MQTTClient_Basic.ino

/****************************************************************************************************************************
  MQTTClient_Basic.ino - Dead simple MQTT Client for Ethernet shields

  EthernetWebServer is a library for the Ethernet shields to run WebServer
  
  Based on and modified from ESP8266 https://github.com/esp8266/Arduino/releases
  Built by Khoi Hoang https://github.com/khoih-prog/EthernetWebServer
  Licensed under MIT license
 *****************************************************************************************************************************/

/*
  Basic MQTT example (without SSL!) with Authentication
  This sketch demonstrates the basic capabilities of the library.
  It connects to an MQTT server then:
  - providing username and password
  - publishes "hello world" to the topic "outTopic"
  - subscribes to the topic "inTopic", printing out any messages
    it receives. NB - it assumes the received payloads are strings not binary
    
  It will reconnect to the server if the connection is lost using a blocking
  reconnect function. See the 'mqtt_reconnect_nonblocking' example for how to
  achieve the same result without blocking the main loop.
*/

#include "defines.h"

#include <PubSubClient.h>

// Update these with values suitable for your network.
//const char* mqttServer = "broker.example";        // Broker address
const char* mqttServer = "broker.emqx.io";        // Broker address

const char *ID        = "MQTTClient_SSL-Client";  // Name of our device, must be unique
const char *TOPIC     = "MQTT_Pub";               // Topic to subcribe to
const char *subTopic  = "MQTT_Sub";               // Topic to subcribe to

//IPAddress mqttServer(172, 16, 0, 2);

void callback(char* topic, byte* payload, unsigned int length) 
{
  Serial.print("Message arrived [");
  Serial.print(topic);
  Serial.print("] ");
  
  for (unsigned int i = 0; i < length; i++) 
  {
    Serial.print((char)payload[i]);
  }
  
  Serial.println();
}

EthernetClient  ethClient;
PubSubClient    client(mqttServer, 1883, callback, ethClient);

void reconnect()
{
  // Loop until we're reconnected
  while (!client.connected())
  {
    Serial.print("Attempting MQTT connection to ");
    Serial.print(mqttServer);

    // Attempt to connect
    if (client.connect(ID, "try", "try"))
    {
      Serial.println("...connected");
      
      // Once connected, publish an announcement...
      String data = "Hello from MQTTClient_SSL on " + String(BOARD_NAME);

      client.publish(TOPIC, data.c_str());

      //Serial.println("Published connection message successfully!");
      //Serial.print("Subcribed to: ");
      //Serial.println(subTopic);
      
      // ... and resubscribe
      client.subscribe(subTopic);
      // for loopback testing
      client.subscribe(TOPIC);
    }
    else
    {
      Serial.print("...failed, rc=");
      Serial.print(client.state());
      Serial.println(" try again in 5 seconds");

      // Wait 5 seconds before retrying
      delay(5000);
    }
  }
}

void setup()
{
  // Open serial communications and wait for port to open:
  Serial.begin(115200);
  while (!Serial);

  Serial.print("\nStart MQTTClient_Basic on "); Serial.print(BOARD_NAME);
  Serial.print(F(" with ")); Serial.println(SHIELD_TYPE); 
  Serial.println(ETHERNET_WEBSERVER_VERSION);

#if USE_ETHERNET_WRAPPER

  EthernetInit();

#else

#if USE_ETHERNET_PORTENTA_H7
  ET_LOGWARN(F("======== USE_PORTENTA_H7_ETHERNET ========"));
#elif USE_NATIVE_ETHERNET
  ET_LOGWARN(F("======== USE_NATIVE_ETHERNET ========"));
#elif USE_ETHERNET_GENERIC
  ET_LOGWARN(F("=========== USE_ETHERNET_GENERIC ==========="));  
#elif USE_ETHERNET_ESP8266
  ET_LOGWARN(F("=========== USE_ETHERNET_ESP8266 ==========="));
#elif USE_ETHERNET_ENC
  ET_LOGWARN(F("=========== USE_ETHERNET_ENC ==========="));  
#else
  ET_LOGWARN(F("========================="));
#endif

#if !(USE_NATIVE_ETHERNET || USE_ETHERNET_PORTENTA_H7)
  ET_LOGWARN(F("Default SPI pinout:"));
  ET_LOGWARN1(F("MOSI:"), MOSI);
  ET_LOGWARN1(F("MISO:"), MISO);
  ET_LOGWARN1(F("SCK:"),  SCK);
  ET_LOGWARN1(F("SS:"),   SS);
  ET_LOGWARN(F("========================="));

#if defined(ESP8266)
  // For ESP8266, change for other boards if necessary
  #ifndef USE_THIS_SS_PIN
    #define USE_THIS_SS_PIN   D2    // For ESP8266
  #endif

  ET_LOGWARN1(F("ESP8266 setCsPin:"), USE_THIS_SS_PIN);

