用单片机产生方波

‘壹’ 求高手 用51单片机输出产生方波的程序

#include"reg52.h"
sbit PWM=P1^0;//定义输出脚
void main()
{
TMOD=0x01; //定时器0工作方式1
TH0=(65536-10000)/256; //12M晶振10MS计时常数
TL0=(65536-10000)%256;
EA=1; //开总中断
ET0=1; //开定时器0中断
TR0=1; //启动定时器0
while(1);

}
//中断函数，启动后每10MS进入一次中断
void T0_time(void) interrupt 1
{
TH0=(65536-10000)/256; //12M晶振10MS计时常数
TL0=(65536-10000)%256;
if(PWM)PWM=0; //输出脚取反
else PWM=1;
}

‘贰’ 如何运用单片机原理制作智能信号发生器，要求产生方波、矩形波、三角波、锯齿波和正弦波。

#include<reg51.h>

#include<absacc.h>

#include<MAX72191.h>

#defineDAC XBYTE[0x7fff] //P2.7接CS

sbitkey0 = P3^2;// 增减切换键

sbitkey1 = P3^3;//个位,十位，百位，千位的控制切换

sbitkey2 = P3^4;// 调整位

sbitkey3 = P3^5;// 波形选择正弦、三角、矩形波，锯齿波

unsignedchar i,j;

unsignedint counter,step,flag;

typedefunsigned int uint;

//定时器0初始化

voidInit_Timer0(void)

{

TMOD = (TMOD & 0XF0) | 0X01;//设置工作方式和定时初始值

TH0 = 0xff;

TL0 = 0x00;

TR0 =1; //启动定时器

ET0 =1;

}

//定义输出波形的代码

unsignedchar code type[4][256]={

{ //正弦波代码

0x00,0x00, 0x00, 0x00, 0x00, 0x00, 0x1, 0x1, 0x2, 0x3, 0x3, 0x4, 0x5, 0x6, 0x7, 0x8,

0x9, 0xb,0xc, 0xd, 0xf, 0x10,0x12,0x13,0x15,0x17,0x19,0x1b,0x1d,0x1f,0x21,0x23,

0x25,0x27,0x2a,0x2c,0x2e,0x31,0x33,0x36,0x39,0x3b,0x3e,0x41,0x43,0x46,0x49,0x4c,

0x4f,0x52,0x55,0x58,0x5b,0x5e,0x61,0x64,0x67,0x6a,0x6d,0x70,0x73,0x76,0x7a,0x7d,

0x80,0x83,0x86,0x89,0x8c,0x8f,0x93,0x96,0x99,0x9c,0x9f,0xa2,0xa5,0xa8,0xab,0xae,

0xb1,0xb4,0xb6,0xb9,0xbc,0xbf,0xc1,0xc4,0xc7,0xc9,0xcc,0xce,0xd1,0xd3,0xd5,0xd8,

0xda,0xdc,0xde,0xe0,0xe2,0xe4,0xe6,0xe8,0xea,0xeb,0xed,0xef,0xf0,0xf1,0xf3,0xf4,

0xf5,0xf6,0xf8,0xf9,0xf9,0xfa,0xfb,0xfc,0xfc,0xfd,0xfd,0xfe,0xfe,0xfe,0xfe,0xfe,

0xfe,0xfe,0xfe,0xfe,0xfe,0xfd,0xfd,0xfc,0xfc,0xfb,0xfa,0xf9,0xf9,0xf8,0xf6,0xf5,

0xf4,0xf3,0xf1,0xf0,0xef,0xed,0xeb,0xea,0xe8,0xe6,0xe4,0xe2,0xe0,0xde,0xdc,0xda,

0xd8,0xd5,0xd3,0xd1,0xce,0xcc,0xc9,0xc7,0xc4,0xc1,0xbf,0xbc,0xb9,0xb6,0xb4,0xb1,

0xae,0xab,0xa8,0xa5,0xa2,0x9f,0x9c,0x99,0x96,0x93,0x8f,0x8c,0x89,0x86,0x83,0x80,

0x7d,0x7a,0x76,0x73,0x70,0x6d,0x6a,0x67,0x64,0x61,0x5e,0x5b,0x58,0x55,0x52,0x4f,

0x4c,0x49,0x46,0x43,0x41,0x3e,0x3b,0x39,0x36,0x33,0x31,0x2e,0x2c,0x2a,0x27,0x25,

0x23,0x21,0x1f,0x1d,0x1b,0x19,0x17,0x15,0x13,0x12,0x10,0xf,0xd, 0xc, 0xb, 0x9,

0x8,0x7, 0x6, 0x5, 0x4, 0x3, 0x3, 0x2, 0x1, 0x1, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00

