.
Sergeev 1:9b1df0b2507d 20 const int FFT_SIZE = 16; // Size of the FFT.
Sergeev 1:9b1df0b2507d 21
Sergeev 1:9b1df0b2507d 22 const static arm_cfft_instance_f32 *S;
Sergeev 1:9b1df0b2507d 23 Ticker samplingTimer;
Sergeev 1:9b1df0b2507d 24 float samples[FFT_SIZE*2];
Sergeev 1:9b1df0b2507d 25 float magnitudes[FFT_SIZE];
Sergeev 1:9b1df0b2507d 26 int sampleCounter = 0;
Sergeev 1:9b1df0b2507d 27
Sergeev 1:9b1df0b2507d 28 void samplingCallback()
Sergeev 1:9b1df0b2507d 29 {
Sergeev 1:9b1df0b2507d 30 /*
Sergeev 1:9b1df0b2507d 31 // Read from the ADC and store the sample data
Sergeev 1:9b1df0b2507d 32 samples[sampleCounter] = (1023 * left) - 511.0;
Sergeev 1:9b1df0b2507d 33 // Complex FFT functions require a coefficient for the imaginary part of the input.
Sergeev 1:9b1df0b2507d 34 // Since we only have real data, set this coefficient to zero.
Sergeev 1:9b1df0b2507d 35 samples[sampleCounter+1] = 0.0;
Sergeev 1:9b1df0b2507d 36 // Update sample buffer position and stop after the buffer is filled
Sergeev 1:9b1df0b2507d 37 sampleCounter += 2;
Sergeev 1:9b1df0b2507d 38 */
Sergeev 1:9b1df0b2507d 39 if (sampleCounter >= FFT_SIZE*2) {
Sergeev 1:9b1df0b2507d 40 samplingTimer.detach();
Sergeev 1:9b1df0b2507d 41 }
Sergeev 1:9b1df0b2507d 42 }
Sergeev 1:9b1df0b2507d 43
Sergeev 1:9b1df0b2507d 44 void samplingBegin()
Sergeev 1:9b1df0b2507d 45 {
Sergeev 1:9b1df0b2507d 46 // Reset sample buffer position and start callback at necessary rate.
Sergeev 1:9b1df0b2507d 47 sampleCounter = 0;
Sergeev 1:9b1df0b2507d 48 samplingTimer.attach_us(&samplingCallback, 1000000/SAMPLE_RATE_HZ);
Sergeev 1:9b1df0b2507d 49 }
Sergeev 1:9b1df0b2507d 50
Sergeev 1:9b1df0b2507d 51 bool samplingIsDone()
Sergeev 1:9b1df0b2507d 52 {
Sergeev 1:9b1df0b2507d 53 return sampleCounter >= FFT_SIZE*2;
Sergeev 0:b712470aea1d 54 }
Sergeev 1:9b1df0b2507d 55
Sergeev 1:9b1df0b2507d 56 int main()
Sergeev 0:b712470aea1d 57 {
Sergeev 1:9b1df0b2507d 58 // Set up serial port.
