DHT11温湿度测量电路图及程序.doc

#include #define uint unsigned int #define uchar unsigned charsbit io=P10;/DHT11数据端sbit wela=P27;/ 数码管位选sbit dula=P26;/数码管段选uchar data_byte;uchar RH,RL,TH,TL;uchar table=0xc0,0xf9,0xa4,0xb0,0x99,0x92,0x82,0xf8,0x80,0x98;uchar wei=0x01,0x02,0x04,0x08,0x10,0x20,0x40,0x80;void delay(uchar z)uchar x,y;for(x=z;x0;x-)for(y=110;y0;y-);void delay1() /延时10usuchar i;i-;i-;i-;i-;i-;i-;void start()/开始信号io=1;delay1();io=0;delay(20);/18msio=1;delay1();/20-40usdelay1();delay1();delay1();delay1();uchar receive_byte()uchar i,temp,count;for(i=0;i8;i+)count=2;while(!io)&count+)/等待50us低电平结束temp=0;delay1();delay1();delay1();delay1();if(io=1)temp=1;count=2;while(io)&count+);if(count=1)break;data_byte=1;data_byte|=temp;return data_byte;void receive()uchar T_H,T_L,R_H,R_L,check,num_check;uchar count;start();/开始信号io=1;if(!io)/读取DHT11响应信号count=2;while(!io)&count+);/DHT11高电平80us是否结束count=2;while(io)&count+);R_H=receive_byte();R_L=receive_byte();T_H=receive_byte();T_L=receive_byte();check=receive_byte();io=0;/拉低延时50usdelay1();delay1();delay1();delay1();delay1();io=1;num_check=R_H+R_L+T_H+T_L;if(num_check=check)RH=R_H;RL=R_L;TH=T_H;TL=T_L;check=num_check;void display(uchar i,uchar j)/数码管显示P0=weii;wela=1;wela=0;P0=0xff;P0=tablej/10;dula=1;dula=0;delay(1);P0=0xff;P0=weii+1;wela=1;wela=0;P0=0xff;P0=tablej%10;dula=1;dula=0;delay(1);void main()while(1)receive();display(0,RH);delay(1);d