},

{ //三角波代码

0x2,0x4, 0x6, 0x8, 0xa, 0xc, 0xe, 0x10,0x12,0x14, 0x16, 0x18, 0x1a,0x1c, 0x1e, 0x20,

0x22,0x24, 0x26, 0x28, 0x2a, 0x2c, 0x2e, 0x30,0x32, 0x34, 0x36, 0x38, 0x3a, 0x3c, 0x3e, 0x40,

0x42,0x44, 0x46, 0x48, 0x4a, 0x4c, 0x4e, 0x50,0x52, 0x54, 0x56, 0x58, 0x5a, 0x5c, 0x5e, 0x60,

0x62,0x64, 0x66, 0x68, 0x6a, 0x6c, 0x6e, 0x70,0x72, 0x74, 0x76, 0x78, 0x7a, 0x7c, 0x7e, 0x80,

0x82,0x84, 0x86, 0x88, 0x8a, 0x8c, 0x8e, 0x90,0x92, 0x94, 0x96, 0x98, 0x9a, 0x9c, 0x9e, 0xa0,

0xa2,0xa4, 0xa6, 0xa8, 0xaa, 0xac, 0xae, 0xb0,0xb2, 0xb4, 0xb6, 0xb8, 0xba, 0xbc,0xbe, 0xc0,

0xc2,0xc4, 0xc6, 0xc8, 0xca, 0xcc, 0xce, 0xd0,0xd2, 0xd4, 0xd6, 0xd8, 0xda, 0xdc,0xde, 0xe0,

0xe2,0xe4, 0xe6, 0xe8, 0xea, 0xec, 0xee, 0xf0,0xf2, 0xf4, 0xf6, 0xf8, 0xfa, 0xfc,0xfe, 0xff,

0xfe,0xfc, 0xfa, 0xf8, 0xf6, 0xf4, 0xf2, 0xf0,0xee, 0xec, 0xea, 0xe8, 0xe6, 0xe4,0xe2, 0xe0,

0xde,0xdc, 0xda, 0xd8, 0xd6, 0xd4, 0xd2, 0xd0,0xce, 0xcc, 0xca, 0xc8, 0xc6, 0xc4,0xc2, 0xc0,

0xbe,0xbc, 0xba, 0xb8, 0xb6, 0xb4, 0xb2, 0xb0,0xae, 0xac, 0xaa, 0xa8, 0xa6, 0xa4,0xa2, 0xa0,

0x9e, 0x9c, 0x9a, 0x98, 0x96, 0x94, 0x92, 0x90,0x8e, 0x8c, 0x8a, 0x88, 0x86, 0x84, 0x82, 0x80,

0x7e, 0x7c, 0x7a, 0x78, 0x76, 0x74, 0x72, 0x70,0x6e, 0x6c, 0x6a, 0x68, 0x66, 0x64, 0x62, 0x60,

0x5e, 0x5c, 0x5a, 0x58, 0x56, 0x54, 0x52, 0x50,0x4e, 0x4c, 0x4a, 0x48, 0x46, 0x44, 0x42, 0x40,

0x3e, 0x3c, 0x3a, 0x38, 0x36, 0x34, 0x32, 0x30,0x2e, 0x2c, 0x2a, 0x28, 0x26, 0x24, 0x22, 0x20,

0x1e, 0x1c, 0x1a, 0x18, 0x16, 0x14, 0x12, 0x10,0xe, 0xc,0xa, 0x8, 0x6,0x4, 0x2, 0x00

},

{// 矩形脉冲波代码

0xff,0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,0xff, 0xff, 0xff, 0xff, 0xff, 0xff,0xff, 0xff,

0xff,0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,0xff, 0xff, 0xff, 0xff, 0xff, 0xff,0xff, 0xff,

0xff,0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,0xff, 0xff, 0xff, 0xff, 0xff, 0xff,0xff, 0xff,

0xff,0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,0xff, 0xff, 0xff, 0xff, 0xff, 0xff,0xff, 0xff,

0xff,0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,0xff, 0xff, 0xff, 0xff, 0xff, 0xff,0xff, 0xff,

