温度传感器

#include <AT89X52.H>
#include <INTRINS.H>

unsigned char code displaybit[]={0xfe,0xfd,0xfb,0xf7,
0xef,0xdf,0xbf,0x7f};
unsigned char code displaycode[]={0x3f,0x06,0x5b,0x4f,
0x66,0x6d,0x7d,0x07,
0x7f,0x6f,0x77,0x7c,
0x39,0x5e,0x79,0x71,0x00};

unsigned char code 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};


sbit SDA=P1^6;
sbit SCL=P1^7;

unsigned char displaybuffer[8]={0,1,2,3,4,5,6,7};
unsigned char eepromdata[8];
unsigned char temperdata[2];

unsigned char timecount;
unsigned char displaycount;

bit secondflag=0;
unsigned char secondcount=0;
unsigned char retn;
unsigned int result;
unsigned char x;
unsigned int k;
unsigned int ks;



void delay(void);
void delay10ms(void);
void i_start(void);
void i_stop(void);
void i_init(void);
void i_ack(void);
bit i_clock(void);
bit i_send(unsigned char i_data);
unsigned char i_receive(void);

bit start_temperature_T(void);
bit read_temperature_T(unsigned char *p);

void delay(void)
{
_nop_();
_nop_();
_nop_();
_nop_();
_nop_();
_nop_();
}

void delay10ms(void)
{
unsigned int i;
for(i=0;i<1000;i++)
{
delay();
}

}

void i_start(void)
{
SCL=1;
delay();
SDA=0;
delay();
SCL=0;
delay();
}

void i_stop(void)
{
SDA=0;
delay();
SCL=1;
delay();
SDA=1;
delay();
SCL=0;
delay();
}

void i_init(void)
{
SCL=0;
i_stop();
}

void i_ack(void)
{
SDA=0;
i_clock();
SDA=1;
}

bit i_clock(void)
{
bit sample;

SCL=1;
delay();
sample=SDA;
_nop_();
_nop_();
SCL=0;
delay();
return(sample);
}


bit i_send(unsigned char i_data)
{
unsigned char i;

for(i=0;i<8;i++)
{
SDA=(bit)(i_data & 0x80);
i_data=i_data<<1;
i_clock();
}
SDA=1;
return(~i_clock());
}

unsigned char i_receive(void)
{
unsigned char i_data=0;
unsigned char i;

for(i=0;i<8;i++)
{
i_data*=2;
if(i_clock()) i_data++;
}
return(i_data);
}

bit start_temperature_T(void)
{
i_start();
if(i_send(0x90))
{
if(i_send(0xee))
{
i_stop();
delay();
return(1);
}
else
{
i_stop();
delay();
return(0);
}
}
else
{
i_stop();
delay();
return(0);
}
}

bit read_temperature_T(unsigned char *p)
{
i_start();
if(i_send(0x90))
{
if(i_send(0xaa))
{
i_start();
if(i_send(0x91))
{
*(p+1)=i_receive();
i_ack();
*p=i_receive();
i_stop();
delay();
return(1);
}
else
{
i_stop();
delay();
return(0);
}
}
else
{
i_stop();
delay();
return(0);
}
}
else
{
i_stop();
delay();
return(0);
}
}


void main(void)
{
P1=0xff;
timecount=0;
displaycount=0;

TMOD=0x21;
TH1=0x06;
TL1=0x06;
TR1=1;
ET1=1;
ET0=1;
EA=1;


if(start_temperature_T()) //向DS1624发送启动A/D温度转换命令，成功则启动T0定时1s。
{
secondflag=0;
secondcount=0;
TH0=55536/256;
TL0=55536%256;
TR0=1;
}

while(1)
{
if(secondflag==1)
{
secondflag=0;
TR0=0;
if(read_temperature_T(temperdata)) //T0定时1s时间到，读取DS1624的温度值
{
for(x=0;x<8;x++)
{
displaybuffer[x]=16;
}
x=2;
result=temperdata[1]; //将读取的温度值进行数据处理，并送到显示缓冲区
while(result/10)
{
displaybuffer[x]=result%10;
result=result/10;
x++;
}
displaybuffer[x]=result;
result=temperdata[0];
result=result>>3;
displaybuffer[0]=(dotcode[result])%10;
displaybuffer[1]=(dotcode[result])/10;
if(start_temperature_T()) //温度值数据处理完毕，重新启动DS1624开始温度转换
{
secondflag=0;
secondcount=0;
TH0=55536/256;
TL0=55536%256;
TR0=1;
}
}
}
}
}


void t0(void) interrupt 1 using 0 //T0用于定时1s时间到
{
secondcount++;
if(secondcount==100)
{
secondcount=0;
secondflag=1;
}
TH0=55536/256;
TL0=55536%256;
}


void t1(void) interrupt 3 using 0 //T1定时1ms用数码管的动态刷新
{
timecount++;
if(timecount==4) //T1定时1ms到
{
timecount=0;
if (displaycount==5)
{
P0=(displaycode[displaybuffer[7-displaycount]] | 0x80); //在该位同时还要显示小数点
}
else
{
P0=displaycode[displaybuffer[7-displaycount]];
}
P2=displaybit[displaycount];
displaycount++;
if(displaycount==8)
{
displaycount=0;
}
}
}