数码管显示温度 原理图+程序

1、原理图：程序：#include / 包括一个52标准内核的头文件#include /_nop_(; 延时函数用sbit DQ=P33; /温度输入口sbit P07=P07; /LED小数点控制/ sbit P20=P20;sbit SPEA=P37;sbit P17=P17;unsigned int h,n=0; unsigned int temp;void delay(unsigned int t;void delay882us(void;ow_reset(void;void write_byte(unsigned char val;unsigned char read_byte(void

2、;unsigned int read_temp(;void delayms(unsigned int ms;void runled(void;void light(void;void x8led(unsigned long ddd;/*温度小数部分用查表法*/unsigned char data temp_data2=0x00,0x00; /读出温度暂放unsigned char data display5=0x00,0x00,0x00,0x00,0x00; /显示单元数据，共4个数据和一个运算暂用/*11us延时函数*/void delay(unsigned int tfor (;t>

3、0;t-;/*延时882us*/void delay882us(voidunsigned char i;for(i=0;i<255;i+;_nop_(;/*DS18B20复位函数*/ow_reset(voidchar presence=1;while(presencewhile(presenceDQ=1;_nop_(;_nop_(;/从高拉倒低DQ=0; delay(50; /550 usDQ=1; delay(6; /66 uspresence=DQ; /presence=0 复位成功,继续下一步 delay(45; /延时500 uspresence=DQ; DQ=1; /拉高电平/

4、*DS18B20写命令函数*/向1-WIRE 总线上写1个字节void write_byte(unsigned char val unsigned char i;for(i=8;i>0;i-DQ=1;_nop_(;_nop_(; /从高拉倒低DQ=0;_nop_(;_nop_(;_nop_(;_nop_(; /5 usDQ=val&0x01; /最低位移出delay(6; /66 usval=val/2; /右移1位DQ=1;delay(1;/*DS18B20读1字节函数*/从总线上取1个字节unsigned char read_byte(voidunsigned char i;

5、unsigned char value=0;for(i=8;i>0;i-DQ=1;_nop_(;_nop_(;value>>=1;DQ=0;_nop_(;_nop_(;_nop_(;_nop_(; /4 usDQ=1;_nop_(;_nop_(;_nop_(;_nop_(; /4 usif(DQvalue|=0x80;delay(6; /66 usDQ=1;return(value;/*读出温度函数*/unsigned int read_temp(ow_reset(; /总线复位delay(200;write_byte(0xcc; /发命令write_byte(0x44; /

6、发转换命令ow_reset(; delay(1;write_byte(0xcc; /发命令write_byte(0xbe;temp_data0=read_byte(; /读温度值的第字节temp_data1=read_byte(; /读温度值的高字节temp=temp_data1;temp<<=8; temp=temp|temp_data0; / 两字节合成一个整型变量。if(temp>6348temp=65536-temp;n=1;display4=temp&0x0f; / 取小数部分的值temp=temp>>4; / 取中间八位,即整数部分的值temp

7、=temp*10+display4;return temp; /返回温度值void delayms(unsigned int msunsigned int i,j;for(i=20;i>0;i- x8led(temp; for(j=ms;j>0;j- _nop_(;void runled(voidunsigned int i,a=0x01;for(i=0;i<8;i+P1=a;a<<=1;delayms(50;void light(voidP1=0;delayms(10;P1=0XFF;delayms(10;/*数码管扫描*/void x8led(unsigned

8、 long dddunsigned char q,r=0;unsigned char l13=0xc0,0xf9,0xa4,0xb0,0x99,0x92,0x82,0xf8,0x80,0x90,0x7f,0xbf,0xff;/0-9的字段码unsigned char xx4=0,0,0,0;unsigned char y4=0x8,0x4,0x2,0x1;xx3=ddd%10;xx2=ddd/10%10;xx1=ddd/100%10;if(n=1/ n=0;xx0=11; /显示“-”号else xx0=12; /无任何显示for(q=0;q<4; /循环扫描q+;r+;if(r=4r=0;P2=yr; P0=lxxr;if(r=2P07=0;delay(100;P0=0xff; /*主函数*/void main(P0=0xff; /初始化端口P2=0xff;for(h=0;h<4;h+ /开机显示"000"displayh=0; ow_reset(; /开机先转换一次write_byte(0xcc; /Skip ROMwrite_byte(0x44; /发转换命令for(h=0;h<200;h