alex9ufo 聰明人求知心切: 新實驗1-2 ESP32 + RFID + MQTT Explorer + Node-Red (控制LED 顯示RFID 卡號)

新實驗1-2 ESP32 + RFID + MQTT Explorer + Node-Red (控制LED 顯示RFID 卡號)
#include <WiFi.h>
#include <PubSubClient.h>
#include <SPI.h>
#include <MFRC522.h>
// GPIO 2 D1
#define LED 2
/* Wiring RFID RC522 module
=============================================================================
GND     = GND   3.3V    = 3.3V
The following table shows the typical pin layout used:
 *             MFRC522      ESP32     Arduino       Arduino   Arduino    Arduino          Arduino
 *             Reader/PCD             Uno/101       Mega      Nano v3    Leonardo/Micro   Pro Micro
 * Signal      Pin          Pin       Pin           Pin       Pin        Pin              Pin
 * -----------------------------------------------------------------------------------------
 * RST/Reset   RST          GPIO27    9             5         D9         RESET/ICSP-5     RST
 * SPI SS      SDA(SS)      GPIO5     10            53        D10        10               10
 * SPI MOSI    MOSI         GPIO23    11 / ICSP-4   51        D11        ICSP-4           16
 * SPI MISO    MISO         GPIO19    12 / ICSP-1   50        D12        ICSP-1           14
 * SPI SCK     SCK          GPIO18    13 / ICSP-3   52        D13        ICSP-3           15
 *
[1] (1, 2) Configurable, typically defined as RST_PIN in sketch/program.
[2] (1, 2) Configurable, typically defined as SS_PIN in sketch/program.
[3] The SDA pin might be labeled SS on some/older MFRC522 boards
=============================================================================
*/

#define SS_PIN  5  // ESP32 pin GIOP5 
#define RST_PIN 27 // ESP32 pin GIOP27 


// WiFi
const char *ssid = "alex9ufo"; // Enter your Wi-Fi name
const char *password = "alex9981";  // Enter Wi-Fi password

// MQTT Broker
const char *mqtt_broker = "broker.mqtt-dashboard.com";
const char *topic1 = "alex9ufo/esp32/led";
const char *topic2 = "alex9ufo/esp32/RFID";

const char *mqtt_username = "alex9ufo";
const char *mqtt_password = "public";
const int mqtt_port = 1883;

bool ledState = false;

WiFiClient espClient;
PubSubClient client(espClient);
MFRC522 rfid(SS_PIN, RST_PIN); // Create MFRC522 instance

long lastMsg = 0;
char msg[50];
String json = "";    
char jsonChar1[100];  //client.publish("alex9ufo/Esp32/RFID"
//===========================================================
String printHex(byte *buffer, byte bufferSize) {
      String id = "";
      for (byte i = 0; i < bufferSize; i++) {
        id += buffer[i] < 0x10 ? "0" : "";
        id += String(buffer[i], HEX);
      }
      return id;
    }
//===========================================================
void setup() {
    // Set software serial baud to 115200;
    Serial.begin(115200);
    delay(1000); // Delay for stability
    //======================================================
    // Connecting to a WiFi network
    WiFi.begin(ssid, password);
    while (WiFi.status() != WL_CONNECTED) {
        delay(500);
        Serial.println("Connecting to WiFi...");
    }
    Serial.println("Connected to the WiFi network");

    // Setting LED pin as output
    pinMode(LED, OUTPUT);
    digitalWrite(LED, LOW);  // Turn off the LED initially
    //======================================================
    SPI.begin();           // Init SPI bus
    rfid.PCD_Init();    // Init MFRC522

    Serial.println(F("Ready!"));
    Serial.println(F("======================================================")); 
    Serial.println("Tap an RFID/NFC tag on the RFID-RC522 reader");


    // Connecting to an MQTT broker
    client.setServer(mqtt_broker, mqtt_port);
    client.setCallback(callback);
    while (!client.connected()) {
        String client_id = "esp32-client-";
        client_id += String(WiFi.macAddress());
        Serial.printf("The client %s connects to the public MQTT broker\n", client_id.c_str());
        if (client.connect(client_id.c_str(), mqtt_username, mqtt_password)) {
            Serial.println("Public HiveMQ MQTT broker (broker.mqtt-dashboard.com) connected");
        } else {
            Serial.print("Failed with state ");
            Serial.print(client.state());
            delay(2000);
        }
    }

    // Publish and subscribe
    client.subscribe(topic1);

}
//===========================================================
void callback(char *topic, byte *payload, unsigned int length) {
    Serial.print("Message arrived in topic: ");
    Serial.println(topic);
    Serial.print("Message: ");
    String message;
    for (int i = 0; i < length; i++) {
        message += (char) payload[i];  // Convert *byte to string
    }
    Serial.print(message);
    if (message == "on" && !ledState) {
        digitalWrite(LED, HIGH);  // Turn on the LED
        ledState = true;
    }
    if (message == "off" && ledState) {
        digitalWrite(LED, LOW); // Turn off the LED
        ledState = false;
    }
    Serial.println();
    Serial.println("-----------------------");
}
//===========================================================
void loop() {
    client.loop();
    delay(100); // Delay for a short period in each loop iteration
    long now = millis();
    if (now - lastMsg > 5000) {
      Serial.println("Reading RFIF card");
      lastMsg = now;
      if (rfid.PICC_IsNewCardPresent()) { // new tag is available
        if (rfid.PICC_ReadCardSerial()) { // NUID has been readed
          MFRC522::PICC_Type piccType = rfid.PICC_GetType(rfid.uid.sak);
          Serial.print("RFID/NFC Tag Type: ");
          Serial.println(rfid.PICC_GetTypeName(piccType));

          // print UID in Serial Monitor in the hex format
          Serial.print("UID:");
          for (int i = 0; i < rfid.uid.size; i++) {
            Serial.print(rfid.uid.uidByte[i] < 0x10 ? " 0" : " ");
            Serial.print(rfid.uid.uidByte[i], HEX);
          }
          Serial.println();

          String json = printHex(rfid.uid.uidByte, rfid.uid.size);
          // Convert JSON string to character array
          json.toCharArray(jsonChar1, json.length()+1);
    
          if  (client.connected()) {
            Serial.print("Publish message: ");
            Serial.println(json);
            // Publish JSON character array to MQTT topic
            client.publish(topic2,jsonChar1);
          }     
          rfid.PICC_HaltA(); // halt PICC
          rfid.PCD_StopCrypto1(); // stop encryption on PCD

        }
      }
        
  }

}
//===========================================================