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Room Temperature and
Humidity Publish in Think Speak
IoT Cloud Server Using DHT11
Department of Electrical Engineering
Gargi Memorial Institute of Technology
Name of the Student: RAHUL NASKAR
Present Semester: 7th
Class Roll No.:
University Roll No.: 28101619020
Paper Name: PROJECT STAGE - 1
Paper Code: PW-EE-781

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APPARATUS
 NODE MCU
 DHT11 SENSOR
 WIRES
 LAPTOP
 USB CABLE
 ARDUINO IDE
 THINGSPEAK CLOUD

3.
BLOCK DIAGRAM
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4.
EXPLANATION OF BLOCK
DIAGRAM
 DHT11 is connected to the NODE MCU which is in turn connected to the
THINGSPEAK IOT CLOUD SERVER through the internet. We program the NODE
MCU through the Arduino IDE to post (publish) the data (temperature & humidity
data ) collected by the DHT11 Sensor on a channel created in the THINGSPEAK
CLOUD SERVER.
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5.
ABOUT
 NODE MCU : Node MCU is a low-cost open source IoT platform. It initially included
firmware which runs on the ESP8266, and hardware which was based on the ESP-12 module.
support for the ESP32 32-bit MCU was added.
 DHT11 : The DHT-11 Digital Temperature And Humidity Sensor is a basic, ultra low-cost
digital temperature and humidity sensor. It uses a capacitive humidity sensor and a thermistor to
measure the surrounding air and spits out a digital signal on the data pin (no analog input pins
needed).
 ARDUINO IDE : The Arduino Integrated Development Environment - or Arduino
Software (IDE) - contains a text editor for writing code, a message area, a text console, a toolbar
with buttons for common functions and a series of menus. It connects to the Arduino hardware to
upload programs and communicate with them.
 THINGSPEAK CLOUD : Thing Speak is an IoT analytics platform service that
allows you to aggregate, visualize and analyze live data streams in the cloud. Thing Speak
provides instant visualizations of data posted by your devices to Thing Speak.
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NODE MCU

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DHT11

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ARDUINO IDE

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THINGSPEAK CLOUD

10.
PROGRAMMING
#include <WiFiClient.h>;
#include <ESP8266WiFi.h>;
#include <ThingSpeak.h>;
#include <DHTesp.h>
#define DHTpin D3
const char ssid[] = "Subhodeep"; // your network SSID (name)
const char pass[] = "Dec@1995"; // your network password
DHTesp dht;
WiFiClient client;
unsigned long myChannelNumber =1385333;
const char * myWriteAPIKey = "1YHWW0GEDO03JHCH"; 10

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void setup()
{
Serial.begin(115200);
dht.setup(DHTpin,DHTesp::DHT11);
WiFi.begin(ssid,pass);
ThingSpeak.begin(client); // Initialize ThingSpeak
}
void loop()
{
float h = dht.getHumidity();
float t = dht.getTemperature();
// set the fields with the values
Serial.println(h);
Serial.println(t);

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ThingSpeak.setField(1, h);
ThingSpeak.setField(2, t);
ThingSpeak.writeFields(myChannelNumber, myWriteAPIKey);
delay(1000); // Wait 20 seconds to update the channel again
}

13.
RESULT
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