0xff,0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,0xff, 0xff, 0xff, 0xff, 0xff, 0xff,0xff, 0xff,

0xff,0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,0xff, 0xff, 0xff, 0xff, 0xff, 0xff,0xff, 0xff,

0xff,0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,0xff, 0xff, 0xff, 0xff, 0xff, 0xff,0xff, 0xff,

0x00,0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,0x00, 0x00, 0x00, 0x00, 0x00, 0x00,0x00, 0x00,

0x00,0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,0x00, 0x00, 0x00, 0x00, 0x00, 0x00,0x00, 0x00,

0x00,0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,0x00, 0x00, 0x00, 0x00, 0x00, 0x00,0x00, 0x00,

0x00,0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,0x00, 0x00, 0x00, 0x00, 0x00, 0x00,0x00, 0x00,

0x00,0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,0x00, 0x00, 0x00, 0x00, 0x00, 0x00,0x00, 0x00,

0x00,0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,0x00, 0x00, 0x00, 0x00, 0x00, 0x00,0x00, 0x00,

0x00,0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,0x00, 0x00, 0x00, 0x00, 0x00, 0x00,0x00, 0x00,

0x00,0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,0x00, 0x00, 0x00, 0x00, 0x00, 0x00,0x00, 0x00,

},

{//锯齿波代码

0x00,0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,0x08,0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,

0x10,0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,0x18,0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f,

0x20,0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27,0x28,0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f,

0x30,0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37,0x38,0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f,

0x40,0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47,0x48,0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f,

0x50,0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57,0x58,0x59, 0x5a, 0x5b, 0x5c, 0x5d, 0x5e, 0x5f,

0x60,0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67,0x68,0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f,

0x70,0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77,0x78,0x79, 0x7a, 0x7b, 0x7c, 0x7d, 0x7e, 0x7f,

0x80,0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87,0x88,0x89, 0x8a, 0x8b, 0x8c, 0x8d, 0x8e, 0x8f,

0x90,0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97,0x98,0x99, 0x9a, 0x9b, 0x9c, 0x9d, 0x9e, 0x9f,

0xa0,0xa1, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7,0xa8,0xa9, 0xaa, 0xab, 0xac, 0xad, 0xae, 0xaf,

0xb0,0xb1, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6, 0xb7,0xb8,0xb9, 0xba, 0xbb, 0xbc, 0xbd, 0xbe, 0xbf,

0xc0,0xc1, 0xc2, 0xc3, 0xc4, 0xc5, 0xc6, 0xc7,0xc8,0xc9, 0xca, 0xcb, 0xcc, 0xcd, 0xce, 0xcf,

0xd0,0xd1, 0xd2, 0xd3, 0xd4, 0xd5, 0xd6, 0xd7,0xd8,0xd9, 0xda, 0xdb, 0xdc, 0xdd, 0xde, 0xdf,

0xe0,0xe1, 0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7,0xe8,0xe9, 0xea, 0xeb, 0xec, 0xed, 0xee, 0xef,

0xf0,0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7,0xf8,0xf9, 0xfa, 0xfb, 0xfc, 0xfd, 0xfe, 0xff}

};

//显示子函数

Disp7219(unsignedlong dat)

{

unsigned char i;

unsigned char led[8];

led[7]=dat%10;

led[6]=dat/10%10;

led[5]=dat/100%10;

led[4]=dat/1000%10;

led[3]=dat/10000%10;

led[2]=dat/100000%10;

led[1]=dat/1000000%10;

led[0]=dat/10000000%10;

for(i=0;i<8;i++)

{

max_7219(i+1, led[i]);

}

}

//延时约1m秒

voiddelay_ms(uint n)

{

uchar j;

while(n--)

for(j=0;j<120;j++);

}

//主函数

main()

{

unsigned int f,n,j;

delay_ms(500);

Init_Max7219();//初始化7219

Disp7219(000);

Init_Timer0();

step=18;

EA = 1;

while(1)

