Arduino - Humidity Sensor

1// Example testing sketch for various DHT humidity/temperature sensors
2
3#include  "DHT.h"
4#define DHTPIN 2 // what digital pin we're connected to
5// Uncomment  whatever type you're using!
6//#define DHTTYPE DHT11 // DHT 11
7#define DHTTYPE  DHT22 // DHT 22 (AM2302), AM2321
8//#define DHTTYPE DHT21 // DHT 21 (AM2301)
9//  Connect pin 1 (on the left) of the sensor to +5V
10// NOTE: If using a board with  3.3V logic like an Arduino Due connect pin 1
11// to 3.3V instead of 5V!
12//  Connect pin 2 of the sensor to whatever your DHTPIN is
13// Connect pin 4 (on the  right) of the sensor to GROUND
14// Connect a 10K resistor from pin 2 (data) to  pin 1 (power) of the sensor
15// Initialize DHT sensor.
16// Note that older versions  of this library took an optional third parameter to
17// tweak the timings for  faster processors. This parameter is no longer needed
18// as the current DHT reading  algorithm adjusts itself to work on faster procs.
19DHT dht(DHTPIN, DHTTYPE);
20
21void  setup() {
22   Serial.begin(9600);
23   Serial.println("DHTxx test!");
24   dht.begin();
25}
26
27void  loop() {
28   delay(2000); // Wait a few seconds between measurements
29   float  h = dht.readHumidity();
30   // Reading temperature or humidity takes about 250  milliseconds!
31   float t = dht.readTemperature();
32   // Read temperature as  Celsius (the default)
33   float f = dht.readTemperature(true);
34   // Read temperature  as Fahrenheit (isFahrenheit = true)
35   // Check if any reads failed and exit  early (to try again).
36   if (isnan(h) || isnan(t) || isnan(f)) {
37      Serial.println("Failed  to read from DHT sensor!");
38      return;
39   }
40   
41   // Compute heat  index in Fahrenheit (the default)
42   float hif = dht.computeHeatIndex(f, h);
43   // Compute heat index in Celsius (isFahreheit = false)
44   float hic = dht.computeHeatIndex(t,  h, false);
45   Serial.print ("Humidity: ");
46   Serial.print (h);
47   Serial.print  (" %\	");
48   Serial.print ("Temperature: ");
49   Serial.print (t);
50   Serial.print (" *C ");
51   Serial.print (f);
52   Serial.print (" *F\	");
53   Serial.print ("Heat index: ");
54   Serial.print (hic);
55   Serial.print  (" *C ");
56   Serial.print (hif);
57   Serial.println (" *F");
58}

1// Example testing sketch for various DHT humidity/temperature sensors
2
3#include   "DHT.h"
4#define DHTPIN 2 // what digital pin we're connected to
5// Uncomment   whatever type you're using!
6//#define DHTTYPE DHT11 // DHT 11
7#define DHTTYPE   DHT22 // DHT 22 (AM2302), AM2321
8//#define DHTTYPE DHT21 // DHT 21 (AM2301)
9//   Connect pin 1 (on the left) of the sensor to +5V
10// NOTE: If using a board with   3.3V logic like an Arduino Due connect pin 1
11// to 3.3V instead of 5V!
12//   Connect pin 2 of the sensor to whatever your DHTPIN is
13// Connect pin 4 (on the   right) of the sensor to GROUND
14// Connect a 10K resistor from pin 2 (data) to   pin 1 (power) of the sensor
15// Initialize DHT sensor.
16// Note that older versions   of this library took an optional third parameter to
17// tweak the timings for   faster processors. This parameter is no longer needed
18// as the current DHT reading   algorithm adjusts itself to work on faster procs.
19DHT dht(DHTPIN, DHTTYPE);
20
21void   setup() {
22   Serial.begin(9600);
23   Serial.println("DHTxx test!");
24   dht.begin();
25}
26
27void   loop() {
28   delay(2000); // Wait a few seconds between measurements
29   float   h = dht.readHumidity();
30   // Reading temperature or humidity takes about 250   milliseconds!
31   float t = dht.readTemperature();
32   // Read temperature as   Celsius (the default)
33   float f = dht.readTemperature(true);
34   // Read temperature   as Fahrenheit (isFahrenheit = true)
35   // Check if any reads failed and exit   early (to try again).
36   if (isnan(h) || isnan(t) || isnan(f)) {
37      Serial.println("Failed   to read from DHT sensor!");
38      return;
39   }
40   
41   // Compute heat   index in Fahrenheit (the default)
42   float hif = dht.computeHeatIndex(f, h);
43    // Compute heat index in Celsius (isFahreheit = false)
44   float hic = dht.computeHeatIndex(t,   h, false);
45   Serial.print ("Humidity: ");
46   Serial.print (h);
47   Serial.print   (" %\	");
48   Serial.print ("Temperature: ");
49   Serial.print (t);
50    Serial.print (" *C ");
51   Serial.print (f);
52   Serial.print (" *F\	");
53    Serial.print ("Heat index: ");
54   Serial.print (hic);
55   Serial.print   (" *C ");
56   Serial.print (hif);
57   Serial.println (" *F");
58}