IPAddress ip(192, 168, 1, 177);

unsigned int localPort = 8888; // local port to listen on

// buffers for receiving and sending data char packetBuffer[UDP_TX_PACKET_MAX_SIZE]; // buffer to hold incoming packet, char ReplyBuffer[] = "acknowledged"; // a string to send back

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

void setup() { // 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

// start the Ethernet Ethernet.begin(mac, ip);

// Open serial communications and wait for port to open: Serial.begin(9600); while (!Serial) { ; // wait for serial port to connect. Needed for native USB port only }

// Check for Ethernet hardware present if (Ethernet.hardwareStatus() == EthernetNoHardware) { Serial.println("Ethernet shield was not found. Sorry, can't run without hardware. :("); while (true) { delay(1); // do nothing, no point running without Ethernet hardware } } if (Ethernet.linkStatus() == LinkOFF) { Serial.println("Ethernet cable is not connected."); }

// start UDP Udp.begin(localPort); }

void loop() { // if there's data available, read a packet int packetSize = Udp.parsePacket(); if (packetSize) { Serial.print("Received packet of size "); Serial.println(packetSize); Serial.print("From "); IPAddress remote = Udp.remoteIP(); for (int i=0; i < 4; i++) { Serial.print(remote[i], DEC); if (i < 3) { Serial.print("."); } } Serial.print(", port "); Serial.println(Udp.remotePort());

// read the packet into packetBufffer Udp.read(packetBuffer, UDP_TX_PACKET_MAX_SIZE); Serial.println("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(); } delay(10); }

/* Processing sketch to run with this example

// Processing UDP example to send and receive string data from Arduino // press any key to send the "Hello Arduino" message

import hypermedia.net.*;

UDP udp; // define the UDP object

void setup() { udp = new UDP( this, 6000 ); // create a new datagram connection on port 6000 //udp.log( true ); // <-- printout the connection activity udp.listen( true ); // and wait for incoming message }

void draw() { }

void keyPressed() { String ip = "192.168.1.177"; // the remote IP address int port = 8888; // the destination port

udp.send("Hello World", ip, port ); // the message to send

}

void receive( byte[] data ) { // <-- default handler //void receive( byte[] data, String ip, int port ) { // <-- extended handler

for(int i=0; i < data.length; i++) print(char(data[i])); println(); } */