Nodemcu ve LCD ile web sitesindeki online sayacı

readme.md

LCD -> NODEMCU / POTANSIYOMETRE

VSS -> GND

VDD -> 3.3V

V0 -> POTANSIYOMETRE DATA (ORTA PİN)

RS -> D1

RV -> GND

E -> D2

D4 -> D3

D5 -> D4 

D6 -> D5

D7 -> D6

A -> 3.3V

K -> GND

NOTE:

Potansiyometre sağ bacak GND

Potansiyometre sağ bacak 3.3V

backend.js

const io = require('socket.io')()

let user = 0

io.on('connection', socket => {

  ++user

  console.log('Someone connected');
  io.sockets.emit('event', `${user} Online`)


  socket.on('disconnect', function () {
    --user
    io.sockets.emit('event', `${user} Online`)
  })
})

io.listen(process.env.PORT || 3000)

nodemcu.ino

#include <ESP8266WiFi.h>
#include <ESP8266WiFiMulti.h>

#include <SocketIoClient.h>

#define USE_SERIAL Serial
#include <LiquidCrystal.h>;

ESP8266WiFiMulti WiFiMulti;
SocketIoClient webSocket;

LiquidCrystal lcd(5, 4, 0, 2, 14, 12);
void event(const char * payload, size_t length) {
  USE_SERIAL.printf("got message: %s\n", payload);
    
    lcd.setCursor(3, 0);
    lcd.print(payload);
    lcd.setCursor(3, 1);
    lcd.print("Ders.im");
}

void setup() {
    USE_SERIAL.begin(115200);
    lcd.begin(16, 2);
    USE_SERIAL.setDebugOutput(true);

    USE_SERIAL.println();
    USE_SERIAL.println();
    USE_SERIAL.println();

      for(uint8_t t = 4; t > 0; t--) {
          USE_SERIAL.printf("[SETUP] BOOT WAIT %d...\n", t);
          USE_SERIAL.flush();
          delay(1000);
      }

    WiFiMulti.addAP("brsesen", "12345678");

    while(WiFiMulti.run() != WL_CONNECTED) {
        delay(100);
    }

    webSocket.on("event", event);
    webSocket.begin("192.168.43.161", 3000, "/socket.io/?transport=websocket");
}

void loop() { 
    webSocket.loop();
}

https://github.com/timum-viw/socket.io-client
kullanılan paket bu, burdaki adımları yapmamız lazım