STM32f4 FFT

#include "delay.h"

#include "arm_math.h" 
#include"math.h"

#define N 64
#define TEST_LENGTH_SAMPLES 128 
#define PI2 (6.283185307179586476925286766559)
#define PI (3.1415926)

float32_t testInput1[64];
float32_t testInput2[128];
float32_t testInput[128];
static float32_t testOutput[64]; 
static float32_t output[TEST_LENGTH_SAMPLES/2]; 
float32_t phase;


/* ------------------------------------------------------------------ 
* Global variables for FFT Bin Example 
* ------------------------------------------------------------------- */ 
uint32_t fftSize = TEST_LENGTH_SAMPLES/2;   ////这个数只能是1024,256,64,16.是采样点数的一半?        
uint32_t ifftFlag = 0;           ////0是正变换,1是逆变换        
uint32_t doBitReverse = 1; ////这个好像必须是1

/* Reference index at which max energy of bin ocuurs */ 
uint32_t refIndex = 213, testIndex = 0; 

int main()