Sergeev 1:9b1df0b2507d 59 pc.baud (38400);
Sergeev 1:9b1df0b2507d 60
Sergeev 1:9b1df0b2507d 61 // Init arm_ccft_32
Sergeev 1:9b1df0b2507d 62 switch (FFT_SIZE)
Sergeev 1:9b1df0b2507d 63 {
Sergeev 1:9b1df0b2507d 64 case 16:
Sergeev 1:9b1df0b2507d 65 S = & arm_cfft_sR_f32_len16;
Sergeev 1:9b1df0b2507d 66 break;
Sergeev 1:9b1df0b2507d 67 case 32:
Sergeev 1:9b1df0b2507d 68 S = & arm_cfft_sR_f32_len32;
Sergeev 1:9b1df0b2507d 69 break;
Sergeev 1:9b1df0b2507d 70 case 64:
Sergeev 1:9b1df0b2507d 71 S = & arm_cfft_sR_f32_len64;
Sergeev 1:9b1df0b2507d 72 break;
Sergeev 1:9b1df0b2507d 73 case 128:
Sergeev 1:9b1df0b2507d 74 S = & arm_cfft_sR_f32_len128;
Sergeev 1:9b1df0b2507d 75 break;
Sergeev 1:9b1df0b2507d 76 case 256:
Sergeev 1:9b1df0b2507d 77 S = & arm_cfft_sR_f32_len256;
Sergeev 1:9b1df0b2507d 78 break;
Sergeev 1:9b1df0b2507d 79 case 512:
Sergeev 1:9b1df0b2507d 80 S = & arm_cfft_sR_f32_len512;
Sergeev 1:9b1df0b2507d 81 break;
Sergeev 1:9b1df0b2507d 82 case 1024:
Sergeev 1:9b1df0b2507d 83 S = & arm_cfft_sR_f32_len1024;
Sergeev 1:9b1df0b2507d 84 break;
Sergeev 1:9b1df0b2507d 85 case 2048:
Sergeev 1:9b1df0b2507d 86 S = & arm_cfft_sR_f32_len2048;
Sergeev 1:9b1df0b2507d 87 break;
Sergeev 1:9b1df0b2507d 88 case 4096:
Sergeev 1:9b1df0b2507d 89 S = & arm_cfft_sR_f32_len4096;
Sergeev 1:9b1df0b2507d 90 break;
Sergeev 1:9b1df0b2507d 91 }
Sergeev 1:9b1df0b2507d 92 float maxValue = 0.0f;
Sergeev 1:9b1df0b2507d 93 unsigned int testIndex = 0;
Sergeev 1:9b1df0b2507d 94
Sergeev 1:9b1df0b2507d 95 // Begin sampling audio
Sergeev 1:9b1df0b2507d 96 samplingBegin();
Sergeev 1:9b1df0b2507d 97
Sergeev 1:9b1df0b2507d 98 while(1)
Sergeev 1:9b1df0b2507d 99 {
Sergeev 1:9b1df0b2507d 100 // Calculate FFT if a full sample is available.
Sergeev 1:9b1df0b2507d 101 if (samplingIsDone())
Sergeev 1:9b1df0b2507d 102 {
Sergeev 1:9b1df0b2507d 103 // Run FFT on sample data.
Sergeev 1:9b1df0b2507d 104 //arm_cfft_radix2_f32(arm_cfft_radix2_instance_f32*S, samples);
Sergeev 1:9b1df0b2507d 105 arm_cfft_f32(S, samples, 0, 1);
Sergeev 1:9b1df0b2507d 106 for(int i = 0;i < FFT_SIZE*2;++i)
Sergeev 1:9b1df0b2507d 107 printf("% 8.2f ",samples[i]);
Sergeev 1:9b1df0b2507d 108 printf("\r\n");
Sergeev 1:9b1df0b2507d 109 // Calculate magnitude of complex numbers output by the FFT.
Sergeev 1:9b1df0b2507d 110 arm_cmplx_mag_f32(samples, magnitudes, FFT_SIZE);
Sergeev 1:9b1df0b2507d 111 for(int i = 0;i < FFT_SIZE;++i)
Sergeev 1:9b1df0b2507d 112 printf("% 8.2f ",magnitudes[i]);
Sergeev 1:9b1df0b2507d 113 printf("\r\n");
Sergeev 1:9b1df0b2507d 114 arm_max_f32(magnitudes, FFT_SIZE, &maxValue, &testIndex);
Sergeev 1:9b1df0b2507d 115 printf("MAX value at magnitudes[%d] : %+ 8.2f\r\n", testIndex, maxValue);
Sergeev 1:9b1df0b2507d 116 // Wait for user confirmation to restart audio sampling.
Sergeev 1:9b1df0b2507d 117 //pc.getc();
Sergeev 1:9b1df0b2507d 118 wait(1);
Sergeev 1:9b1df0b2507d 119 samplingBegin();
Sergeev 1:9b1df0b2507d 120 }
Sergeev 1:9b1df0b2507d 121 }
Sergeev 0:b712470aea1d 122 }