Arduino Function: EthernetUDP.parsePacket

Description

Checks for the presence of a UDP packet, and returns the size. This function must be called before reading the buffer with UDP.read().

Syntax

UDP.parsePacket();

Returns

 It returns the size of a received UDP packet Int

Examples

#include <SPI.h> // needed for Arduino versions later than 0018
#include <Ethernet.h> //If you are using Ethernet Shield 2, use instead <Ethernet2.h>
#include <EthernetUdp.h> // UDP library from: bjoern@cs.stanford.edu 12/30/2008


// Enter a MAC address and IP address for your controller below.
byte mac[] = { 0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0xED };
// The IP address will be dependent on your local network:
IPAddress ip(192, 168, 1, 177);

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

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

void setup() {
// start the Ethernet and UDP:
Ethernet.begin(mac,ip);
Udp.begin(localPort);
Serial.begin(9600);
}

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);
}
delay(10);
}


Based on the reference originally written by Arduino Community,  wiring.org.co and  arduino.cc