// Example testing sketch for various DHT humidity/temperature sensors // Written by ladyada, public domain #include "DHT.h" //#define CAYENNE_DEBUG // Cayenne Code Uncomment to show debug messages #define DHTPIN 2 // what digital pin we're connected to #define CAYENNE_PRINT Serial // Cayenne Code Comment this out to disable prints and save space #include // Cayenne Code Change this to use a different communication device. See Communications examples. // Cayenne authentication token. This should be obtained from the Cayenne Dashboard. char token[] = "a5np0w1hz4"; // 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!"); Cayenne.begin(token); dht.begin(); } void loop() { Cayenne.run(); // Wait a few seconds between measurements. delay(10000); // Reading temperature or humidity takes about 250 milliseconds! // Sensor readings may also be up to 2 seconds 'old' (its a very slow sensor) float h = dht.readHumidity(); // Read temperature as Celsius (the default) float t = dht.readTemperature(); // Read temperature as Fahrenheit (isFahrenheit = true) float f = dht.readTemperature(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"); } // These functions are called when the Cayenne widget requests data for the Virtual Pin. CAYENNE_OUT(V0) { Cayenne.virtualWrite(V0, dht.readTemperature(true)); } CAYENNE_OUT(V1) { Cayenne.virtualWrite(V1, dht.readHumidity()); } CAYENNE_OUT(V2) { Cayenne.virtualWrite(V2, dht.readTemperature()); } CAYENNE_OUT(V3) { Cayenne.virtualWrite(V3, dht.readHumidity()); } CAYENNE_OUT(V4) { Cayenne.virtualWrite(V4, dht.readTemperature(true)); }