adc.c

一个简单的数模转换程序

#include<reg51.h>
#define uchar unsigned char
sbit start=P3^2;
sbit oe=P3^0;
sbit  jieshu=P3^1;

sbit P20=P2^0; //显示位
sbit P21=P2^1;
sbit P22=P2^2;
sbit P23=P2^3;

sbit a=P3^4; //channel
sbit b=P3^5;
sbit c=P3^6;

sbit speak=P2^5;
sbit  shang=P2^6;
sbit   xia=P2^7;

uchar code  duan[]={0x3f,0x06,0x5B,0x4F,0x66,0x6D,0x7D,0x07,0x7F,0x6f};

void delay_20us(uchar a)
{  uchar time0,i;
for (i=0;i<a;i++)
{
 for (time0=0;time0<10;time0++) ;}
}


 void channel3()
 {a=1;b=1;c=0;}

 void st()
 { start=0;
   start=1;
   start=0;
   }

void led(int n)    //数码管显示及数据处理程序 
{  if(n>200){speak=0;delay_20us(5);speak=1;delay_20us(3);shang=0;}
    else {speak=1;shang=1;}
   if(n<50){ speak=0;delay_20us(5);speak=1;delay_20us(3);xia=0;	}
     else {speak=1;xia=1;}
   P0 = 0x00; 
P0=duan[n % 10];  //个位 
   P23 = 0; 
 delay_20us(5); 
   P23 = 1; 

   P0 = 0x00; 
P0=duan[n / 10 % 10];  //十位 
   P22 = 0; 
  delay_20us(5);
   P22 = 1; 

  P0 = 0x00; 
P0 =duan[n / 100 % 10];   //百位 
   P21 = 0; 
 delay_20us(5); 
   P21 = 1; 

   P0 = 0x00; 
   P0 = duan[n / 1000 % 10];   //千位 
   P20 = 0; 
  delay_20us(5); 
   P20 = 1;   
} 

void main()
{int  value;

	while(1)
	{
    channel3();
	st();
	do{}while (jieshu==0);
	oe=1;
    value=P1;
	oe=0;
	led(value);
	}
}