{

if(key0 == 0) n=n+1;

if(n==2)n=0;

if(key1==0) j=j+1;

if(j==4) j=0;

if(n==0 && j == 0 &&key2 == 0) if(step<180) step+=18; //个位增

if(n==1 && j == 0 &&key2 == 0) if(step>18) step-=18; //个位减

if(n==0 && j == 1 &&key2 == 0) if(step<1800) step+=180;//十位增

if(n==1 && j == 1 &&key2 == 0) if(step>180) step-=180; //十位减

if(n==0 && j == 2 &&key2 == 0) if(step<18000) step+=1800;//百位增

if(n==1 && j == 2 &&key2 == 0) if(step>1800) step-=1800;//百位减

if(n==0 && j == 3 &&key2 == 0) if(step<54000) step+=18000;//千位增

if(n==1 && j == 3 &&key2 == 0) if(step>18000) step-=18000;//千位减

if(key3==0)flag=flag+1;if(flag==4)flag=0;

while((!key0)||(!key1)||(!key2)||(!key3));

f=step/18;

Disp7219(f);}//显示频率

}

// 定时中断服务

voidTimer0(void) interrupt 1 using 2

{

TH0 = 0xff;

TL0 = 0x00;

counter = counter + step;

DAC=type[flag][(unsignedint)counter>>8];

}

‘叁’ 用51单片机产生方波

这个就不需要什么电路了吧，有个51最小系统板+LCD1602液晶+几个按键就OK了，因为你是输出脉冲嘛，51也就只能输出高低电平的脉冲了，外加一个液晶显示即可。你到网上查一下液晶的连接电路就OK，一大把的。

另外你说的程序也并不难啊，频率这么低，用定时计数器就可以实现了。可以做一个公式，用频率或者占空比算出具体的定时器的计数值。公式嘛，当然也是你想一下了，呵呵。

综合来看，难点就在于键盘控制而已，要读入键盘值，然后进行数据整合处理。

‘肆’ 如何用单片机产生正弦波，方波（附图，程序）

就是让某一个I/O口输出高低电平，例如让P0^0输出1HZ的方波吧，就是让它持续500ms的高电平，500ms的低电平，程序如下
#include
sbit
L1=P0^0;
void
delay1ms();
void
main()
{
LI=1;
delay1ms(500)
L1=0;
delay1ms(500);
}

‘伍’ 如何用C语言编程使单片机产生方波信号

普通51的话需要模拟PWM，如果是加强版51有内置PWM模块，

PIC和AVR以及430还有STM也有集成PWM的型号！

如果是单纯输出方波的话就简单了。

程序如下：

//功能，按下P1_0的开关降低频率，按P1_1为升高频率

#include<AT89X52.H> //引用AT89X52的库文件

#defineucharunsignedchar //替换简称

#defineuintunsignedint //替换简称

ucharsm; //定义临时变量

voiddelay_ms(uintms) //延时子函数，一个循环12uS

{

while(--ms);

}

voidT0_IRQ(void)interruptTF0_VECTOR //定时器0中断函数

{

TH0=sm; //将变量赋予定时器0的高位

P2_0=!P2_0; //翻转IO

}

//寄存器初始化子函数

voidmcu_init()

{

ET0=1; //开定时器0中断

EA=1; //开总中断

TMOD=0x01; //设置为16位定时器0

TH0=0xFF; //填充定时器高位

TR0=1; //开定时器0

sm=0xFF; //变量初始化

}

voidmain() //主函数

{

mcu_init(); //调用初始化函数

while(1) //主循环

{

if((!P1_0)||(!P1_1)) //检测是否有按键按下

{

delay_ms(8333); //延时去抖

if(!P1_0) //如果是P1_0按键按下

{

while(!P1_0); //等待按键放手

if(sm) //检测变量不为0

{

--sm; //自减1

P2_1=1; //取消边界LED

}

elseP2_1=0; //到达边界点亮LED

}

elseif(!P1_1) //否则如果P1_1按键按下

{

while(!P1_1); //等待按键放手

if(sm<0xFF) //检测变量小于0xFF

{

++sm; //自加1

P2_1=1;

}

elseP2_1=0;

}

}

}

}

‘陆’ 用单片机发生方波 程序

假设方波的周期为8微秒 如图所示 由p1.0引脚产生方波

定时时间=方波周期/2=4微秒
定时时间 t=(2的8次方-X）12/（12×1000000）=(256-x)×1微秒

X=256-4=252=0FCH 由于定时时间很短 工作在方式可以选择方式2 为8位自动重装载的
选择定时器T1定时

参考程序

ORG 0000H

LJMP MAIN

ORG 0100H

MAIN: MOV TMOD,#20H
MOV TH1,#0FCH
MOV TL1,#0FCH

SETB TR1
LL31: JNB TF1,LL31
CLR TF1
CPL P1.0
SJMP LL31

哈啊 别忘了 要为俺选择（满意回答）