Create DHT.ino

Author: shramik49

examples/CommunitySubmitted/DHT/DHT.ino

@@ -0,0 +1,65 @@
+/*
+  Cayenne DHT Example
+  This sketch shows how to send DHT Sensor data to the Cayenne Dashboard.
+  The CayenneMQTT Library is required to run this sketch. If you have not already done so you can install it from the Arduino IDE Library Manager.
+
+  Steps:
+  1. Install DHT sensor library: https://github.com/adafruit/DHT-sensor-library.
+  2. Install Adafruit Unified Sensor Lib: https://github.com/adafruit/Adafruit_Sensor.
+  3. Attach a DHT to your Arduino:
+   Schematic:
+   DHT    Arduino
+   [VDD] --- [3V3]
+   [GND] --- [GND]
+   [OUTPUT] --- [Digital Pin 2]
+  4. Set the CELSIUS_TEMPERATURE_VIRTUAL_CHANNEL value below to a free virtual channel.
+  5. Set the HUMIDITY_VIRTUAL_CHANNEL value below to a free virtual channel.
+  6. Set the Cayenne authentication info to match the authentication info from the Dashboard.
+  7. Compile and upload this sketch.
+  8. Once the Arduino connects to the Dashboard it should automatically create temporary display widget with data.
+   To make a temporary widget permanent click the plus sign on the widget.
+*/
+
+#define CAYENNE_DEBUG
+#define CAYENNE_PRINT Serial // Comment this out to disable prints and save space
+#include <CayenneMQTTEthernet.h>
+#include <DHT.h>
+
+// Cayenne authentication info. This should be obtained from the Cayenne Dashboard.
+char username[] = "MQTT_USERNAME";
+char password[] = "MQTT_PASSWORD";
+char clientID[] = "CLIENT_ID";
+
+#define DHTPIN 2     // Digital pin connected to the DHT sensor
+
+// Uncomment whatever type you're using!
+#define DHTTYPE DHT11   // DHT 11
+//#define DHTTYPE DHT22   // DHT 22  (AM2302), AM2321
+//#define DHTTYPE DHT21   // DHT 21 (AM2301)
+
+#define TEMPERATURE_VIRTUAL_CHANNEL 1
+#define HUMIDITY_VIRTUAL_CHANNEL 2
+
+DHT dht(DHTPIN, DHTTYPE); // Initialize DHT sensor.
+
+void setup() {
+  Serial.begin(9600);
+  Cayenne.begin(username, password, clientID);
+  dht.begin();
+}
+
+void loop() {
+  Cayenne.loop();
+}
+
+// This function is called at intervals to send temperature sensor data to Cayenne in Celsius.
+CAYENNE_OUT(TEMPERATURE_VIRTUAL_CHANNEL)
+{
+  Cayenne.virtualWrite(TEMPERATURE_VIRTUAL_CHANNEL, dht.readTemperature(), "temp", "c");
+}
+
+// This function is called at intervals to send humidity sensor data to Cayenne.
+CAYENNE_OUT(HUMIDITY_VIRTUAL_CHANNEL)
+{
+  Cayenne.virtualWrite(HUMIDITY_VIRTUAL_CHANNEL, dht.readHumidity(), "rel_hum", "p");
+}