ESP8266 อ่านค่าอุณหภูมิ ความชื้น จาก DHT22 แสดงในแอป Blynk

 ESP8266 อ่านค่าอุณหภูมิ ความชื้น จาก DHT22 แสดงในแอป Blynk

การเชื่อมต่อ

ESP8266 -> Sensor DHT22 วัดอุณหภูมิและความชื้น

3V         -> ขา+

GND        -> ขา-

D4(GPIO 2) -> ขาOUT

วิธีทำ 

1.Quick Start สร้าง Template  เชื่อมต่อแอป Blynk กับ ESP8266

2.เขียนโคด้ เชื่อมต่อ บอร์ด ESP8266 and DHT22

3.สร้าง Datastream in Blynk

4.สร้าง Web Dashboard in Blynk

5.เขียนโค้ด ให้ทำงานร่วมกับ และส่งค่าด้วยคำสั่ง

Blynk.virtualWrite(Virtualpin0, ตัวแปร1);//h,t,f,hic,hif

Blynk.virtualWrite(Virtualpin1, ตัวแปร2);

6.ลบโค้ดส่วนที่ไม่ใช้งานออกไป 

#include "DHT.h"

#define DHTPIN 2     // Digital pin connected to the DHT sensor

#define DHTTYPE DHT22   // DHT 22  (AM2302), AM2321

DHT dht(DHTPIN, DHTTYPE);

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

  This is a simple demo of sending and receiving some data.

  Be sure to check out other examples!

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

/* Fill-in information from Blynk Device Info here */

#define BLYNK_TEMPLATE_ID           "TMPL6wMZTx-cb"

#define BLYNK_TEMPLATE_NAME         "Quickstart Template"

#define BLYNK_AUTH_TOKEN            "mnhX72ZXaX1WN5gPgft3wUdsqJOOxlrc"

/* Comment this out to disable prints and save space */

#define BLYNK_PRINT Serial

#include <ESP8266WiFi.h>

#include <BlynkSimpleEsp8266.h>

// Your WiFi credentials.

// Set password to "" for open networks.

char ssid[] = "ใส่ชื่อ wifi 2.4 ghz";

char pass[] = "ใส่รหัสผ่าน wifi";

BlynkTimer timer;

// This function is called every time the Virtual Pin 0 state changes

BLYNK_WRITE(V0)

{

  // Set incoming value from pin V0 to a variable

  int value = param.asInt();

  // Update state

  Blynk.virtualWrite(V1, value);

}

// This function is called every time the device is connected to the Blynk.Cloud

BLYNK_CONNECTED()

{

  // Change Web Link Button message to "Congratulations!"

  Blynk.setProperty(V3, "offImageUrl", "https://static-image.nyc3.cdn.digitaloceanspaces.com/general/fte/congratulations.png");

  Blynk.setProperty(V3, "onImageUrl",  "https://static-image.nyc3.cdn.digitaloceanspaces.com/general/fte/congratulations_pressed.png");

  Blynk.setProperty(V3, "url", "https://docs.blynk.io/en/getting-started/what-do-i-need-to-blynk/how-quickstart-device-was-made");

}

// This function sends Arduino's uptime every second to Virtual Pin 2.

void myTimerEvent()

{

  // You can send any value at any time.

  // Please don't send more that 10 values per second.

  Blynk.virtualWrite(V2, millis() / 1000);

}

void setup()

{

  // Debug console

  Serial.begin(115200);

  Blynk.begin(BLYNK_AUTH_TOKEN, ssid, pass);

  // You can also specify server:

  //Blynk.begin(BLYNK_AUTH_TOKEN, ssid, pass, "blynk.cloud", 80);

  //Blynk.begin(BLYNK_AUTH_TOKEN, ssid, pass, IPAddress(192,168,1,100), 8080);

  // Setup a function to be called every second

  timer.setInterval(1000L, myTimerEvent);

  Serial.begin(9600);

  Serial.println(F("DHTxx test!"));

  dht.begin();

}

void loop()

{

  Blynk.run();

  timer.run();

  // You can inject your own code or combine it with other sketches.

  // Check other examples on how to communicate with Blynk. Remember

  // to avoid delay() function!

  float h = dht.readHumidity();

  // Read temperature as Celsius (the default)

  float t = dht.readTemperature();

  // Read temperature as Fahrenheit (isFahrenheit = true)

  float f = dht.readTemperature(true);

  // Check if any reads failed and exit early (to try again).

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

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

    return;

  }

  // Compute heat index in Fahrenheit (the default)

  float hif = dht.computeHeatIndex(f, h);

  // Compute heat index in Celsius (isFahreheit = false)

  float hic = dht.computeHeatIndex(t, h, false);  

  Serial.print(F("Humidity: "));

  Serial.print(h);

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

  Serial.print(t);

  Serial.print(F("°C "));

  Serial.print(f);

  Serial.print(F("°F  Heat index: "));

  Serial.print(hic);

  Serial.print(F("°C "));

  Serial.print(hif);

  Serial.println(F("°F"));  

  delay(2000);

  Blynk.virtualWrite(V0, t);

  Blynk.virtualWrite(V1, f);  

  Blynk.virtualWrite(V3, h);    

}

Relate Link :

Contact:

https://www.facebook.com/chaiyutpong