Ethernet - EthernetUDP.write()

Description

Writes UDP data to the remote connection. Must be wrapped between beginPacket() and endPacket(). beginPacket() initializes the packet of data, it is not sent until endPacket() is called.

Syntax

EthernetUDP.write(message);
EthernetUDP.write(buffer, size);

Parameters

message: the outgoing message (char)
buffer: an array to send as a series of bytes (byte or char)
size: the length of the buffer

Returns

byte : returns the number of characters sent. This does not have to be read

Example

 

  
#include <SPI.h>        

#include <Ethernet.h>

#include <EthernetUdp.h>



// Enter a MAC address and IP address for your controller below.

// The IP address will be dependent on your local network:

byte mac[] = { 0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0xED };

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);

}



void loop() {

  Udp.beginPacket(Udp.remoteIP(), Udp.remotePort());

    Udp.write("hello");

    Udp.endPacket();

}