用数码管与DS18B20设计温度报警器

#include

#include

#define uchar unsigned char

#define uint unsigned int

sbit DQ=P3^6;

sbit BEEP=P3^7;

sbit HI_LED=P1^4;

sbit LO_LED=P1^5;

bit HI_Alarm=0,LO_Alarm=0;

bit DS18B20_IS_OK=1;

uchar code DSY_CODE[]={0x3f,0x06,0x5b,0x4f,0x66,0x6d,0x7d,0x07,0x7f,0x6f,0x00}; //数码管共阴极段码

uchar code df_Table[]={0,1,1,2,3,3,4,4,5,6,6,7,8,8,9,9}; //温度小数位对照表uchar CurrentT=0; //温度整数部分

uchar Display_Digit[]={0,0,0,0}; //数码管待显示的各位温度

uchar Temp_Value[]={0x00,0x00}; //DS0832读取的温度值

uint Time0_Count=0; // 定时器中断计数

char Alarm_Temp_HL[2]={70,-20};

/***********延时程序*************/

void Delay(uint x)

{

while(--x);

}

/**********DS18B20初始化********/

uchar Init_DS18B20()

{

uchar status;

DQ=1;Delay(8);

DQ=0;Delay(90);

DQ=1;Delay(8);

status=DQ;

Delay(100);

DQ=1;

return status;

}

/**********DS18B20读字节********/

uchar ReadOneByte()

{

uchar i,dat=0;

DQ=1;_nop_();

for(i=0;i<8;i++)

DQ=0;dat >>=1;DQ=1;_nop_();_nop_();

if (DQ) dat |=0x80; Delay(30); DQ=1;

}

return dat;

}

/**********DS18B20写字节********/

void WriteOneByte(uchar dat)

{

uchar i;

for(i=0;i<8;i++)

{

DQ=0;DQ=dat & 0x01;Delay(5); DQ=1; dat>>=1;

}

}

/**********从DS18B20读取温度********/

void Read_Temperature()

{

if( Init_DS18B20()==1)

DS18B20_IS_OK=0;

else

{

WriteOneByte(0xCC);

WriteOneByte(0x44);

Init_DS18B20();

WriteOneByte(0xCC);

WriteOneByte(0xBE);

Temp_Value[0]=ReadOneByte();

Temp_Value[1]=ReadOneByte();

DS18B20_IS_OK=1;

}

}

/**********给DS18B20设置报警值********/

void Set_Alarm_Temp_Value()

{

Init_DS18B20();

WriteOneByte(0xcc); //跳过序列号

WriteOneByte(0x4e); //将设定的温度报警值写入DS18B20 WriteOneByte(Alarm_Temp_HL[0]); //写TH

WriteOneByte(Alarm_Temp_HL[1]); //写TL

WriteOneByte(0x7f); //12位精度

Init_DS18B20();

WriteOneByte(0xcc); //跳过序列号

WriteOneByte(0x48); //将温度报警值存入DS18B20

/**********温度值显示******************/

void Display_Temperature() //显示温度

{

uchar i;

uchar t=150; //延时值

uchar ng=0,np=0; //负数标示，及负号显示位置

char Signed_Current_Temp;

if((Temp_Value[1]&0xf8)==0xf8) //如果为负数，取反加1；设置负数标示及负号显示位置

{

Temp_Value[1]=~Temp_Value[1];

Temp_Value[0]=~Temp_Value[0]+1;

if(Temp_Value[0]==0x00)Temp_Value[1]++;

ng=1;np=0xfd;

}

Display_Digit[0]=df_Table[Temp_Value[0]&0x0f]; //查表显示温度小数位

CurrentT=((Temp_Value[0]&0xf0)>>4)|((Temp_Value[1]&0x07)<<4);

Signed_Current_Temp=ng? -CurrentT : CurrentT;

HI_Alarm= Signed_Current_Temp >= Alarm_Temp_HL[0] ? 1:0;

LO_Alarm= Signed_Current_Temp <= Alarm_Temp_HL[1] ? 1:0;

Display_Digit[3]=CurrentT/100;

Display_Digit[2]=CurrentT%100/10;

Display_Digit[1]=CurrentT%10;

if(Display_Digit[3]==0) //高位为0，不现实，负号后移

{ Display_Digit[3]=10;

np=0xfb;

if(Display_Digit[2]==0)

{

Display_Digit[2]=10;

np=0xf7;

}

}

for(i=0;i<30;i++) //刷新数码管显示温度值

{

P0=0X39;P2=0X7F;Delay(t);P2=0XFF;

P0=0X63;P2=0XBF;Delay(t);P2=0XFF;

P0=DSY_CODE[Display_Digit[0]];

P2=0XDF;Delay(t);P2=0XFF;

P0=(DSY_CODE[Display_Digit[1]])|0X80;

P2=0XEF;Delay(t);P2=0XFF;

P0=DSY_CODE[Display_Digit[2]];

P2=0XF7;Delay(t);P2=0XFF;

P0=DSY_CODE[Display_Digit[3]];

P2=0XFB;Delay(t);P2=0XFF;

if(ng)

{P0=0X40;P2=np;Delay(t);P2=0XFF;}

}

}

/**********定时器0中断，控制报警声音********/ void T0_INT()interrupt 1

{

TH0=-1000/256;

TL0=-1000%256;

BEEP=!BEEP;

if(++Time0_Count==400)

{

Time0_Count=0;

if(HI_Alarm)HI_LED=~HI_LED;

else HI_LED=1;

if(LO_Alarm)LO_LED=~LO_LED;

else LO_LED=1;

}

}

void main()

{

IE=0X82;

TMOD=0X01; //方式1计数

TH0=-1000/256;

TL0=-1000%256;

TR0=0;

HI_LED=1;

LO_LED=1;

Set_Alarm_Temp_Value();

Read_Temperature();

Delay(50000); Delay(50000);

while(1)

{

Read_Temperature();

if(DS18B20_IS_OK)

{

if(HI_Alarm==1||LO_Alarm==1)TR0=1;

else TR0=0;

Display_Temperature();

}

else{P0=P2=0X00;}

}

}