基于51单片机的DHT11湿度1602显示c程序

#include #define uint unsigned int #define uchar unsigned char sbit lcden=P2^7; sbit lcdrw=P2^5; sbit lcdrs=P2^6;

sbit DHT11_IO=P3^7; uint x,y,t;

uchar code table[]=\void Delay1()//延时10us { uchar i; i--; i--; i--; i--; i--; i--; }

void Delay2(uchar ms) { // 延时子程序 uchar i ; while(ms--) { for(i = 0 ; i<250;i++) ; } }

void mDelay(uchar delay) {

uchar i;

for(;delay>0;delay--) {

for(i=123;i>0;i--); } }

void delay(uint z) { for(x=z;x>0;x--) for(y=110;y>0;y--); }

void write_com(uchar com) {

lcdrs=0; lcdrw=0; P0=com; delay(5); lcden=1; delay(5); lcden=0; }

void init() { write_com(0x38); write_com(0x0c); write_com(0x06); write_com(0x01); write_com(0x80); }

void write_data(uchar dat) { lcdrs=1; lcdrw=0; P0=dat; delay(5); lcden=1; delay(5); lcden=0; }

void start(void)//开始信号 { DHT11_IO=1; Delay1(); DHT11_IO=0; Delay2(20);//>18ms DHT11_IO=1; Delay1();//20-40us Delay1(); Delay1(); Delay1(); Delay1(); }

uchar receive_byte(void)//接收一个字节 { uchar i,temp,count,data_byte;

for(i=0;i<8;i++) { while(!DHT11_IO);//等待50us低电平结束 temp=0; Delay1();Delay1();Delay1();Delay1(); if(DHT11_IO==1)temp=1; while(DHT11_IO); data_byte<<=1; data_byte|=temp; } return data_byte; }

void receive()//接收数据 { uchar check,num_check,HZ,HX,WZ,WX; start();//开始信号 DHT11_IO=1; if(!DHT11_IO)//读取DHT11响应信号 { while(!DHT11_IO);//DHT11高电平80us是否结束 while(DHT11_IO); HZ = receive_byte(); HX = receive_byte(); WZ = receive_byte(); WX = receive_byte(); check = receive_byte(); DHT11_IO=0;//拉低延时50us DHT11_IO=1; num_check = HZ + HX + WZ + WX; if(num_check = check) { check = num_check; } } write_com(0x80); write_data(table[HZ/10]); write_data(table[HZ]); write_data('.');

write_data(table[HX/10]); write_data(table[HX]); write_data('R'); write_data('H'); write_data('%');

// write_com(0x80+0x40); // write_data(table[WZ/10]); // write_data(table[WZ]); // write_data('.');

// write_data(table[WX/10]); // write_data(table[WX]); // write_data('T'); }

void main() {

init(); while(1) { receive(); } }