  #if ( USE_ETHERNET_GENERIC || USE_ETHERNET_ENC )
    // For ESP8266
    // Pin                D0(GPIO16)    D1(GPIO5)    D2(GPIO4)    D3(GPIO0)    D4(GPIO2)    D8
    // Ethernet           0                 X            X            X            X        0
    // Ethernet2          X                 X            X            X            X        0
    // Ethernet3          X                 X            X            X            X        0
    // EthernetLarge      X                 X            X            X            X        0
    // Ethernet_ESP8266   0                 0            0            0            0        0
    // D2 is safe to used for Ethernet, Ethernet2, Ethernet3, EthernetLarge libs
    // Must use library patch for Ethernet, EthernetLarge libraries
    Ethernet.init (USE_THIS_SS_PIN);

  #elif USE_ETHERNET3
    // Use  MAX_SOCK_NUM = 4 for 4K, 2 for 8K, 1 for 16K RX/TX buffer
    #ifndef ETHERNET3_MAX_SOCK_NUM
      #define ETHERNET3_MAX_SOCK_NUM      4
    #endif
  
    Ethernet.setCsPin (USE_THIS_SS_PIN);
    Ethernet.init (ETHERNET3_MAX_SOCK_NUM);

  #elif USE_CUSTOM_ETHERNET
  
    // You have to add initialization for your Custom Ethernet here
    // This is just an example to setCSPin to USE_THIS_SS_PIN, and can be not correct and enough
    Ethernet.init(USE_THIS_SS_PIN);
  
  #endif  //( USE_ETHERNET_GENERIC || USE_ETHERNET_ENC )

#elif defined(ESP32)

  // You can use Ethernet.init(pin) to configure the CS pin
  //Ethernet.init(10);  // Most Arduino shields
  //Ethernet.init(5);   // MKR ETH shield
  //Ethernet.init(0);   // Teensy 2.0
  //Ethernet.init(20);  // Teensy++ 2.0
  //Ethernet.init(15);  // ESP8266 with Adafruit Featherwing Ethernet
  //Ethernet.init(33);  // ESP32 with Adafruit Featherwing Ethernet

  #ifndef USE_THIS_SS_PIN
    #define USE_THIS_SS_PIN   5   //22    // For ESP32
  #endif

  ET_LOGWARN1(F("ESP32 setCsPin:"), USE_THIS_SS_PIN);

  // For other boards, to change if necessary
  #if ( USE_ETHERNET_GENERIC || USE_ETHERNET_ENC )
    // Must use library patch for Ethernet, EthernetLarge libraries
    // ESP32 => GPIO2,4,5,13,15,21,22 OK with Ethernet, Ethernet2, EthernetLarge
    // ESP32 => GPIO2,4,5,15,21,22 OK with Ethernet3
  
    //Ethernet.setCsPin (USE_THIS_SS_PIN);
    Ethernet.init (USE_THIS_SS_PIN);
  
  #elif USE_ETHERNET3
    // Use  MAX_SOCK_NUM = 4 for 4K, 2 for 8K, 1 for 16K RX/TX buffer
    #ifndef ETHERNET3_MAX_SOCK_NUM
      #define ETHERNET3_MAX_SOCK_NUM      4
    #endif
  
    Ethernet.setCsPin (USE_THIS_SS_PIN);
    Ethernet.init (ETHERNET3_MAX_SOCK_NUM);

  #elif USE_CUSTOM_ETHERNET
  
    // You have to add initialization for your Custom Ethernet here
    // This is just an example to setCSPin to USE_THIS_SS_PIN, and can be not correct and enough
    Ethernet.init(USE_THIS_SS_PIN); 
  
  #endif  //( USE_ETHERNET_GENERIC || USE_ETHERNET_ENC )

#elif ETHERNET_USE_RPIPICO

  pinMode(USE_THIS_SS_PIN, OUTPUT);
  digitalWrite(USE_THIS_SS_PIN, HIGH);
  
  // ETHERNET_USE_RPIPICO, use default SS = 5 or 17
  #ifndef USE_THIS_SS_PIN
    #if defined(ARDUINO_ARCH_MBED)
      #define USE_THIS_SS_PIN   5     // For Arduino Mbed core
    #else  
      #define USE_THIS_SS_PIN   17    // For E.Philhower core
    #endif
  #endif

  ET_LOGWARN1(F("RPIPICO setCsPin:"), USE_THIS_SS_PIN);

  // For other boards, to change if necessary
  #if ( USE_ETHERNET_GENERIC || USE_ETHERNET_ENC )
    // Must use library patch for Ethernet, EthernetLarge libraries
    // For RPI Pico using Arduino Mbed RP2040 core
    // SCK: GPIO2,  MOSI: GPIO3, MISO: GPIO4, SS/CS: GPIO5
    // For RPI Pico using E. Philhower RP2040 core
    // SCK: GPIO18,  MOSI: GPIO19, MISO: GPIO16, SS/CS: GPIO17
    // Default pin 5/17 to SS/CS
  
