2014唐山工业职业技术学院毕业设计封面(7)

基于单片机的光立方电路设计

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89,85,80,75,70,65,59,54,48,42,36,30,24,18,12,6,0,-6,-12,-18,-24,-30,-36, -42,-48,-54,-59,-65,-70,-75,-80,-85,-89,-94,-98,-102,-105,-108,-112,-114, -117,-119,-121,-123,-124,-125,-126,-126,-126,-126,-126,-125,-124,-123, -121,-119,-117,-114,-112,-108,-105,-102,-98,-94,-89,-85,-80,-75,-70,-65, -59,-54,-48,-42,-36,-30,-24,-18,-12,-6,0,6,12,18,24,30,36,42,48,54,59,65,70,

75,80,85,89,94,98,102,105,108,112,114,117,119,121,123,124,125,126,126}; //采样存储序列表 code char LIST_TAB[128] =

{0,64,32,96,16,80,48,112,8,72,40,104,24,88,56,120,4,68,36,100,20,84,52,116, 12,76,44,108,28,92,60,124,2,66,34,98,18,82,50,114,10,74,42,106,26,90,58，122,6,70,38,102,22,86,54,118,14,78,46,110,30,94,62,126,1,65,33,97,17,81,49,113,9,73,41,105,25,89,57,121,5,69,37,101,21,85,53,117,13,77,45,109,29,93,61,125,3,67,35,99,19,83,51,115,11,75,43,107,27,91,59,123,7,71,39,103,23,87,55,119,15,79,47,111,31,95,63,127}; uchar i = 0,j = 0,k = 0; // uchar b = 0,p = 0;//anum; //

int Temp_Real = 0,Temp_Imag = 0,temp = 0; //中间临时变量 uint TEMP1 = 0,maxa = 0; //中间临时变量 int xdata Fft_Real[128]; //FFT的实部 int xdata Fft_Image[128]; //FFT的虚部

//uchar xdata LED_TAB2[16]; //记录 漂浮物 是否需要 停顿一下 uchar xdata LED_TAB[16]; //记录红色柱状 //uchar xdata LED_TAB1[16]; //记录 漂浮点

void FFT() //基2fft {

for(i=1; i<=7; i++) /* for(1) */ {

b=1;

b <<=(i-1); //碟式运算，用于计算隔多少行计算例如 第一极 1和2行计算

for(j=0; j<=b-1; j++) /* for (2) */ {

p=1;

p <<= (7-i); p = p*j;

for(k=j; k<128; k=k+2*b) /* for (3) */ {

Temp_Real=Fft_Real[k]; Temp_Imag=Fft_Image[k]; temp=Fft_Real[k+b];

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基于单片机的光立方电路设计

Fft_Real[k]=Fft_Real[k]+((Fft_Real[k+b]*COS_TAB[p])>>7)+((Fft_Image[k+b]*SIN_TAB[p])>>7);

Fft_Image[k]=Fft_Image[k]-((Fft_Real[k+b]*SIN_TAB[p])>>7)+((Fft_Image[k+b]*COS_TAB[p])>>7);

Fft_Real[k+b]=Temp_Real-((Fft_Real[k+b]*COS_TAB[p])>>7)-((Fft_Image[k+b]*SIN_TAB[p])>>7);

Fft_Image[k+b]=Temp_Imag+((temp*SIN_TAB[p])>>7)-((Fft_Image[k+b]*COS_TAB[p])>>7); // 移位.防止溢出. 结果已经是本值的 1/64 Fft_Real[k] >>= 1; Fft_Image[k] >>= 1;

Fft_Real[k+b] >>= 1; Fft_Image[k+b] >>= 1; } } }

for(j=0;j<16;j++) //16分频 {

TEMP1=((((Fft_Real[j+1]*

Fft_Real[j+1]))+((Fft_Image[j+1]*Fft_Image[j+1])))>>1);//求各频段幅值 if(TEMP1<1) TEMP1=0; LED_TAB[j] = TEMP1;

if(LED_TAB[j]>maxa) maxa = LED_TAB[j]; //maxa是本次转换的最大值 }

if(maxa>16) //分级量化 {

maxa /= 16;

for(j=0;j<16;j++)

LED_TAB[j] /= maxa; //LED_TAB[j] = 0; } }

void delay2us(void) //2us延时 {

unsigned char a=0,b=0; for(b=112;b>0;b--)

for(a=113;a>0;a--); }

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