ArduinoESPHow ToSensorsTutorials/DIY

NodeMcu to DHT Interface in Blynk app

Hello Visitors, Today i show you how to interface DHT sensor Value in Blynk Apps use ESP8266 .

Things used in this project

DHT11 sensor measures and provides humidity and temperature values serially over a single wire. First read this article and prepare arduino for ESP8266 Arduino Support for ESP8266 with simple test code

PIN Connection:

pin connection

 

Create a Project use Blynk apps Following Instruction First LogIn your Blynk App Then Flow the Step By Step

NOTE – You got your AUTH TOKEN it send to your email address.

Now Flash this code in ESP8266. Here Replace SSID, SSID PASSWORD and Auth TOKEN. You need to Some library.

So Download by this link https://github.com/blynkkk/blynk-library/archive/master.zip

Adafruit DHT sensor libraries:
https://github.com/adafruit/Adafruit_Sensor
https://github.com/adafruit/DHT-sensor-library

Download these library and extract it. Now open Arduino and go to File>Properties. Here you find path of Arduino.

Now go to Arduino path and paste all extracted libraries folder in Libraries Folder. Select Board “Nodemcu 1.0” in Tool tab of Arduino IDE and Select right Port for Nodemcu. Now Flash this code given below.

Code

/*************************************************************

WARNING :
For this example you’ll need Adafruit DHT sensor libraries:
https://github.com/adafruit/Adafruit_Sensor
https://github.com/adafruit/DHT-sensor-library

App project setup:
Value Display widget attached to V5
Value Display widget attached to V6
*************************************************************/

/* Comment this out to disable prints and save space */
#define BLYNK_PRINT Serial
#include <ESP8266WiFi.h>
#include <BlynkSimpleEsp8266.h>
#include <DHT.h>

// You should get Auth Token in the Blynk App.
// Go to the Project Settings (nut icon).
char auth[] = “AUTH TOKEN”;      // replace with your auth token, You got your AUTH TOKEN it send to your email.

// Your WiFi credentials.
// Set password to “” for open networks.
char ssid[] = “YOUR SSID”;                                                                     // replace with your SSID
char pass[] = “SSID PASSWORD”;                                                          // SSID Password

#define DHTPIN 2 // What digital pin we’re connected to

// Uncomment whatever type you’re using!
#define DHTTYPE DHT11 // DHT 11
//#define DHTTYPE DHT22 // DHT 22, AM2302, AM2321
//#define DHTTYPE DHT21 // DHT 21, AM2301

DHT dht(DHTPIN, DHTTYPE);
BlynkTimer timer;

// This function sends Arduino’s up time every second to Virtual Pin (5).
// In the app, Widget’s reading frequency should be set to PUSH. This means
// that you define how often to send data to Blynk App.
void sendSensor()
{
float h = dht.readHumidity();
float t = dht.readTemperature(); // or dht.readTemperature(true) for Fahrenheit

if (isnan(h) || isnan(t)) {
Serial.println(“Failed to read from DHT sensor!”);
return;
}
// You can send any value at any time.
// Please don’t send more that 10 values per second.
Blynk.virtualWrite(V5, h);
Blynk.virtualWrite(V6, t);
}

void setup()
{
// Debug console
Serial.begin(9600);

Blynk.begin(auth, ssid, pass);
// You can also specify server:
//Blynk.begin(auth, ssid, pass, “blynk-cloud.com”, 80);
//Blynk.begin(auth, ssid, pass, IPAddress(192,168,1,100), 8080);

dht.begin();

// Setup a function to be called every second
timer.setInterval(1000L, sendSensor);
}

void loop()
{
Blynk.run();
timer.run();
}

Harshvardhan Mishra

Hi, I'm Harshvardhan Mishra. Tech enthusiast and IT professional with a B.Tech in IT, PG Diploma in IoT from CDAC, and 6 years of industry experience. Founder of HVM Smart Solutions, blending technology for real-world solutions. As a passionate technical author, I simplify complex concepts for diverse audiences. Let's connect and explore the tech world together! If you want to help support me on my journey, consider sharing my articles, or Buy me a Coffee! Thank you for reading my blog! Happy learning! Linkedin

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