    //Ethernet.setCsPin (USE_THIS_SS_PIN);
    Ethernet.init (USE_THIS_SS_PIN);
  
  #elif USE_ETHERNET3
    // Use  MAX_SOCK_NUM = 4 for 4K, 2 for 8K, 1 for 16K RX/TX buffer
    #ifndef ETHERNET3_MAX_SOCK_NUM
      #define ETHERNET3_MAX_SOCK_NUM      4
    #endif
  
    Ethernet.setCsPin (USE_THIS_SS_PIN);
    Ethernet.init (ETHERNET3_MAX_SOCK_NUM);
    
  #endif    //( USE_ETHERNET_GENERIC || USE_ETHERNET_ENC )

#else   //defined(ESP8266)
  // unknown board, do nothing, use default SS = 10
  #ifndef USE_THIS_SS_PIN
    #define USE_THIS_SS_PIN   10    // For other boards
  #endif

  #if defined(BOARD_NAME)
    ET_LOGWARN3(F("Board :"), BOARD_NAME, F(", setCsPin:"), USE_THIS_SS_PIN);
  #else
    ET_LOGWARN1(F("Unknown board setCsPin:"), USE_THIS_SS_PIN);
  #endif

  // For other boards, to change if necessary
  #if ( USE_ETHERNET_GENERIC || USE_ETHERNET_ENC || USE_NATIVE_ETHERNET )
    // Must use library patch for Ethernet, Ethernet2, EthernetLarge libraries
  
    Ethernet.init (USE_THIS_SS_PIN);
  
  #elif USE_CUSTOM_ETHERNET
  
    // You have to add initialization for your Custom Ethernet here
    // This is just an example to setCSPin to USE_THIS_SS_PIN, and can be not correct and enough
    Ethernet.init(USE_THIS_SS_PIN);
    
  #endif  //( USE_ETHERNET_GENERIC || USE_ETHERNET_ENC )

#endif    // defined(ESP8266)

#endif    // #if !(USE_NATIVE_ETHERNET)


#endif  //USE_ETHERNET_WRAPPER


  // start the ethernet connection and the server:
  // Use DHCP dynamic IP and random mac
  uint16_t index = millis() % NUMBER_OF_MAC;
  // Use Static IP
  //Ethernet.begin(mac[index], ip);
  Ethernet.begin(mac[index]);

#if !(USE_NATIVE_ETHERNET || USE_ETHERNET_PORTENTA_H7)
  #if defined( ESP32 )
    // Just info to know how to connect correctly
    // To change for other SPI
    Serial.println("=========================");
    Serial.println("Currently Used SPI pinout:");
    Serial.print("MOSI:");
    Serial.println(PIN_MOSI);
    Serial.print("MISO:");
    Serial.println(PIN_MISO);
    Serial.print("SCK:");
    Serial.println(PIN_SCK);
    Serial.print("SS:");
    Serial.println(USE_THIS_SS_PIN);
    Serial.println(F("========================="));
  #else
    // Just info to know how to connect correctly
    Serial.println("=========================");
    Serial.println("Currently Used SPI pinout:");
    Serial.print("MOSI:");
    Serial.println(MOSI);
    Serial.print("MISO:");
    Serial.println(MISO);
    Serial.print("SCK:");
    Serial.println(SCK);
    Serial.print("SS:");
    Serial.println(SS);
  #endif
  
  Serial.println(F("========================="));

#elif (USE_ETHERNET_PORTENTA_H7)
  if (Ethernet.hardwareStatus() == EthernetNoHardware) 
  {
    Serial.println("No Ethernet found. Stay here forever");
    
    while (true) 
    {
      delay(1); // do nothing, no point running without Ethernet hardware
    }
  }
  
  if (Ethernet.linkStatus() == LinkOFF) 
  {
    Serial.println("Not connected Ethernet cable");
  }
#endif

  Serial.print(F("Using mac index = "));
  Serial.println(index);

  Serial.print(F("Connected! IP address: "));
  Serial.println(Ethernet.localIP());

  client.setServer(mqttServer, 1883);
  client.setCallback(callback);

  // Allow the hardware to sort itself out
  delay(1500);
}

#define MQTT_PUBLISH_INTERVAL_MS       5000L

String data         = "Hello from MQTTClient_Basic on " + String(BOARD_NAME) + " with " + String(SHIELD_TYPE);
const char *pubData = data.c_str();

unsigned long lastMsg = 0;

void loop() 
{
  static unsigned long now;
  
  if (!client.connected()) 
  {
    reconnect();
  }

  // Sending Data
  now = millis();
  
  if (now - lastMsg > MQTT_PUBLISH_INTERVAL_MS)
  {
    lastMsg = now;

    if (!client.publish(TOPIC, pubData))
    {
      Serial.println("Message failed to send.");
    }

    Serial.print("Message Send : " + String(TOPIC) + " => ");
    Serial.println(data);
  }
  
  client.loop();
}