Optimize FFT test input generation

sdk/software/examples/fft/main.c

@@ -5,6 +5,7 @@
 #include <common_func.h>
 #include <confreg_time.h>
 #include <fft.h>
+#include "../fft_test_data.h"
 
 // BSP板级支持包所需全局变量
 unsigned long UART_BASE = 0xbf000000;
@@ -80,12 +81,7 @@ int main(int argc, char** argv)
     float sw_in_im[FFT_POINT_NUM];
 
     for (int i = 0; i < FFT_POINT_NUM; i++) {
-        float dc_part   = 4000.0f;
+        sw_in_re[i] = (float)fft_test_sample((unsigned int)i);
-        float f10_part  = 8000.0f * cos(2 * PI * 10.0 * i / FFT_POINT_NUM);
-        float f200_part = 6000.0f * sin(2 * PI * 200.0 * i / FFT_POINT_NUM);
-        float f400_part = 3000.0f * sin(2 * PI * 400.0 * i / FFT_POINT_NUM);
-        
-        sw_in_re[i] = dc_part + f10_part + f200_part + f400_part;
         sw_in_im[i] = 0.0f;
     }
 

sdk/software/examples/fft_dma/main.c

@@ -8,6 +8,7 @@
 #include <confreg_time.h>
 #include <dma.h>
 #include <fft.h>
+#include "../fft_test_data.h"
 
 // BSP板级支持包所需全局变量
 unsigned long UART_BASE = 0xbf000000;
@@ -93,18 +94,14 @@ int main(int argc, char** argv)
     float sw_in_re[FFT_POINT_NUM];
     float sw_in_im[FFT_POINT_NUM];
 
-    // 初始化测试波形
     for (int i = 0; i < FFT_POINT_NUM; i++) {
-        float dc_part   = 4000.0f;
+        int32_t sample = fft_test_sample((unsigned int)i);
-        float f10_part  = 8000.0f * cos(2 * PI * 10.0 * i / FFT_POINT_NUM);
-        float f200_part = 6000.0f * sin(2 * PI * 200.0 * i / FFT_POINT_NUM);
-        float f400_part = 3000.0f * sin(2 * PI * 400.0 * i / FFT_POINT_NUM);
 
-        sw_in_re[i] = dc_part + f10_part + f200_part + f400_part;
+        sw_in_re[i] = (float)sample;
         sw_in_im[i] = 0.0f;
 
         // 硬件输入需要转为整数存入无缓存内存
-        uncached_in_re[i]  = (int32_t)sw_in_re[i];
+        uncached_in_re[i]  = sample;
         uncached_in_im[i]  = 0;
         
