#include <reg52.h>

//宏定义
sbit RS = P3^5;
sbit RW = P3^6;
sbit EN = P3^4;
sbit DQ = P2^2;
unsigned int shuju;
unsigned char a;
unsigned char b;
unsigned char c;

unsigned char code digital[] = {0x30,0x31,0x32,0x33,0x34,0x35,0x36,0x37,0x38,0x39};

//延时函数
void yanchi_1602(unsigned char q)
{
	unsigned char p;
	while(q--)
	{
		for(p=0;p<=113;p++);
	}
}
//
void Delay(int n)
{
	while(n--);
}

//发送命令
void Wcmd(unsigned char cmd)
{
	RS = 0;
	RW = 0;
	EN = 1;
	P0 = cmd;
	yanchi_1602(5);
	EN = 0;
}

//发送数据
void Wdat(unsigned char dat)
{
	RS = 1;
	RW = 0;
	EN = 1;
	P0 = dat;
	yanchi_1602(5);
	EN = 0;
}

//初始化1602屏幕
void start_1602()
{
	Wcmd(0x01); //清屏
	Wcmd(0x02); //光标归位
	Wcmd(0x06); //设置输入模式
	Wcmd(0x0C); //显示设置
	Wcmd(0x38); //功能设置
}
//
void plan()
{
	a = shuju/100;
	b = shuju%100/10;
	c = shuju%10;
}



//B站
//初始化DS18B20
void Init_18b20()
{
	DQ = 1;      //DQ复位
	Delay(4);    //延时
	DQ = 0;      //DQ拉低
	Delay(100);  //精确延时大于48us
	DQ = 1;      //DQ拉高
	Delay(40);   //延时
}
//读数据函数
unsigned char Readdat()
{
	unsigned char i = 0;
	unsigned char dat = 0;
	for(i=8;i>0;i--)
	{
		DQ = 1;
		Delay(1);
		
		DQ = 0;
		dat >>= 1;
		DQ = 1;
		if(DQ)
			dat |= 0x80;
		Delay(10);
	}
	return(dat);
}
//写数据函数
void Writedat(unsigned char dat)
{
	unsigned char i = 0;
	for(i=8;i>0;i--)
	{
		DQ = 0;
		DQ = dat & 0x01;
		Delay(10);
		DQ = 1;
		dat >>= 1;
	}
}
//读取温度
unsigned int ReadDigital(void)
{
	unsigned char m;
	unsigned char n;
	
	Init_18b20();
	Writedat(0xcc);  //跳过读序列号
	Writedat(0x44);  //启动温度转换
	Delay(5);
	Init_18b20();
	Writedat(0xcc);  //跳过读序列号
	Writedat(0xbe);  //开始读取温度
	m = Readdat();
	n = Readdat();
	
	shuju = n;
	shuju <<= 8;
	shuju = shuju|m;
	shuju = (shuju*0.0625)*10;   //温度值扩大十倍，精确到一位小数
	
	return(shuju);
}

void main()
{
	start_1602();
	
	Wcmd(0x82);
	Wdat('t');
	
	Wcmd(0x83);
	Wdat('e');
	
	Wcmd(0x84);
	Wdat('m');
	
	Wcmd(0x85);
	Wdat('p');
	
	Wcmd(0x86);
	Wdat('e');
	
	Wcmd(0x87);
	Wdat('r');
	
	Wcmd(0x88);
	Wdat('a');
	
	Wcmd(0x89);
	Wdat('t');
	
	Wcmd(0x8a);
	Wdat('u');
	
	Wcmd(0x8b);
	Wdat('r');
	
	Wcmd(0x8c);
	Wdat('e');
	
	Wcmd(0x8d);
	Wdat(':');
	
	while(1)
	{
		shuju = ReadDigital();
		plan();
		
		Wcmd(0xc4);
		Wdat('+');
		
		Wcmd(0xc5);
		Wdat(digital[a]);
		
		Wcmd(0xc6);
		Wdat(digital[b]);
		
		Wcmd(0xc7);
		Wdat('.');
		
		Wcmd(0xc8);
		Wdat(digital[c]);
	}
}