单片机光敏电阻源码

光敏电阻，经过PCF8591进行AD转换（采用I2C总线）， 数码管前3位显示温度， 定时器1进行定时和I2C总线通信。
 #include<reg52.h> 
 #define uchar unsigned char
 sbit sda=P2^0;
 sbit scl=P2^1;    
 sbit dula=P2^6;
 sbit wela=P2^7;
 sbit rst=P2^4;
 uchar c;
 uchar a[3];
 bit ADflag;
 uchar code table[]=
{
0x3f,0x06,0x5b,0x4f,
0x66,0x6d,0x7d,0x07,
0x7f,0x6f,0x77,0x7c,
0x39,0x5e,0x79,0x71,
0x80,//最后为小数点
};
void init();
void start();
void stop();
void response();
uchar read_byte();
void write_byte(uchar data1);
uchar ADC(uchar ch);
void display();
void delay_100(int z)  ;
void main()
 {

  uchar data2;
rst=0;
init();
P1=0xff;
while(1)
{
if(ADflag)//ADflag由定时器1控制
{


ADflag=0;
data2=ADC(0);  
if(data2>100)P1=0x00;//假如光线太暗，则点亮二极管。
else P1=0xff;
a[0]=data2/100;
a[1]=data2%100/10;
a[2]=data2%10;
display();
}
}  
 }
 void init()
 {
  TMOD=0x10;
TH1=(65535-500)/256;
TL1=(65535-500)%256;
EA=1;
TR1=1;
ET1=1;
 }