51单片机制作的波形发生器

51单片机制作的波形发生器

相信很多朋友都可能接触到一个波型发生器的制作，可能刚刚入门，做的东西也不会说是很复杂。可能就一

个矩形波，或者是三角波。但是网上的很多资料是忽悠

人的，就此，我也提供一个比较完整的波型发生器 C51 原代：

该系统的软件比较典型：包括键盘的应用，显示的

应用和 DA 转换器的应用。本设计中，输出的波形有三种：正弦波，方波，三角波。

方波的输出最为简单，只要按照设定的周期值将输

出的电压改变即可。

三角波的输出也比较简单，单片机的输出只要完成

数字量递增和递减交替进行即可。、

正弦波的输出最麻烦，如果在软件中计算出输出的

各点电压值，将会浪费很多的 CPU 时间，以至于无法满足频率的要求。通常最简单的方法是通过手动的方法计

算出输出各点的电压值，然后在编写程序时以数组的方

式给出。当需要时，只要按照顺序进行输出即可。这种

方法比运算法速度快且曲线的形状修改灵活。在本设计

中将 360 度分为 256 个点，则每两个点之间的间隔为1.4 度，然后计算出每个点电压对应的数字量即可。只

要反复输出这组数据到 DAC0832, 就可以在系统输出端得到想要的正弦波。

具体程序如下：

#include ;

#define uchar unsigned char

#define uint unsigned int

#define DAdata P0

uchar code Sinetab[256]=

{

0x80,0x82,0x84,0x86,0x88,0x8a,0x8c,0x8e,

0x90,0x92,0x94,0x96,0x98,0x9a,0x9c,0x9e,

0xa0,0xa2,0xa4,0xa6,0xa8,0xaa,0xab,0xad,

0xaf,0xb1,0xb2,0xb4,0xb6,0xb7,0xb9,0xba,

0xbc,0xbd,0xbf,0xc0,0xc1,0xc3,0xc4,0xc5,

0xc6,0xc8,0xc9,0xca,0xcb,0xcc,0xcd,0xce,

0xce,0xcf,0xd0,0xd1,0xd1,0xd2,0xd2,0xd3,

0xd3,0xd3,0xd2,0xd2,0xd1,0xd1,0xd0,0xcf,

0xce,0xce,0xcd,0xcc,0xcb,0xca,0xc9,0xc8,

0xc6,0xc5,0xc4,0xc3,0xc1,0xc0,0xbf,0xbd,

0xbc,0xba,0xb9,0xb7,0xb6,0xb4,0xb2,0xb1,

0xaf,0xad,0xab,0xaa,0xa8,0xa6,0xa4,0xa2,

0xa0,0x9e,0x9c,0x9a,0x98,0x96,0x94,0x92,

0x90,0x8e,0x8c,0x8a,0x88,0x86,0x84,0x82, 0x80,0x7d,0x7b,0x79,0x77,0x75,0x73,0x71, 0x6f,0x6d,0x6b,0x69,0x67,0x65,0x63,0x61, 0x5f,0x5d,0x5b,0x59,0x57,0x55,0x54,0x52, 0x50,0x4e,0x4d,0x4b,0x49,0x48,0x46,0x45, 0x43,0x42,0x40,0x3f,0x3e,0x3c,0x3b,0x3a, 0x39,0x37,0x36,0x35,0x34,0x33,0x32,0x31, 0x31,0x30,0x2f,0x2e,0x2e,0x2d,0x2d,0x2c, 0x2c,0x2b,0x2b,0x2b,0x2b,0x2a,0x2a,0x2a, 0x2a,0x2a,0x2a,0x2a,0x2b,0x2b,0x2b,0x2b, 0x2c,0x2c,0x2d,0x2d,0x2e,0x2e,0x2f,0x30, 0x31,0x31,0x32,0x33,0x34,0x35,0x36,0x37, 0x39,0x3a,0x3b,0x3c,0x3e,0x3f,0x40,0x42, 0x43,0x45,0x46,0x48,0x49,0x4b,0x4d,0x4e, 0x50,0x52,0x54,0x55,0x57,0x59,0x5b,0x5d, 0x5f,0x61,0x63,0x65,0x67,0x69,0x6b,0x6d, 0x6f,0x71,0x73,0x75,0x77,0x79,0x7b,0x7d, };

uchar code Triangletab[58]=

{

0x1a,0x21,0x28,0x2f,0x36,0x3d,0x44,0x4b, 0x52,0x59,0x60,0x67,0x6e,0x75,0x7c,0x83,

0x8a,0x91,0x98,0x9f,0xa6,0xad,0xb4,0xbb,

0xc2,0xc9,0xd0,0xd7,0xde,0xe5,

0xde,0xd7,0xd0,0xc9,0xc2,0xbb,0xb4,0xad,

0xa6,0x9f,0x98,0x91,0x8a,0x83,0x7c,0x75,

0x6e,0x67,0x60,0x59,0x52,0x4b,0x44,0x3d,

0x36,0x2f,0x28,0x21,

};

uchar code Squaretab[2]={0x56,0xaa};

uchar code disp1[]=

{

"Sine Wave "

"Triangle Wale "

"Square Wave "

