#define uchar unsigned char
#define uint  unsigned int

#include "reg52.h"
#include "intrins.h"

sbit ADCS =P2^3;
sbit ADCLK=P2^2;
sbit ADDO =P2^1;
//sbit ADDI =P2^0;

uchar ADConv()
{
   uchar i,ch=0;

   ADCS = 0;
   ADCLK = 0;
   _nop_();
   _nop_();
   ADCLK = 1;
   _nop_();
   _nop_();
   ADCLK = 0;
   _nop_();
   _nop_();
   _nop_();
   _nop_();

   //AD轉(zhuǎn)換開始
   for (i=0; i<8; i++)
     { 
        ADCLK=1;//時鐘脈沖啟動
        _nop_();
        _nop_();
        ADCLK=0;//時鐘下降沿講讀數(shù) 
        _nop_();
        _nop_();
        ch=(ch<<1)|ADDO;//在每個脈沖的下降沿DO輸出一位數(shù)據(jù)，最終ch為8位二進制數(shù)
    }
  
    ADCS = 1;//轉(zhuǎn)換結(jié)束

return(ch);

}