ds18b20.c

温度检测SDFFSDTGDFHRTUJTYJUTYJTY

#include<AT89X52.H>
#include<INTRINS.H>
unsigned char code displaybit_p[]={0xf1,0xf2,0xf4,0xf8};	 //正温度位选
//unsigned char code displaybit_close={0xf0
unsigned char code displaybit_n[]={0xd1,0xd2,0xd4,0xd8};	 //负温度位选
unsigned char code displaycode[]={0xc0,0xf9,0xa4,0xb0,
                                     0x99,0x92,0x82,0xf8,
									 0x80,0x90,0x88,0x83,
									 0xc6,0xa1,0x86,0x8e,0xff,0xbf};
unsigned char dotcode[32]={0,3,6,9,12,16,19,22,
							 25,28,31,34,38,41,44,48,
							 50,53,56,59,63,66,69,72,
							 75,78,81,84,88,91,94,97};
unsigned char displaycount;
unsigned char read_sign;
unsigned displaybuf[4]={16,16,16,16};
unsigned displaybuf_1[4]={16,16,16,16};
unsigned char timecount;
unsigned char readdata[8];
sbit DQ=P3^7;
bit sflag;

 void show(void)
 {
  if(displaycount==2)
    {
     P1=displaycode[displaybuf[displaycount]]&0x7f;
     }
     else
     {
     P1=displaycode[displaybuf[displaycount]];
     }
	if(sflag==0	)
    P2=displaybit_p[displaycount];
	else
	 P2=displaybit_n[displaycount];
   displaycount++;
   if(displaycount==4)
   {
    displaycount=0;		
   }
 } 
//复位处理
bit resetpulse(void)
{
 unsigned char i;
 DQ=0;
 for(i=255;i>0;i--);
 DQ=1;
 for(i=60;i>0;i--);
 return(DQ)	;
 for(i=200;i>0;i--);
 show();
}
//写数据到DS18B20
void  writecommandtods18b20(unsigned char command)
{
 unsigned char i;
 unsigned char j;
 for(i=0;i<8;i++)
 {
   if((command&0x01)==0)
   {
    DQ=0;
	for(j=35;j>0;j--);
	DQ=1;
    }
	else
	{
	 DQ=0;
	 for(j=2;j>0;j--);
	 DQ=1;
	 for(j=33;j>0;j--);

	}
	command=_cror_(command,1);
	show();

 }

}

//主机读数据
unsigned char readdatafromds18b20(void)
{
   unsigned char i;
   unsigned char j;
   unsigned char temp;
   temp=0;
   for(i=0;i<8;i++)
   {
    temp=_cror_(temp,1);
	DQ=0;
	_nop_();
	_nop_();
	DQ=1;
    for(j=10;j>0;j--);
	if(DQ==1)
	{
	 temp=temp|0x80;
	 }
	 else
	 {
	  temp=temp|0x00;
	 }
	 for(j=200;j>0;j--);
	 show();
   }
   return(temp);
}
void main(void)
{
 unsigned  int i;
 TMOD=0x01;
 TH0=(65536-4000)/256;
 TL0=(65536-4000)%256;
 ET0=1;
 EA=1;
 while(resetpulse());
 writecommandtods18b20(0xcc);
 writecommandtods18b20(0x44);
 TR0=1;
 while(1)
 {
 
   i++;
   if(i==100)    
   {
  // show();
   i=0;
   }
   

 }
 }
void t0(void)  interrupt 1
{
 unsigned char x;
 unsigned int result;
 TH0=(65536-4000)/256;
 TL0=(65536-4000)%256;
   
    if(displaycount==2)
    {
     P1=displaycode[displaybuf[displaycount]]&0x7f;
     }
     else
     {
     P1=displaycode[displaybuf[displaycount]];
     }
	if(sflag==0	)
    P2=displaybit_p[displaycount];
	else
	 P2=displaybit_n[displaycount];
   displaycount++;
   if(displaycount==4)
   {
    displaycount=0;		   
	}
   
  timecount++;
 if(timecount==188)
  {
 
    TR0=0;
    timecount=0;
    while(resetpulse());
	show();
	writecommandtods18b20(0xcc);
	show();
	writecommandtods18b20(0xbe);
	show();
	readdata[0]=readdatafromds18b20();
	show();
    readdata[1]=readdatafromds18b20();
	show();

	for(x=0;x<4;x++)
	{
	 displaybuf[x]=16;

	}
	sflag=0;
	if((readdata[1]&0xf8)!=0x00)
	{
	 sflag=1;
	 readdata[1]=~readdata[1];
	 readdata[0]=~readdata[0];
	 result=readdata[0]+1;
	 readdata[0]=result;
	 if(result>255)
	 {
	  readdata[1]++;

	 }
	}
	readdata[1]=readdata[1]<<4;
	readdata[1]=readdata[1]&0x70;
	x=readdata[0];
	x=x>>4;
	x=x&0x0f;
	readdata[1]=readdata[1]|x;
	x=2;
	result=readdata[1];
	while(result/10)
	{
	 displaybuf[x]=result%10;
	 result=result/10;
	 x++;
	 }
	 displaybuf[x]=result;
	 x=readdata[0]&0x0f;
	 x=x<<1;
	 displaybuf[0]=(dotcode[x])%10;
	 displaybuf[1]=(dotcode[x]/10);
	show();
	 while(resetpulse());
	writecommandtods18b20(0xcc);
	show();
	writecommandtods18b20(0x44);
	show();
	TR0=1;
   
  }

}