Difference between revisions of "Temperature and Humidity Sensor"

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(Test tools and test)
(Test tools and test)
Line 45: Line 45:
 
   { 
 
   { 
 
    DHT22_ERROR_t errorCode;
 
    DHT22_ERROR_t errorCode;
   // The sensor can only be read from every 1-2s, and requires a minimum
+
  // The sensor can only be read from every 1-2s, and requires a minimum
   // 2s warm-up after power-on.
+
  // 2s warm-up after power-on.
   delay(2000);
+
  delay(2000);
   Serial.print("Requesting data...");
 
   errorCode = myDHT22.readData();
 
   switch(errorCode)
 
   {
 
     case DHT_ERROR_NONE:
 
       Serial.print("Got Data ");
 
       Serial.print(myDHT22.getTemperatureC());
 
       Serial.print("C ");
 
       Serial.print(myDHT22.getHumidity());
 
       Serial.println("%");
 
       // Alternately, with integer formatting which is clumsier but more compact to store and
 
       // can be compared reliably for equality:
 
       //      
 
       char buf[128];
 
       sprintf(buf, "Integer-only reading: Temperature %hi.%01hi C, Humidity %i.%01i %% RH",
 
                    myDHT22.getTemperatureCInt()/10, abs(myDHT22.getTemperatureCInt()%10),
 
                    myDHT22.getHumidityInt()/10, myDHT22.getHumidityInt()%10);
 
       Serial.println(buf);
 
       break;
 
     case DHT_ERROR_CHECKSUM:
 
       Serial.print("check sum error ");
 
       Serial.print(myDHT22.getTemperatureC());
 
       Serial.print("C ");
 
       Serial.print(myDHT22.getHumidity());
 
       Serial.println("%");
 
       break;
 
     case DHT_BUS_HUNG:
 
       Serial.println("BUS Hung ");
 
       break;
 
     case DHT_ERROR_NOT_PRESENT:
 
       Serial.println("Not Present ");
 
       break;
 
     case DHT_ERROR_ACK_TOO_LONG:
 
       Serial.println("ACK time out ");
 
       break;
 
     case DHT_ERROR_SYNC_TIMEOUT:
 
       Serial.println("Sync Timeout ");
 
       break;
 
     case DHT_ERROR_DATA_TIMEOUT:
 
       Serial.println("Data Timeout ");
 
       break;
 
     case DHT_ERROR_TOOQUICK:
 
       Serial.println("Polled to quick ");
 
       break;
 
    }
 
  
 +
  Serial.print("Requesting data...");
 +
  errorCode = myDHT22.readData();
 +
  switch(errorCode)
 +
  {
 
(3)Test Results
 
(3)Test Results
  

Revision as of 11:05, 19 April 2016

Introduction

This is a powerful sister version of our Linker kit - Temperature and Humidity Sensor. It has more complete and accurate performance. The detecting range of this sensor is 5% RH - 99% RH, and -40°C - 80°C. And its accuracy satisfyingly reaches up to 2% RH and 0.5°C. A professional choice for applications that have relatively strict requirements.

1-214.jpg

1-215.jpg


Specification

1-209.jpg

Platforms Supported

  • Arduino
  • Raspberry Pi

Test

Test tools and test

(1)Test tools

  • Arduino UNO x 1 
  • Linker Base Shield x 1
  • Linker temperature & humidity sensor x1

1-210.png

(2)、Program

  #include <DHT22.h>
  // Only used for sprintf
  #include <stdio.h>
  // Data wire is plugged into port 7 on the Arduino
  // Connect a 4.7K resistor between VCC and the data pin (strong pullup)
  #define DHT22_PIN 7
  // Setup a DHT22 instance
  DHT22 myDHT22(DHT22_PIN);
  void setup(void)
 {

   // start serial port    Serial.begin(9600);    Serial.println("DHT22 Library Demo");

  }
  void loop(void)
  { 
  DHT22_ERROR_t errorCode;

  // The sensor can only be read from every 1-2s, and requires a minimum   // 2s warm-up after power-on.   delay(2000);

  Serial.print("Requesting data...");   errorCode = myDHT22.readData();   switch(errorCode)   { (3)Test Results

1-211.png

Documents

Test code download