};

uchar idata disp2[16]={"Frequency:

Hz"};

uchar code Coef[3]={10,100,200};

uchar idata WaveFre[3]={1,1,1};

uchar code WaveTH[]=

{

0xfc,0xfe,0xfe,0xff,0xff,0xff,0xff,0xff,0xff,0xff, 0xfc,0xfe,0xfe,0xff,0xff,0xff,0xff,0xff,0xff,0xff,

0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff, };

uchar code WaveTL[]=

{

0xf2,0x78,0xfb,0x3c,0x63,0x7d,0x8f,0x9d,0xa8,0xb1, 0x17,0x0b,0xb2,0x05,0x37,0x58,0x70,0x82,0x90,0x9b, 0x4d,0xa7,0xc4,0xd3,0xdc,0xe2,0xe6,0xea,0xec,0xee };

uchar Wavecount,THtemp,TLtemp;

uchar Waveform;

sbit rs=P2^5;

sbit rw=P2^6;

sbit e=P2^7;

sbit DA=P2^0;

sbit KEY=P3^2;

void delay(uchar i)

{

uchar j;

for(;i>;0;i--)

for(j=20;j>;0;j--);

}

void busy()

{

uchar temp;

temp=0x00;

rs=0;

rw=1;

while((temp&0x80)==0x80) {

P0=0xff;

e=1;

temp=P0;

e=0;

}

}

void WR_Com(uchar temp) {

busy();

rs=0;

rw=0;

P0=temp;

e=1;

e=0;

}

void WR_Data(uchar num)

{

busy();

rs=1;

rw=0;

P0=num;

e=1;

e=0;

}

void disp_lcd(uchar addr,uchar *temp1) {

uchar i;

WR_Com(addr);

delay(100);

for(i=0;i;0;i--)

{

P0=0x30;

rs=0;

rw=0;

e=1;

e=0;

delay(100);

P0=0x38;

rs=0;

rw=0;

e=1;

e=0;

delay(100);

}

void lcd_Reset()

{

WR_Com(0x01);

delay(100);

WR_Com(0x06);

delay(100);

WR_Com(0x0c);

delay(100);

}

void SineOUT(uchar Wavecount) {

DAdata=Sinetab[Wavecount++]; Wavecount=0;

DA=0;

}

void TriangleOUT(uchar Wavecount) {

DAdata=Triangletab[Wavecount++]; if(Wavecount>;57)

Wavecount=0;

DA=0;

DA=1;

}

void SquareOUT(uchar Wavecount) {

DAdata=Squaretab[Wavecount++];

if(Wavecount>;1)

Wavecount=0;

DA=0;

DA=1;

}

void timer() interrupt 1

{

TH0=THtemp;

TL0=THtemp;

if(Waveform==0)

SineOUT(Wavecount); else if(Waveform==1)

TriangleOUT(Wavecount); else if(Waveform==2)

SquareOUT(Wavecount); }

void key_int() interrupt 0 {

uchar keytemp,keytemp1;

uint WaveCoef;

EA=0;

TR0=0;

keytemp1=0;

delay(10);

while(!KEY);

keytemp=~P2&0x1e; keytemp>;>;=1;

while(keytemp!=8)

{

keytemp=~P2&0x1e;

keytemp>;>;=1;

if(keytemp!=keytemp1)

{

keytemp1=keytemp;

switch(keytemp)

{

case 1:

if(++Waveform==3)

Waveform=0;

break;

case 2:

if(++WaveFre[Waveform]==11)

WaveFre[Waveform]=1;

break;

case 4:

if(--WaveFre[Waveform]==0)

WaveFre[Waveform]=10;

break;

}

THtemp=WaveTH[Waveform*16+(WaveFre[Waveform]-1)]; TLtemp=WaveTL[Waveform*16+(WaveFre[Waveform]-1)];

WaveCoef=WaveFre[Waveform]*Coef[Waveform]; disp2[13]=WaveCoef%10+0x30;

WaveCoef/=10;

disp2[12]=WaveCoef%10+0x30;

WaveCoef/=10;

disp2[11]=WaveCoef%10+0x30;

WaveCoef/=10;

disp2[10]=WaveCoef%10+0x30;

WaveCoef/=10;

disp_lcd(0x80,&disp1[Waveform*16]);

disp_lcd(0xc0,disp2);

}

}

TH0=THtemp;

TL0=THtemp;

Wavecount=0;

TR0=1;

}

void main()

{

uint WaveCoef;

uchar i;

lcd_ini();

lcd_Reset();

WaveCoef=WaveFre[Waveform]*Coef[Waveform]; disp2[13]=WaveCoef%10+0x30;

WaveCoef/=10;

disp2[12]=WaveCoef%10+0x30;

WaveCoef/=10;

disp2[11]=WaveCoef%10+0x30;

WaveCoef/=10;

disp2[10]=WaveCoef%10+0x30;

WaveCoef/=10;

disp_lcd(0x80,&disp1[Waveform*16]);

disp_lcd(0xc0,disp2);

i=0;

DAdata=0x00;

DA=0;

TMOD=0x01;

IT0=1;

ET0=1;

EX0=1;

EA=1;

while(1);

}