IoT – ESP32 And Thingspeak

				
					 #include <WiFi.h>

#include <WiFiMulti.h>

#include "DHT.h"

#define DHTPIN 2    

#define DHTTYPE DHT11  

DHT dht(DHTPIN, DHTTYPE);

 

WiFiMulti WiFiMulti;

const char* ssid     = "Amplifiers"; // Your SSID (Name of your WiFi)

const char* password = "Ak*****"; //Your Wifi password

const char* host = "api.thingspeak.com";

String api_key = "F3UD*********T5L7"; // Your API Key provied by thingspeak

void setup(){

  Serial.begin(9600);

   Serial.println(F("DHTxx test!"));

  dht.begin();

  Connect_to_Wifi();

}

void loop(){

   float h = dht.readHumidity();

  float t = dht.readTemperature();

  float f = dht.readTemperature(true);

  if (isnan(h) || isnan(t) || isnan(f)) {

    Serial.println(F("Failed to read from DHT sensor!"));

    return;

  }

   Serial.print(F("Humidity: "));

  Serial.print(h);

  Serial.print(F("%  Temperature: "));

  Serial.print(t);

  Serial.println(F("°C "));

  

 // call function to send data to Thingspeak

  Send_Data(t,h);

  delay(5000);

 

}

void Connect_to_Wifi()

{

  // We start by connecting to a WiFi network

  WiFiMulti.addAP(ssid, password);

  Serial.println();

  Serial.println();

  Serial.print("Wait for WiFi... ");

  while (WiFiMulti.run() != WL_CONNECTED) {

    Serial.print(".");

    delay(500);

  }

  Serial.println("");

  Serial.println("WiFi connected");

  Serial.println("IP address: ");

  Serial.println(WiFi.localIP());

}

void Send_Data(float t, float h)

{

  // map the moist to 0 and 100% for a nice overview in thingspeak.

  Serial.println("");

  Serial.println("Prepare to send data");

  // Use WiFiClient class to create TCP connections

  WiFiClient client;

  const int httpPort = 80;

  if (!client.connect(host, httpPort)) {

    Serial.println("connection failed");

    return;

  }

  else

  {

    String data_to_send = api_key;

    data_to_send += "&field1=";

    data_to_send += String(t);

    data_to_send += "&field2=";

    data_to_send += String(h);

    // data_to_send += "&field3=";

    // data_to_send += String(pressure);

    data_to_send += "\r\n\r\n";

    client.print("POST /update HTTP/1.1\n");

    client.print("Host: api.thingspeak.com\n");

    client.print("Connection: close\n");

    client.print("X-THINGSPEAKAPIKEY: " + api_key + "\n");

    client.print("Content-Type: application/x-www-form-urlencoded\n");

    client.print("Content-Length: ");

    client.print(data_to_send.length());

    client.print("\n\n");

    client.print(data_to_send);

    delay(1000);

  }

  client.stop();

}