有無人可以教下我

#include <p30F6014A.h>
#include <dsp.h>
#include "fft.h"

/* Device configuration register macros for building the hex file */
_FOSC(CSW_FSCM_OFF & XT_PLL4); /* XT with 8xPLL oscillator, Failsafe clock off */
_FWDT(WDT_OFF); /* Watchdog timer disabled */
_FBORPOR(PBOR_OFF & MCLR_EN); /* Brown-out reset disabled, MCLR reset enabled */
_FGS(CODE_PROT_OFF); /* Code protect disabled */


/* Extern definitions */
extern fractcomplex sigCmpx[FFT_BLOCK_LENGTH] /* Typically, the input signal to an FFT */
__attribute__ ((section (".ydata, data, ymemory"), /* routine is a complex array containing samples */
aligned (FFT_BLOCK_LENGTH * 2 *2))); /* of an input signal. For this example, */
/* we will provide the input signal in an */
/* array declared in Y-data space. */
/* Global Definitions */
#ifndef FFTTWIDCOEFFS_IN_PROGMEM
fractcomplex twiddleFactors[FFT_BLOCK_LENGTH/2] /* Declare Twiddle Factor array in X-space*/
__attribute__ ((section (".xbss, bss, xmemory"), aligned (FFT_BLOCK_LENGTH*2)));
#else
extern const fractcomplex twiddleFactors[FFT_BLOCK_LENGTH/2] /* Twiddle Factor array in Program memory */
__attribute__ ((space(auto_psv), aligned (FFT_BLOCK_LENGTH*2)));
#endif

int peakFrequencyBin = 0; /* Declare post-FFT variables to compute the */
unsigned long peakFrequency = 0; /* frequency of the largest spectral component */

int main(void)
{
int i = 0;
fractional *p_real = &sigCmpx[0].real ;
fractcomplex *p_cmpx = &sigCmpx[0] ;


#ifndef FFTTWIDCOEFFS_IN_PROGMEM /* Generate TwiddleFactor Coefficients */
TwidFactorInit (LOG2_BLOCK_LENGTH, &twiddleFactors[0], 0); /* We need to do this only once at start-up */
#endif

for ( i = 0; i < FFT_BLOCK_LENGTH; i++ )/* The FFT function requires input data */
{ /* to be in the fractional fixed-point range [-0.5, +0.5]*/
*p_real = *p_real >>1 ; /* So, we shift all data samples by 1 bit to the right. */
*p_real++; /* Should you desire to optimize this process, perform */
} /* data scaling when first obtaining the time samples */
/* Or within the BitReverseComplex function source code */

是不是這一個
我想問怎樣改才能a/d input到fft

C30有FFT的dsplib 可以呼叫使用，手冊吧!!XD

有沒有program可以做到在pic30f6014a 上運行fft

要分析的信號是要從 AD 輸入的，將類比轉成數位後猜可以用 DSP 處理的。

如果我想用fft在dspic30f6014a分析電壓頻率並在lcd monitor 顯示

電壓是不是從板中的a/d input 輸入作測試

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