最近忍痛买了一块正版的Arduino UNO，80多块，真的贵，都能买一个NanoPiNEO了。不过正版的做工确实好，性能也稳定。

所以之前买的兼容版就又拿来做点东西啦，这次是一个简单的温湿度计。

硬件：

Arduino UNO一块

DHT11温湿度模块一个

IIC1602显示模块一个

Arduino UNO底板一块

杜邦线若干

连接：

IIC1602:

VCC — VCC
GND — GND

SDA — SDA
SCL — SCL

DHT11：

VCC — VCC

GND — GND

DAT — pin12

照例先检测1602的地址，代码见：http://blog.readgroup.cn/post/52，不再重复了。

DHT11的库自带有，没有的话用这个：https://github.com/adafruit/DHT-sensor-library

基础库：https://github.com/adafruit/Adafruit_Sensor

代码：

//DHT11 Sensor:
#include "DHT.h"
#define DHTPIN 12     // what digital pin we're connected to
#define DHTTYPE DHT11   // DHT 11

DHT dht(DHTPIN, DHTTYPE);


//I2C LCD:
#include <Wire.h> // Comes with Arduino IDE
#include <LiquidCrystal_I2C.h>

// Set the LCD I2C address
LiquidCrystal_I2C lcd(0x27,16,2);


void setup() {
  Serial.begin(9600);
  lcd.begin(16,2);
  Serial.println("Mohamed Chaara Temp and Humidity Sensor Test");

  dht.begin();
}

void loop() {
    // Reading temperature or humidity takes about 250 milliseconds!
  // Sensor readings may also be up to 2 seconds 'old' (its a very slow sensor)
  int h = dht.readHumidity();
  int t = dht.readTemperature();

    // set the cursor to (0,0):
    lcd.init();  
    lcd.backlight();
  lcd.setCursor(0, 0);
  // print from 0 to 9:

   lcd.print("Temp: ");
   lcd.print(t);
   lcd.write(0xDF);
   lcd.print("C");
  
  // set the cursor to (16,1):
  lcd.setCursor(0,1);
  lcd.print("Humidity: ");
  lcd.print(h);
  lcd.print("%");
    
  Serial.print("Temp: ");
  Serial.print(t);
  Serial.print("C, Humidity: ");
  Serial.print(h);
  Serial.println("%");

}

参考文章：http://www.instructables.com/id/Arduino-TempHumidity-Sensor-Using-DHT11-and-I2C-LC/