基于STM8的DHT11温湿度传感器的驱动代码设计

#include "typedef.h"

#include

#include "TemDHT11.h"

#ifndef _DHT11_TYPE

#define _DHT11_TYPE

//连接端口

#define DHT11_Dir P2DIR

#define DHT11_In P2IN

#define DHT11_Out P2OUT

#define DHT11_Bit BIT4

#endif

//8bit湿度+8bit湿度小数点

//8bit温度+8bit温度小数点

//数据位为0是高电平26~28us | 1高电平70us

u8 DHT11_Data[5] = {0}; //从DHT11中读到的数据

void read_DHT11(u8 *Data)

{

u8 re,m,n,Time_out;

DHT11_Dir &= (~DHT11_Bit); //引脚为输入

for(n = 0; n < 5; n++)

{

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

{

while( !(DHT11_In & DHT11_Bit) ); //每1bit以50us低电平时限开始，直到高电平到来

delay_us(30);

re = 0;

if((DHT11_In & DHT11_Bit)) //30us后还是高电平说明是1

{

re = 1;

}

Time_out = 2;

while((DHT11_In & DHT11_Bit) && (Time_out++ ));

if(Time_out == 1) //超时处理

{

break;

}

*Data <<= 1;

if(re)

{

*Data |= 0x01;

}

}

Data++;

}

}

//DHT11的握手协议模拟和数据的读取

u8 DHT11_GetData(void)

{

u8 o,sum;

DHT11_Dir |= DHT11_Bit;

DHT11_Out &= ~DHT11_Bit; //拉低，发出开始信号

delay_ms(18); //拉低18ms

DHT11_Out |= DHT11_Bit; //拉高20us等待

delay_us(20);

DHT11_Dir &= (~DHT11_Bit);

if( !(DHT11_In & DHT11_Bit) ) //DHT11响应

{

while( !(DHT11_In & DHT11_Bit) ); //80us低电平，等待DHT11的响应信号

while( (DHT11_In & DHT11_Bit) ); //DHT11准备发送数据

read_DHT11(DHT11_Data); //主机接收数据

sum = 0;

for(o = 0; o < 4; o++) //数据校验

{

sum += DHT11_Data[o];

}

if(sum != DHT11_Data[4])

{

return 0;

}

else

{

return 1;

}

}

return 0;

}

//对温度湿度进行格式化(如果获取温度成功)

void DHT11_format(char *Des_str)

{

Des_str[0] = DHT11_Data[0]/10 + 0x30;

Des_str[1] = DHT11_Data[0] + 0x30;

Des_str[2] = '.';

Des_str[3] = DHT11_Data[1]/10 + 0x30;

Des_str[4] = DHT11_Data[1] + 0x30;

Des_str[5] = '%';

Des_str[6] = ' ';

Des_str[7] = DHT11_Data[2]/10 + 0x30;

Des_str[8] = DHT11_Data[2] + 0x30;

Des_str[9] = '.';

Des_str[10] = DHT11_Data[3]/10 + 0x30;

Des_str[11] = DHT11_Data[3] + 0x30;

Des_str[12] = 'C';

Des_str[13] = 0;

}