Arduino 湿度传感器

由 drbear 创建，youj 最后一次修改 2016-12-26 在本节中，我们将学习如何使用不同的传感器连接我们的Arduino板。我们将讨论以下传感器： 湿度传感器（DHT22）温度传感器（LM35）水位检测传感器（简单水触发器）PIR传感器超声波传感器GPS湿度传感器(DHT22)DHT-22（也称为AM2302）是一个数字输出，相对湿度和温度传感器。它使用电容式湿度传感器和热敏电阻来测量周围空气，并在数据引脚上发送数字信号。在本例中，你将学习如何将此传感器与Arduino UNO一起使用。室温和湿度将打印到串口监视器上。DHT-22传感器连接很简单。左边的第一个引脚为3-5V电源，第二个引脚连接到数据输入引脚，最右边的引脚接地。技术细节电源 - 3-5V最大电流 - 2.5mA湿度 - 0-100％，精确度为2-5％温度 - 40至80°C，精确度为±0.5°C必需的组件你将需要以下组件： 1 × Breadboard 面包板1 × Arduino Uno R31 × DHT221 × 10K欧姆电阻程序按照电路图连接面包板上的组件，如下图所示。草图在计算机上打开Arduino IDE软件。使用Arduino语言进行编码控制你的电路。通过单击“New”打开一个新的草图文件。Arduino代码// Example testing sketch for various DHT humidity/temperature sensors#include "DHT.h"#define DHTPIN 2 // what digital pin we're connected to// Uncomment whatever type you're using!//#define DHTTYPE DHT11 // DHT 11#define DHTTYPE DHT22 // DHT 22 (AM2302), AM2321//#define DHTTYPE DHT21 // DHT 21 (AM2301)// Connect pin 1 (on the left) of the sensor to +5V// NOTE: If using a board with 3.3V logic like an Arduino Due connect pin 1// to 3.3V instead of 5V!// Connect pin 2 of the sensor to whatever your DHTPIN is// Connect pin 4 (on the right) of the sensor to GROUND// Connect a 10K resistor from pin 2 (data) to pin 1 (power) of the sensor// Initialize DHT sensor.// Note that older versions of this library took an optional third parameter to// tweak the timings for faster processors. This parameter is no longer needed// as the current DHT reading algorithm adjusts itself to work on faster procs.DHT dht(DHTPIN, DHTTYPE);void setup() { Serial.begin(9600); Serial.println("DHTxx test!"); dht.begin();}void loop() { delay(2000); // Wait a few seconds between measurements float h = dht.readHumidity(); // Reading temperature or humidity takes about 250 milliseconds! float t = dht.readTemperature(); // Read temperature as Celsius (the default) float f = dht.readTemperature(true); // Read temperature as Fahrenheit (isFahrenheit = true) // Check if any reads failed and exit early (to try again). if (isnan(h) || isnan(t) || isnan(f)) { Serial.println("Failed to read from DHT sensor!"); return; } // Compute heat index in Fahrenheit (the default) float hif = dht.computeHeatIndex(f, h); // Compute heat index in Celsius (isFahreheit = false) float hic = dht.computeHeatIndex(t, h, false); Serial.print ("Humidity: "); Serial.print (h); Serial.print (" %\t"); Serial.print ("Temperature: "); Serial.print (t); Serial.print (" *C "); Serial.print (f); Serial.print (" *F\t"); Serial.print ("Heat index: "); Serial.print (hic); Serial.print (" *C "); Serial.print (hif); Serial.println (" *F");}代码说明DHT22传感器具有四个端子连接到电路板的端子（Vcc，DATA，NC，GND），如下：DATA引脚连接到Arduino的2号引脚号Vcc引脚连接到Arduino板的5伏电压GND引脚连接到Arduino板的接地我们需要在DATA和Vcc引脚之间连接10k欧姆电阻（上拉电阻）一旦硬件连接完成，你需要添加DHT22库到你的Arduino库文件，如前所述。结果你将看到串口监视器上的温度和湿度显示，每2秒更新一次。