基于单片机和dac0832的波形发生器

基于单片机和dac0832的波形发生器仿真电路图（输出正弦波、三角波，锯齿波）主程序：#include<reg52.h>

sbitkey2=P2^2;

sbitkey1=P2^1;

sbitkey0=P2^0;

charflag;

//波型输出标置变量

bittime;

unsignedchari;

int

num;

voidfrequency();

voiddelay(intz)//延时

z毫秒

{

intx,y;

for(x=z;x>0;x--)

for(y=124;y>0;y--);

}

unsignedcharsin(unsignedcharx)//正弦波

{

unsignedcharcodesin_tab[]={0x80,0x83,0x86,0x89,0x8c,0x8f,0x92,0x95,0x98,0x9c,0x9f,0xa2,0xa5,0xa8,0xab,0xae,

//上半周

0xb0,0xb3,0xb6,0xb9,0xbc,0xbf,0xc1,0xc4,0xc7,0xc9,0xcc,0xce,0xd1,0xd3,0xd5,0xd8,

0xda,0xdc,0xde,0xe0,0xe2,0xe4,0xe6,0xe8,0xea,0xec,0xed,0xef,0xf0,0xf2,0xf3,0xf4,

0xf6,0xf7,0xf8,0xf9,0xfa,0xfb,0xfc,0xfc,0xfd,0xfd,0xfe,0xfe,0xff,0xff,0xff,0xff,0xff,

0xff,0xff,0xff,0xff,0xff,0xfe,0xfe,0xfd,0xfd,0xfc,0xfc,0xfb,0xfa,0xf9,0xf8,0xf7,

0xf6,0xf4,0xf3,0xf2,0xf0,0xef,0xed,0xec,0xea,0xe8,0xe6,0xe4,0xe2,0xe0,0xde,0xdc,

0xda,0xd8,0xd5,0xd3,0xd1,0xce,0xcc,0xc9,0xc7,0xc4,0xc1,0xbf,0xbc,0xb9,0xb6,0xb3,

0xb0,0xae,0xab,0xa8,0xa5,0xa2,0x9f,0x9c,0x99,0x96,0x92,0x8f,0x8c,0x89,0x86,0x83,

0x80,

0x80,0x7d,0x7a,0x76,0x73,0x70,0x6d,0x6a,0x67,0x64,0x61,0x5e,0x5b,0x58,0x55,0x52,//下半周期

0x4f,0x4c,0x49,0x46,0x43,0x41,0x3e,0x3b,0x39,0x36,0x33,0x31,0x2e,0x2c,0x2a,0x27,

0x25,0x23,0x21,0x1f,0x1d,0x1b,0x19,0x17,0x15,0x14,0x12,0x10,0x0f,0x0d,0x0c,0x0b,

0x09,0x08,0x07,0x06,0x05,0x04,0x03,0x03,0x02,0x02,0x01,0x01,

0x00,0x00,0x00,

0x00,0x01,0x01,0x02,0x02,0x03,0x03,0x04,0x05,0x06,0x07,0x08,0x09,0x0b,0x0c,0x0d,

0x0f,0x10,0x12,0x13,0x15,0x17,0x18,0x1a,0x1c,0x1e,0x20,0x23,0x25,0x27,0x2a,0x2c,

0x2e,0x30,0x33,0x35,0x38,0x3b,0x3d,0x3e,0x40,0x43,0x46,0x48,0x4b,0x4e,0x51,0x54,

0x57,0x5a,0x5d,0x5f,0x60,0x63,0x66,0x69,0x6b,0x6d,0x6f,0x72,0x74,0x76,0x78,0x7a,0x7e,0x80};

returnsin_tab[x];}

voidDAC0832(unsignedcharx)

{

P1=x;

}

voidmain()

{

chard;

d=1;

TMOD=0X02;

num=10;

TH0=256-num;

//num用来控制采样一个点所用的时间

TL0=256-num;

ET0=1;

//按键接于外部中断0，与中断1

EA=1;

TR0=1;

flag=2;

//开始时有输出

i=0;

while(1)

{

if(key2==0)

//按一下key3，d自加1

{

delay(5);

if(key2==0)

{

while(!key2);

d++;

if(d==21)//当d=21，d变为1

d=1;

}

}

frequency();

if(time==1)

{

time=0;

if(i>255)

i=0;

else

i=i+d;//设置采样间隔

switch(flag)

//当按键1的为输出三角波，按键2时输出正弦波

{

case0:DAC0832(i);break;//当flag=0时，锯齿波

case1:

if(i>127)//当flag=1时，三角波

DAC0832(255-i);

else

DAC0832(i);

break;

case2:DAC0832(sin(i));//当flag=2时，正弦波

break;

default:

break;

}

}

}

}voidtime0()interrupt1

{

TH0=256-num;

TL0=256-num;

time=1;

}

voidfrequency()

{

if(key0==0)//

//key0控制flag，频率选择

{

delay(5);

if(key0==0)//再次检测

{

while(!key0);

//等待按键释放

flag++;

//按一下加1

if(flag==3)//大于2返回0

flag=0;

}

}

if(key1==0)

//检测P21是否按下

{

delay(