#include <at89x51.h>
#define uchar unsigned char
#define uint unsigned int
#define uchar unsigned char
#define uint unsigned int
unsigned char i;
sbit DQ=P3^0;//ds18b20與單片機(jī)連接口
uchar disdata[5];
idata uint tvalue;//溫度值
idata uchar tflag;//溫度正負(fù)標(biāo)志    

sbit rs=P3^2;
sbit rw=P3^3;
sbit en=P3^4;
sbit key_left=P1^0;
sbit key_right=P1^1;


uchar code opens[]="MACROSS";
uchar code opens1[]="FRONTIER";
uchar code hanzi[3][8]={0x1f,0x11,0x11,0x1f,0x11,0x11,0x1f,0x00,
					   0x0f,0x09,0x0f,0x09,0x0f,0x09,0x11,0x00,
					   0x08,0x0f,0x12,0x0f,0x0a,0x1f,0x02,0x02};
void open();
void ini(); 
void write_order(uchar order);
void write_date(uchar date);
void delay(uchar z);
void writeCG();
/******************************ds1820程序***************************************/

void ini()
{
	rw=0;
	en=0;
	P1=0xff;
	writeCG();
	write_order(0x38);
	write_order(0x0c);
	write_order(0x06);
	write_order(0x01);
	

}
void write_order(uchar order)
{
	rs=0;
	P2=order;
	delay(4);
	en=1;
	delay(4);
	en=0;
}
void write_date(uchar date)
{	
	rs=1;
	P2=date;
	delay(4);
	en=1;
	delay(4);
	en=0;
}
void delay(uchar z)
{
	uchar x,y;
	for(x=z;x>0;x--)
		for(y=110;y>0;y--);
}
void writeCG()
{
	uchar x,y;
	write_order(0x40);
	for(y=0;y<3;y++)
	{
		for(x=0;x<8;x++)
		{
			write_date(hanzi[y][x]);
		}
	}
	
}
void open()
{
	uchar num;
	write_order(0x80+0x10);
	for(num=0;opens[num]!='\0';num++)
	{
		write_date(opens[num]);
		delay(20);
	}

	
			for(num=0;num<16;num++)
	{
		write_order(0x1c);
		delay(200);
	}
			for(num=0;num<5;num++)
	{
		write_order(0x18);
		delay(200);
	}
			for(num=0;num<4;num++)
	{
		write_order(0x1c);
		delay(200);
	}
			for(num=0;num<3;num++)
	{
		write_order(0x18);
		delay(200);
	}
			for(num=0;num<2;num++)
	{
		write_order(0x1c);
		delay(200);
	}
			for(num=0;num<1;num++)
	{
		write_order(0x18);
		delay(100);
	}
	write_order(0x80+0x53);
	for(num=0;opens1[num]!='\0';num++)
	{
		write_date(opens1[num]);
		delay(500);
	}
}


void delay_18B20(unsigned int t)//延時(shí)1微秒
{
   while(t--);
}

void ds1820rst()/*ds1820復(fù)位*/
{ 
    unsigned char x=0;
    DQ = 1;          //DQ復(fù)位
    delay_18B20(4); //延時(shí)
    DQ = 0;          //DQ拉低
    delay_18B20(100); //精確延時(shí)大于480us
    DQ = 1;          //拉高
    delay_18B20(40); 
} 

uchar ds1820rd()/*讀數(shù)據(jù)*///讀時(shí)間隙
{
    unsigned char j=0;
    unsigned char dat = 0;
    for (j=8;j>0;j--)
    {   
	    DQ = 0; //給脈沖信號(hào)
        dat>>=1;
        DQ = 1; //給脈沖信號(hào)
        if(DQ)
        dat|=0x80;
        delay_18B20(10);
    }
    return(dat);
}

void ds1820wr(uchar wdata)/*寫數(shù)據(jù)*/
{
    unsigned char j=0;
    for (j=8; i>0; j--)
    {
        DQ = 0;
        DQ = wdata&0x01;
        delay_18B20(10);
        DQ = 1;
        wdata>>=1;
    }
}

read_temp()/*讀取溫度值并轉(zhuǎn)換*/
{
    uchar a,b;
    ds1820rst();    
    ds1820wr(0xcc);//*跳過讀序列號(hào)*/
    ds1820wr(0x44);//*啟動(dòng)溫度轉(zhuǎn)換*/
    ds1820rst();    
    ds1820wr(0xcc);//*跳過讀序列號(hào)*/  
    ds1820wr(0xbe);//*讀取溫度*/  
    a=ds1820rd();
    b=ds1820rd();
    tvalue=b;
    tvalue<<=8;
    tvalue=tvalue|a;
    if(tvalue<0x0fff)
        tflag=0;
    else
    {
	    tvalue=~tvalue+1;
        tflag=1;
    }
    tvalue=tvalue*(0.625);//溫度值擴(kuò)大10倍，精確到1位小數(shù)
    return(tvalue);
}
/*******************************************************************/
void ds1820disp()//溫度值顯示
{ 
    uchar flagdat;
    disdata[0]=tvalue/1000+0x30;//百位數(shù)
    disdata[1]=tvalue%1000/100+0x30;//十位數(shù)
    disdata[2]=tvalue%100/10+0x30;//個(gè)位數(shù)
    disdata[3]=tvalue%10+0x30;//小數(shù)位
    
    if(tflag==0)
        flagdat=0x20;//正溫度不顯示符號(hào)
    else
       flagdat=0x2d;//負(fù)溫度顯示負(fù)號(hào):-
    if(disdata[0]==0x30)
    {
	    disdata[0]=0x20;//如果百位為0，不顯示     
        if(disdata[1]==0x30)
        {
	        disdata[1]=0x20;//如果百位為0，十位為0也不顯示
        }
    }
    write_order(0xc0);
    write_date(flagdat);//顯示符號(hào)位
    write_order(0xc1);
    write_date(disdata[0]);//顯示百位
    write_order(0xc2);
    write_date(disdata[1]);//顯示十位 
    write_order(0xc3);
    write_date(disdata[2]);//顯示個(gè)位 
    write_order(0xc4);
    write_date(0x2e);//顯示小數(shù)點(diǎn)    
    write_order(0xc5);
    write_date(disdata[3]);//顯示小數(shù)位  
   }
/********************主程序***********************************/
void main()
{ 

    while(1) 
    {
	    read_temp();//讀取溫度   
        ds1820disp();//顯示    
    }
}