fft128c.c

F2812 标准FFT算法,128点,256点,512点,1024点FFT算法,具体做法为将库含数FFT.LIB加入的目标项目,加入对应的C含数和头文件,特别注意的FFT算法缓冲去一定要存放在0X80

/* ==============================================================================

System Name:    Real FFT - Software Test Bench (STB)

File Name:      FFTRD.C

Description:    Primary System file for demonstrating the Real FFT module

Originator:     Advanced Embeeded Control (AEC) - Texas Instruments

Target dependency:  x28x

Description:
============

*/

#include "DSP281x_Device.h"
#include "fft.h"
#include "const.h"

#define N_FFT     8

/* Create an Instance of FFT module                 */
#define     N   128
#pragma DATA_SECTION(ipcb, "FFTipcb");
#pragma DATA_SECTION(mag, "FFTmag");

CFFT32  fft=CFFT32_128P_DEFAULTS;

long ipcb[N_FFT][2*N];
long mag[N_FFT][N];

/* Define window Co-efficient Array  and place the
.constant section in ROM memory				*/
const long win[N/2]=HAMMING128;

Uint16 fftflag=0;   //FFT转换启动标志:0不启动；1:启动

extern Uint16 SampleTable[N_SAMPLE+1][N_ANALOG];

void fft_data()
{
    Uint16 i,j;

    if (fftflag==0)
    {
       for (i=0;i<N_FFT;i++)
           for (j=0;j<N;j++)
           {
               ipcb[i][2*j]=((unsigned long)SampleTable[j][2*i])<<16;
           }
       fftflag=1;
    }
}

void fft_subroutine()
{
    Uint16 i;

    if (fftflag==1)     // If the samples are acquired
    {
       for (i=0;i<N_FFT;i++)
       {

   /* Initialize FFT module                            */
           fft.ipcbptr=&ipcb[i][0];
           fft.magptr=&mag[i][0];
           fft.winptr=(long *)win;
           fft.init(&fft);

               {
					CFFT32_brev2(&ipcb[i][0],&ipcb[i][0],N);
//					CFFT32_brev2(&ipcb[i][0],&ipcb[i][0],N);  // Input samples in Real Part

/*					fft.win(&fft);
					CFFT32_brev2(ipcb,ipcb,N);
					CFFT32_brev2(ipcb,ipcb,N);  // Input after windowing
   */
                   fft.izero(&fft);
                   fft.calc(&fft);
                   fft.mag(&fft);
               }

       }
                   fftflag=0;      // Enable the next acquisition
          GpioDataRegs.GPATOGGLE.bit.GPIOA15=1;
    }

}