         // 清理输出内存以防干扰

sdk/software/examples/fft_test_data.h

@@ -0,0 +1,80 @@
+#ifndef FFT_TEST_DATA_H
+#define FFT_TEST_DATA_H
+
+#include <stdint.h>
+
+#define FFT_TEST_INPUT_PERIOD 512u
+
+static const int16_t fft_test_input[FFT_TEST_INPUT_PERIOD] = {
+     12000,  19537,  12803,  11425,   4727,   9875,  19249,  12733,
+     10880,   4524,   7132,  17935,  12144,   9543,   3839,   3959,
+     15687,  11133,   7594,   2745,    590,  12673,   9827,   5271,
+      1362,  -2720,   9126,   8377,   2848,   -157,  -5714,   5322,
+      6938,    609,  -1638,  -8154,   1552,   5655,  -1182,  -2905,
+     -9848,  -1895,   4649,  -2305,  -3793, -10662,  -4769,   4007,
+     -2603,  -4173, -10534,  -6871,   3770,  -2002,  -3957,  -9482,
+     -8072,   3932,   -516,  -3110,  -7598,  -8327,   4441,   1752,
+     -1656,  -5045,  -7670,   5204,   4623,    325,  -2039,  -6218,
+      6095,   7850,   2707,   1169,  -4152,   6970,  11144,   5322,
+      4318,  -1704,   7682,  14204,   7982,   7154,    871,   8097,
+     16739,  10488,   9460,   3315,   8107,  18497,  12656,  11071,
+      5391,   7640,  19290,  14327,  11890,   6906,   6674,  19009,
+     15383,  11898,   7730,   5238,  17637,  15758,  11148,   7806,
+      3409,  15251,  15443,   9769,   7155,   1308,  12014,  14483,
+      7945,   5871,   -906,   8167,  12976,   5903,   4115,  -3061,
+      4000,  11061,   3884,   2096,  -4976,   -167,   8906,   2128,
+        54,  -6483,  -4014,   6691,    844,  -1769,  -7443,  -7251,
+      4590,    193,  -3148,  -7758,  -9637,   2761,    269,  -3898,
+     -7383, -11009,   1325,   1093,  -3890,  -6327, -11290,    359,
+      2608,  -3071,  -4656, -10497,   -107,   4684,  -1460,  -2488,
+     -8739,    -97,   7128,    845,     17,  -6204,    317,   9704,
+      3681,   2677,  -3144,   1029,  12152,   6830,   5292,    149,
+      1904,  14218,  10039,   7674,   3376,   2795,  15670,  13045,
+      9656,   6247,   3558,  16327,  15598,  11110,   8516,   4067,
+     16072,  17482,  11957,  10002,   4229,  14871,  18534,  12173,
+     10603,   3992,  12769,  18662,  11793,  10305,   3350,   9895,
+     17848,  10905,   9182,   2344,   6447,  16154,   9638,   7390,
+      1061,   2677,  13714,   8157,   5151,   -377,  -1126,  10720,
+      6637,   2728,  -1827,  -4673,   7409,   5254,    405,  -3133,
+     -7687,   4040,   4160,  -1543,  -4144,  -9935,    867,   3475,
+     -2880,  -4733, -11249,  -1875,   3272,  -3425,  -4803, -11537,
+     -3999,   3567,  -3075,  -4303, -10793,  -5377,   4321,  -1813,
+     -3230,  -9097,  -5949,   5444,    289,  -1630,  -6611,  -5728,
+      6798,   3076,    400,  -3557,  -4800,   8216,   6322,   2729,
+      -206,  -3309,   9519,   9750,   5196,   3156,  -1446,  10527,
+     13061,   7627,   6247,    570,  11084,  15956,   9850,   8817,
+      2519,  11072,  18167,  11711,  10670,   4193,  10422,  19478,
+     13088,  11680,   5421,   9127,  19750,  13899,  11807,   6084,
+      7238,  18929,  14110,  11091,   6125,   4866,  17055,  13739,
+      9656,   5553,   2173,  14256,  12849,   7693,   4444,   -643,
+     10739,  11547,   5442,   2933,  -3367,   6773,   9967,   3169,
+      1196,  -5781,   2663,   8263,   1141,   -560,  -7688,  -1274,
+      6589,   -401,  -2127,  -8927,  -4744,   5086,  -1264,  -3307,
+     -9391,  -7489,   3870,  -1325,  -3935,  -9034,  -9320,   3020,
+      -539,  -3898,  -7880, -10128,   2572,   1053,  -3142,  -6016,
+     -9894,   2517,   3328,  -1682,  -3589,  -8688,   2801,   6090,
+       403,   -791,  -6665,   3335,   9088,   2974,   2156,  -4043,
+      3999,  12043,   5843,   5025,  -1088,   4664,  14665,   8791,
+      7596,   1909,   5198,  16688,  11589,   9682,   4671,   5482,
+     17894,  14016,  11142,   6946,   5427,  18128,  15880,  11898,
+      8539,   4979,  17320,  17034,  11935,   9325,   4129,  15489,
+     17391,  11307,   9264,   2913,  12744,  16927,  10127,   8401,
+      1410,   9274,  15688,   8560,   6858,   -263,   5336,  13781,
+      6803,   4830,  -1967,   1226,  11367,   5066,   2557,  -3547,
+     -2739,   8643,   3555,    306,  -4849,  -6256,   5826,   2446,
+     -1656,  -5739,  -9055,   3133,   1874,  -3091,  -6110, -10929,
+       761,   1915,  -3807,  -5899, -11750,  -1127,   2578,  -3680,
+     -5088, -11478,  -2422,   3806,  -2670,  -3711, -10167,  -3072,
+      5480,   -817,  -1850,  -7956,  -3084,   7429,   1752,    372,
+     -5061,  -2527,   9446,   4843,   2803,  -1750,  -1519,  11309,
+      8206,   5270,   1677,   -216,  12800,  11557,   7599,   4923,
+      1201,  13728,  14611,   9630,   7710,   2555,  13949,  17097,
+     11230,   9813,   3678,  13377,  18793,  12303,  11075,   4432,
+};
+
+static inline int32_t fft_test_sample(unsigned int index)
+{
+    return (int32_t)fft_test_input[index & (FFT_TEST_INPUT_PERIOD - 1u)];
+}
+
+#endif