Muhammad Afzal
Published © Apache-2.0

Temperature Monitoring with Arduino IoT Cloud using DHT22

In this project you will learn how to monitor temperature & humidity using DHT22 sensor and MKR WiFi 1010 with Arduino IoT Cloud.

BeginnerFull instructions provided3 hours448
Temperature Monitoring with Arduino IoT Cloud using DHT22

Things used in this project

Hardware components

Arduino MKR WiFi 1010
Arduino MKR WiFi 1010
×1
DHT22 Temperature Sensor
DHT22 Temperature Sensor
×1
Jumper wires (generic)
Jumper wires (generic)
×1
PHPoC Bread Board
PHPoC Bread Board
×1

Software apps and online services

Arduino Create Agent
Arduino IoT Cloud
Arduino IoT Cloud

Story

Read more

Code

Arduino IoT Cloud Thing MKR WiFi 1010 and DHT22

Arduino
Temperature and Humidity monitoring using MKR Wi-Fi 1010 and DHT22 by using Arduino IoT Cloud
/* 
  Sketch generated by the Arduino IoT Cloud Thing "MKR WiFi 1010 and DHT22"
  https://create.arduino.cc/cloud/things/e75efe13-eb5e-432a-86d3-0bf1cd34aaac 

  Arduino IoT Cloud Variables description

  The following variables are automatically generated and updated when changes are made to the Thing

  CloudTemperatureSensor temperature;
  CloudRelativeHumidity humidity;

  Variables which are marked as READ/WRITE in the Cloud Thing will also have functions
  which are called when their values are changed from the Dashboard.
  These functions are generated with the Thing and added at the end of this sketch.
*/

#include "thingProperties.h"
#include <Adafruit_Sensor.h>
#include <DHT.h>
#include <DHT_U.h>

#define DHTPIN 7    // Digital pin connected to the DHT sensor 
#define DHTTYPE    DHT22     // Write DHT11 or DHT22 According to your Sensor

DHT_Unified dht(DHTPIN, DHTTYPE);
uint32_t delayMS;
unsigned long previousMillis = 0;
const long interval = 20000; //milliseconds  total time for 20 Seconds



void setup() {
  // Initialize serial and wait for port to open:
  Serial.begin(9600);
  // This delay gives the chance to wait for a Serial Monitor without blocking if none is found
  delay(1500); 

  // Defined in thingProperties.h
  initProperties();

  // Connect to Arduino IoT Cloud
  ArduinoCloud.begin(ArduinoIoTPreferredConnection);
  
  /*
     The following function allows you to obtain more information
     related to the state of network and IoT Cloud connection and errors
     the higher number the more granular information you’ll get.
     The default is 0 (only errors).
     Maximum is 4
 */
  setDebugMessageLevel(2);
  ArduinoCloud.printDebugInfo();

  dht.begin(); //Init DHT

  Serial.println(F("DHTxx Unified Sensor Example"));
  // Print temperature sensor details.
  sensor_t sensor;
  dht.temperature().getSensor(&sensor);
  Serial.println(F("------------------------------------"));
  Serial.println(F("Temperature Sensor"));
  Serial.print  (F("Sensor Type: ")); Serial.println(sensor.name);
  Serial.print  (F("Driver Ver:  ")); Serial.println(sensor.version);
  Serial.print  (F("Unique ID:   ")); Serial.println(sensor.sensor_id);
  Serial.print  (F("Max Value:   ")); Serial.print(sensor.max_value); Serial.println(F("°C"));
  Serial.print  (F("Min Value:   ")); Serial.print(sensor.min_value); Serial.println(F("°C"));
  Serial.print  (F("Resolution:  ")); Serial.print(sensor.resolution); Serial.println(F("°C"));
  Serial.println(F("------------------------------------"));
  // Print humidity sensor details.
  dht.humidity().getSensor(&sensor);
  Serial.println(F("Humidity Sensor"));
  Serial.print  (F("Sensor Type: ")); Serial.println(sensor.name);
  Serial.print  (F("Driver Ver:  ")); Serial.println(sensor.version);
  Serial.print  (F("Unique ID:   ")); Serial.println(sensor.sensor_id);
  Serial.print  (F("Max Value:   ")); Serial.print(sensor.max_value); Serial.println(F("%"));
  Serial.print  (F("Min Value:   ")); Serial.print(sensor.min_value); Serial.println(F("%"));
  Serial.print  (F("Resolution:  ")); Serial.print(sensor.resolution); Serial.println(F("%"));
  Serial.println(F("------------------------------------"));
  // Set delay between sensor readings based on sensor details.
  delayMS = sensor.min_delay / 1000;
  STHAM();
  
}

void loop() {
  ArduinoCloud.update();
  // Your code here 
  
  unsigned long currentMillis = millis();
  if (currentMillis - previousMillis >= interval) {
    STHAM();
    previousMillis = currentMillis;
  }
}


void STHAM(){
  // Get temperature event and print its value.
  sensors_event_t event;
  dht.temperature().getEvent(&event);
  if (isnan(event.temperature)) {
    Serial.println(F("Error reading temperature!"));
    //Assign temperature value 0 to Cloud Variable
    temperature=0;
  }
  else {
    Serial.print(F("Temperature: "));
    Serial.print(event.temperature);
    Serial.println(F("°C"));
    //Assign temperature value to Cloud Variable
    temperature=event.temperature;
  }
  
  // Get humidity event and print its value.
  dht.humidity().getEvent(&event);
  if (isnan(event.relative_humidity)) {
    Serial.println(F("Error reading humidity!"));
    //Assign humidity value 0 to Cloud Variable
    humidity=0;
  }
  else {
    Serial.print(F("Humidity: "));
    Serial.print(event.relative_humidity);
    Serial.println(F("%"));
    //Assign humidity value to Cloud Variable
    humidity=event.relative_humidity;
  }
}

/*
  Since Temperature is READ_WRITE variable, onTemperatureChange() is
  executed every time a new value is received from IoT Cloud.
*/
void onTemperatureChange()  {
  // Add your code here to act upon Temperature change
}

/*
  Since Humidity is READ_WRITE variable, onHumidityChange() is
  executed every time a new value is received from IoT Cloud.
*/
void onHumidityChange()  {
  // Add your code here to act upon Humidity change
}

Credits

Muhammad Afzal

Muhammad Afzal

25 projects • 117 followers
I am Software Eng having 13+ Years of experience. Hackster.io & Cayenne Mydevices Ambassador in Pakistan.

Comments

Related channels and tags
  • Arduino
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