本教程使用的温湿度传感器模块为：Temperature-Humidity Sensor，先晒张美图：
模块采用的温湿度传感器为：DHT11，DHT11 数字温湿度传感器是一款含有已校准数字信号输出的温湿度复 合传感器。它包括一个电阻式感湿元件和一个 NTC 测温元件。每个 DHT11 传 感器都在极为精确的湿度校验室中进行校准。校准系数以程序的形式储存在 OTP 内存中，传感器内部在检测信号的处理过程中要调用这些校准系数,用户 无需重新校准。单线制串行接口，使系统集成变得简易快捷。超小的体积、 极低的功耗，信号传输距离可达 20 米以上。 硬件准备：
硬件连接：
将UNO PLUS的电压配置为5V， 模块引脚连接如下： 程序： double Fahrenheit(double celsius)
{
return 1.8 * celsius + 32;
}
double Kelvin(double celsius)
{
return celsius + 273.15;
}
double dewPoint(double celsius, double humidity)
{
double A0= 373.15/(273.15 + celsius);
double SUM = -7.90298 * (A0-1);
SUM += 5.02808 * log10(A0);
SUM += -1.3816e-7 * (pow(10, (11.344*(1-1/A0)))-1) ;
SUM += 8.1328e-3 * (pow(10,(-3.49149*(A0-1)))-1) ;
SUM += log10(1013.246);
double VP = pow(10, SUM-3) * humidity;
double T = log(VP/0.61078); // temp var
return (241.88 * T) / (17.558-T);
}
double dewPointFast(double celsius, double humidity)
{
double a = 17.271;
double b = 237.7;
double temp = (a * celsius) / (b + celsius) + log(humidity/100);
double Td = (b * temp) / (a - temp);
return Td;
}
#include
dht11 DHT11;
#define DHT11PIN 2
void setup()
{
Serial.begin(9600);
Serial.println("DHT11 TEST PROGRAM ");
Serial.print("LIBRARY VERSION: ");
Serial.println(DHT11LIB_VERSION);
Serial.println();
}
void loop()
{
Serial.println("\n");
int chk = DHT11.read(DHT11PIN);
Serial.print("Read sensor: ");
switch (chk)
{
case DHTLIB_OK:
Serial.println("OK");
break;
case DHTLIB_ERROR_CHECKSUM:
Serial.println("Checksum error");
break;
case DHTLIB_ERROR_TIMEOUT:
Serial.println("Time out error");
break;
default:
Serial.println("Unknown error");
break;
}
Serial.print("Humidity (%): ");
Serial.println((float)DHT11.humidity, 2);
Serial.print("Temperature (oC): ");
Serial.println((float)DHT11.temperature, 2);
Serial.print("Temperature (oF): ");
Serial.println(Fahrenheit(DHT11.temperature), 2);
Serial.print("Temperature (K): ");
Serial.println(Kelvin(DHT11.temperature), 2);
Serial.print("Dew Point (oC): ");
Serial.println(dewPoint(DHT11.temperature, DHT11.humidity));
Serial.print("Dew PointFast (oC): ");
Serial.println(dewPointFast(DHT11.temperature, DHT11.humidity));
delay(2000);
} 现象：
附件： |
