单片机控制数模转换芯片DAC0832产生正弦波、方波、三角波、梯形波和锯齿波。

ID:762268 · 发表于 2020-5-27 11:12

Proteus的原理电路见图1。单片机P1.0~ P1.4接有5个按键，当按键按下时，分别对应产生正弦波、方波、三角波、梯形波和锯齿波。

单片机源程序如下:

#include<reg51.h>
sbit wr=P3^6;
sbit rd=P3^2;
sbit key0=P1^0; //定义P1.0脚的按键为正弦波键key0
sbit key1=P1^1; //定义P1.1脚的按键为方波键key1
sbit key2=P1^2; //定义P1.2脚的按键为三角波键key2
sbit key3=P1^3; //定义P1.3脚的按键为梯形波键key3
sbit key4=P1^4; //定义P1.3脚的按键为锯齿波键key4
unsigned char flag; //flag为1、2、3、4、5时对应正弦波、方波、
//三角波、梯形波、锯齿波
unsigned char const code //以下为正弦波采样点数组256个数据
SIN_code[256]={0x80,0x83,0x86,0x89,0x8c,0x8f,0x92,0x95,0x98,0x9c,0x9f,0xa2,0xa5,0xa8,
0xab,0xae,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,0xfe,0xfe,0xff,0xff,0xff,0xff,0xff,0xff,
0xff,0xff,0xff,0xff,0xff,0xfe,0xfe,0xfd,0xfc,0xfc,0xfb,0xfa,0xf9,0xf8,0xf7,0xf6,0xf5,
0xf3,0xf2,0xf0,0xef,0xed,0xec,0xea,0xe8,0xe6,0xe4,0xe3,0xe1,0xde,0xdc,0xda,0xd8,0xd6,
0xd3,0xd1,0xce,0xcc,0xc9,0xc7,0xc4,0xc1,0xbf,0xbc,0xb9,0xb6,0xb4,0xb1,0xae,0xab,0xa8,
0xa5,0xa2,0x9f,0x9c,0x99,0x96,0x92,0x8f,0x8c,0x89,0x86,0x83,0x80,0x7d,0x79,0x76,0x73,
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,
0x17,0x15,0x14,0x12,0x10,0xf,0xd,0xc,0xb,0x9,0x8,0x7,0x6,0x5,0x4,0x3,0x3,0x2,0x1,0x1,
0x0,0x0,0x0,0x0,0x0,0x0,0x0,0x0,0x0,0x0,0x0,0x1,0x1,0x2,0x3,0x3,0x4,0x5,0x6,0x7,0x8,
0x9,0xa,0xc,0xd,0xe,0x10,0x12,0x13,0x15,0x17,0x18,0x1a,0x1c,0x1e,0x20,0x23,0x25,0x27,
0x29,0x2c,0x2e,0x30,0x33,0x35,0x38,0x3b,0x3d,0x40,0x43,0x46,0x48,0x4b,0x4e,0x51,0x54,
0x57,0x5a,0x5d,0x60,0x63,0x66,0x69,0x6c,0x6f,0x73,0x76,0x79,0x7c};
unsigned char keyscan() //键盘扫描函数
{
unsigned charkeyscan_num,temp;
P1=0xff; // P1口输入
temp=P1; //从P1口读入键值，存入temp中
if(~(temp&0xff)) //判是否有键按下，即键值不为0xff，则有键按下
{ //～按位取反
if(key0==0) //产生正弦波的按键按下，P1.0=0
{
keyscan_num=1; //得到的键值为1，表示产生正弦波
}
else if(key1==0) //产生方波的按键按下，P1.1=0
{
keyscan_num=2; //得到键值为2，表示产生方波
}
elseif(key2==0) //产生三角波的按键按下， P1.2=0
{
keyscan_num=3; //得到的键值为3，表示产生三角波
}
elseif(key3==0) //产生梯形波的按键按下，P1.3=0
{
keyscan_num=4; //得到的键值为4，表示产生梯形波
}
elseif(key4==0) //产生锯齿波的按键按下， P1.3=0
{
keyscan_num=5; //得到的键值为5，表示产生锯齿波
}
else
{ keyscan_num=0; //没有按键按下，键值为0
}
returnkeyscan_num; //得到的键值返回
}
}
void init_DA0832()
{
rd=0;
wr=0;
}
void SIN()
{
unsignedint i;
i=0;
do{
P2=SIN_code[ i];
i=i+1;
}while(i<256);
}
void Square()
{
EA=1;
ET0=1;
TMOD=1;
TH0=0xff;
TL0=0x83;
TR0=1;
}
void Triangle()
{
P2=0x00;
do{
P2=P2+1;
}while(P2<0xff);
P2=0xff;
do{
P2=P2-1;
}while(P2>0x00);
P2=0x00;
}
void Sawtooth()
{
P2=0x00;
do{
P2=P2+1;
}while(P2<0xff);
}
void Trapezoidal()
{
unsignedchar i;
P2=0x00;
do{
P2=P2+1;
}while(P2<0xff);
P2=0xff;
for(i=255;i>0;i--)
{
P2=0xff;
}
do{
P2=P2-1;
}while(P2>0x00);
P2=0x00;
}
void main()
{
init_DA0832();
do
{
flag=keyscan();
}while(!flag);
while(1)
{
switch(flag)
{
case 1:
do{
flag=keyscan();
SIN();
}while(flag==1);
break;
case 2:
Square();
do{
flag=keyscan();
}while(flag==2);
TR0=0;
break;
case 3:
do{
flag=keyscan();
Triangle();
}while(flag==3);
break;
case 4:
do{
flag=keyscan();
Trapezoidal();
}while(flag==4);
break;
case 5:
do{
flag=keyscan();
Sawtooth();
}while(flag==5);
break;
default:
flag=keyscan();
break;
}
}
}
void timer0(void) interrupt 1
{
P2=~P2;
TH0=0xff;
TL0=0x83;
TR0=1;
}