UdpSendReceive.ino

/****************************************************************************************************************************
  UDPSendReceive.ino - Simple Arduino web server sample for ESP8266/ESP32 AT-command shield

  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
 *****************************************************************************************************************************/
/*
   The Arduino board communicates with the shield using the SPI bus. This is on digital pins 11, 12, and 13 on the Uno
   and pins 50, 51, and 52 on the Mega. On both boards, pin 10 is used as SS. On the Mega, the hardware SS pin, 53,
   is not used to select the Ethernet controller chip, but it must be kept as an output or the SPI interface won't work.
*/

#include "defines.h"

unsigned int localPort = 1883;    //10002;  // local port to listen on

char packetBuffer[255];          // buffer to hold incoming packet
char ReplyBuffer[] = "ACK";      // a string to send back

// A UDP instance to let us send and receive packets over UDP
EthernetUDP Udp;

void setup()
{
  Serial.begin(115200);

  while (!Serial);

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

#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)

#if (USING_SPI2)
#if defined(CUR_PIN_MISO)
  ET_LOGWARN(F("Default SPI pinout:"));
  ET_LOGWARN1(F("MOSI:"), CUR_PIN_MOSI);
  ET_LOGWARN1(F("MISO:"), CUR_PIN_MISO);
  ET_LOGWARN1(F("SCK:"),  CUR_PIN_SCK);
  ET_LOGWARN1(F("SS:"),   CUR_PIN_SS);
  ET_LOGWARN(F("========================="));
#endif
#else
  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("========================="));
#endif

#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
  // EthernetGeneric    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_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_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);

#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)

  // 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)
  ET_LOGWARN(F("========================="));

#if defined( ESP32 )
  // Just info to know how to connect correctly
  // To change for other SPI
  ET_LOGWARN(F("Currently Used SPI pinout:"));
  ET_LOGWARN1(F("MOSI:"), PIN_MOSI);
  ET_LOGWARN1(F("MISO:"), PIN_MISO);
  ET_LOGWARN1(F("SCK:"),  PIN_SCK);
  ET_LOGWARN1(F("SS:"),   PIN_SS);
#else
#if defined(CUR_PIN_MISO)
  ET_LOGWARN(F("Currently Used SPI pinout:"));
  ET_LOGWARN1(F("MOSI:"), CUR_PIN_MOSI);
  ET_LOGWARN1(F("MISO:"), CUR_PIN_MISO);
  ET_LOGWARN1(F("SCK:"),  CUR_PIN_SCK);
  ET_LOGWARN1(F("SS:"),   CUR_PIN_SS);
#else
  ET_LOGWARN(F("Currently Used SPI pinout:"));
  ET_LOGWARN1(F("MOSI:"), MOSI);
  ET_LOGWARN1(F("MISO:"), MISO);
  ET_LOGWARN1(F("SCK:"),  SCK);
  ET_LOGWARN1(F("SS:"),   SS);
#endif
#endif

  ET_LOGWARN(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());

  Serial.println(F("\nStarting connection to server..."));
  // if you get a connection, report back via serial:
  Udp.begin(localPort);

  Serial.print(F("Listening on port "));
  Serial.println(localPort);
}

void loop()
{
  // if there's data available, read a packet
  int packetSize = Udp.parsePacket();

  if (packetSize)
  {
    Serial.print(F("Received packet of size "));
    Serial.println(packetSize);
    Serial.print(F("From "));
    IPAddress remoteIp = Udp.remoteIP();
    Serial.print(remoteIp);
    Serial.print(F(", port "));
    Serial.println(Udp.remotePort());

    // read the packet into packetBufffer
    int len = Udp.read(packetBuffer, 255);

    if (len > 0)
    {
      packetBuffer[len] = 0;
    }

    Serial.println(F("Contents:"));
    Serial.println(packetBuffer);

    // send a reply, to the IP address and port that sent us the packet we received
    Udp.beginPacket(Udp.remoteIP(), Udp.remotePort());
    Udp.write(ReplyBuffer);
    Udp.endPacket();
  }
}