ADC0809模数转换

目标

将模拟电压通过AD转换，通过AT89C51单片机接数码管显示转换结果。

代码

ADC0809的芯片介绍：ADC0809的芯片简介

#include "reg52.h"			
char code ShuMaGuan[16]={0x3f,0x06,0x5b,0x4f,0x66,0x6d,0x7d,0x07,
                     0x7f,0x6f,0x77,0x7c,0x39,0x5e,0x79,0x71};	 //共阴
#define led P0	  //P1端口控制数码管段选端
#define wei P2	  //P3端口控制位选端
#define Vref 5.0

sbit ALE=P3^0;
sbit ST=P3^1;
sbit EOC=P3^2;
sbit OE=P3^3;

int Volt1[3]={0,0,0};	 //将各位数值存储
long double Data1=0;	//数码管通道0电压值

void delay(int i)
{  while(i--);}	//延时

void Display()
{
	char i;
	//存放Data1值:
	Volt1[2]=(int)(Data1*100)%10;
	Volt1[1]=(int)(Data1*10)%10;	  
	Volt1[0]=(int)Data1%10;		
	//送显Data1
	for(i=0;i<3;i++)
	{
    wei=(0x01<<i); 
	if(i==0)
	  led=~ShuMaGuan[Volt1[i]]+0x80;	 //加小数点
	else
	  led=~ShuMaGuan[Volt1[i]];
	delay(1000);
	led=~0x00;			  //消隐  
	}				
}

void main()
{	
	ALE=1;
	while(1)
	{  
		//读取通道0的电压值:
		float n=0;
		ST=0;
		ST=1;
		ALE=1;
		ST=0;
		while(!EOC);
		OE=1;	
		n=P1;
		Data1=Vref*n/255;	 //AD转换 

		Display(); 			 
	}		
}

仿真机结果