Tasnim Zotder
Published © MIT

Room Automation w/ Blynk

DIY room appliances control over the cloud

IntermediateWork in progress2.5 hours998
Room Automation w/ Blynk

Things used in this project

Hardware components

NodeMCU ESP8266 Breakout Board
NodeMCU ESP8266 Breakout Board
×1
Solderless Breadboard Half Size
Solderless Breadboard Half Size
×1
4-CHANNEL RELAY CONTROLLER FOR I2C
ControlEverything.com 4-CHANNEL RELAY CONTROLLER FOR I2C
×1
Jumper wires (generic)
Jumper wires (generic)
×1

Software apps and online services

Arduino IDE
Arduino IDE
VS Code
Microsoft VS Code
PlatformIO IDE
PlatformIO IDE
Blynk
Blynk

Hand tools and fabrication machines

Hot glue gun (generic)
Hot glue gun (generic)

Story

Read more

Schematics

Schematic

schematic

Schematic Diagram

Breadboard Diagram

PCB Diagram

Code

main.cpp

C/C++
#include <BlynkSimpleEsp8266.h>
#include <DHT.h>
#include <ESP8266WiFi.h>

#include "credentials.h"

/* 
____ file    'credentials.h' ____

#define SEC_AUTH "abc123"   // auth credential from Blynk app
#define SEC_SSID "abc123"   // wifi ssid
#define SEC_PASS "abc123"   // wifi password

*/

char auth[] = SEC_AUTH;      // alternate -> char auth[] = "abc123"

char ssid[] = SEC_SSID;      // alternate -> char ssid[] = "abc123"
char pass[] = SEC_PASS;      // alternate -> char pass[] = "abc123"

#define dhtType DHT11

// Define relay pins
#define relay1 D1
#define relay2 D3
#define relay3 D6
#define relay4 D7

// define dht pin
#define dhtPin D2

DHT dht(dhtPin, dhtType);

/*
 -> Virtual Pins

  * V1 - LED 1
  * V2 - LED 2
  * V3 - LED 3
  * V4 - LED 4

  * V10 - Btn 1
  * V11 - Btn 2
  * V12 - Btn 3
  * V13 - Btn 4

  * V6 - Device Stats
  * V20 - Temp
  * V21 - Humidity
*/

// LED pins on Blynk app
WidgetLED led1(V1);
WidgetLED led2(V2);
WidgetLED led3(V3);
WidgetLED led4(V4);

// LED states
int led1_state = 0;
int led2_state = 0;
int led3_state = 0;
int led4_state = 0;

// count of total active (turned on) LEDs
int total_led;

BlynkTimer timer;

BLYNK_WRITE(V10) {
    int pinValue = param.asInt();

    if (pinValue == 1) {
        digitalWrite(relay1, 1);
        led1.on();
        led1_state = 1;
    } else {
        digitalWrite(relay1, 0);
        led1.off();
        led1_state = 0;
    }
}

BLYNK_WRITE(V11) {
    int pinValue = param.asInt();

    if (pinValue == 1) {
        digitalWrite(relay2, 1);
        led2.on();
        led2_state = 1;
    } else {
        digitalWrite(relay2, 0);
        led2.off();
        led2_state = 0;
    }
}

BLYNK_WRITE(V12) {
    int pinValue = param.asInt();

    if (pinValue == 1) {
        digitalWrite(relay3, 1);
        led3.on();
        led3_state = 1;
    } else {
        digitalWrite(relay3, 0);
        led3.off();
        led3_state = 0;
    }
}

BLYNK_WRITE(V13) {
    int pinValue = param.asInt();

    if (pinValue == 1) {
        digitalWrite(relay4, 1);
        led4.on();
        led4_state = 1;
    } else {
        digitalWrite(relay4, 0);
        led4.off();
        led4_state = 0;
    }
}

void getDhtValues() {
    // delay(2000);
    float h = dht.readHumidity();         // humidity
    float t = dht.readTemperature();      // temp (Celcius)

    if (isnan(h) || isnan(t)) {
        Serial.println("Failed to read from DHT sensor!");
        return;
    }

    Blynk.virtualWrite(V20, t);
    Blynk.virtualWrite(V21, h);

    Serial.print("Humidity: ");
    Serial.print(h);
    Serial.print(" \t");
    Serial.print("Temp: ");
    Serial.println(t);
}

void setup() {
    Serial.begin(115200);
    Serial.println("Tasnim's Home Automation");
    Blynk.begin(auth, ssid, pass);
    dht.begin();

    pinMode(relay1, OUTPUT);
    pinMode(relay2, OUTPUT);
    pinMode(relay3, OUTPUT);
    pinMode(relay4, OUTPUT);

    timer.setInterval(10000L, getDhtValues);
}

void loop() {
    Blynk.run();
    timer.run();
    total_led = led1_state + led2_state + led3_state + led4_state;
    Blynk.virtualWrite(V6, total_led);
}

Github

https://github.com/tasnimzotder/room_automation_w_blynk

Credits

Tasnim Zotder

Tasnim Zotder

4 projects • 2 followers

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