单片机控制的温度传感器C语言程序

1、#include <at89x52.h>#define DO P3_7 #define SEG P0 /数码管自左至右依次为1234位#define MS2L 0x18 /1ms的延时参数#define MS2H 0xfc#define uchar unsigned char#define uint unsigned intuchar code comm4 = 0x01,0x02,0x04,0x08;uchar code seg10 = 0xc0,0xf9,0xa4,0xb0,0x99,0x92,0x82,0xf8,0x80,0x90;uchar code seg_add_dici

2、mal10 = 0x40,0x79,0x24,0x30,0x19,0x12,0x02,0x78,0x00,0x10; uchar code seg_dicimal2 =0xc0, 0x92;uchar k = 0;uchar temp_l = 0;uchar temp_h = 0;uchar tempsign = 0;uchar hundreds = 0;uchar tens = 0;uchar ones = 0;uchar low_four = 0;/*延时以ms为单位的t时间*/void Delay(uint t) uint i; while(t-) for(i=0; i<125;

3、i+) /*us级延时,延时时间约42*i*/void Delayus(uchar i) while(-i); /*产生复位脉冲,等待应答信号*/void Resetpaulse() DO = 0; /拉低约600us Delayus(150); Delayus(150); DO = 1;/产生上升沿,延时约1560us Delayus(30); while(DO); /等待应答信号 /*读取数据一位*/bit Readbit() uint i = 0; bit b = 0; DO = 0; /产生读时隙 i+; /维持低电平至少1us DO = 1; /1us以上后拉高 Delayus(2)

4、; /延时8us，DO下降沿15内ds18b20输出的数据才有效 b = DO; /读取数据 Delayus(40); /每个读时隙至少持续60us return(b); /*读取一个字节*/uchar Readbyte() uchar byte_read = 0; uchar i, j; for(i=0; i<8; i+) j = Readbit(); byte_read = (j<<i) | byte_read; /低位读起 return(byte_read); /*写一个字节*/void Writebyte(uchar byte_to_write) uchar i =

5、0; uchar j = 0; bit write_bit = 0; for(j=0; j<8; j+) write_bit = (byte_to_write & 0x01); if(write_bit = 1) /写1 DO = 0; /产生写时隙 Delayus(3); /延时15us DO = 1; /写1 Delayus(40); /延时，写时隙不得低于60us else DO = 0; /产生写时隙 Delayus(50); /延时，保持低约60us120us DO = 1; i+; byte_to_write = byte_to_write >> 1; /

6、*配置ds18b20，9位分辨率 */void Configurate() EA = 0; Resetpaulse(); /发出复位脉冲，每次操作都从复位开始 Delay(1); Writebyte(0xcc); /skip room命令 Writebyte(0x4e); Writebyte(0x7f); Writebyte(0x80); Writebyte(0x1f); EA = 1;/*启动温度转换*/void StartConvert() Resetpaulse(); / 发出复位脉冲，每次操作都从复位开始 Delay(1); EA = 0; Writebyte(0xcc); /skip

7、 room命令 Writebyte(0x44); /启动温度转换命令 EA = 1;/*读取温度值*/void ReadTempreture() EA = 0; Resetpaulse(); / 发出复位脉冲，每次操作都从复位开始 Delay(1); Writebyte(0xcc); /skip room命令 Writebyte(0xbe); /读取暂存器命令 temp_l = Readbyte(); /存储温度低字节值 （整数部分低四位和小数部分） temp_h= Readbyte(); /存储温度高字节值 （其中高五位为符号位） EA = 1;/*数据转换*/void DigitalCon

8、vert() uchar total = 0; tempsign = (temp_h >> 7) & 0x01; /得出符号位 if(tempsign = 0) /正数的处理方法 total = (temp_h << 4)&0xf0) | (temp_l >> 4)&0x0f); /取整数位 low_four = (temp_l>>3) & 0x01; /取小数位，9位分辨率，低字节第3位为小数位，只有0、1两种取值 hundreds = total / 100; /计算百、十、个位 tens = (total%1

9、00)/10; ones = (total%100)%10; else /负数处理 求负数补码规则是，按位取反，得到反码，加1即得补码（符号位不变） tempsign = 1; total = (temp_l >> 4) & 0x0f); /取整数部分低4位 total |= (temp_h << 4) & 0xf0); /整数部分高三位和符号位 low_four = (temp_l >> 3) & 0x01; /取小数位 if(low_four = 0) /这里total位uchar型变量，所以根据最低位来确定整数取补规则 tota

10、l = total + 1; /最低位为0的时候，取反加1后有进位，所以这里total要取反加1 else total = total;/最低位为1的时候，取反加1没有进位，所以total直接取反即可 tens = (total%100)/10; ones = (total%100)%10; /*中断处理*/void Display()interrupt 1 EA = 0; TL0 = MS2L; TH0 = MS2H; DigitalConvert(); /数据转换 if(tempsign = 0)/正数 if(k = 0) if(hundreds = 0) /高位0消隐 P1 = 0; e

11、lse P1 = commk; SEG = seghundreds; else if(k = 1) if(tens = 0 && hundreds = 0) /高位0消隐 P1 = 0; else P1 = commk; SEG = segtens; else if(k = 2)/显示个位，因为个位有小数点，所以又定义了一个数组分开来显示 P1 = commk; SEG = seg_add_dicimalones; /要加上小数点else /显示小数，0或5 P1 = commk; SEG = seg_dicimallow_four; else if(tempsign = 1) /负数 if(k = 0)/显示符号位 P1 = commk; SEG = 0xbf; else if(k = 1) if(tens = 0) P1 = 0; else P1 = commk; SEG = segtens; else if(k = 2)/显示个位，因为各位有小数点，所以分开来显示 P1 = commk; SEG = seg_add_dicimalones; /要加上小数点 else /显示小数，0或5 P1 = commk; SEG = seg_dicimallow_four; k+; if(k = 4) k = 0