Arduino: Ethernet UDP Receive Data

Sumber: https://www.arduino.cc/en/Reference/EthernetUDPRead

Ethernet : UDP.read()

Baca UDP data dari buffer yang di tentukan. Jika tidak ada argumen yang diberikan, dia akan memberikan karakter selanjutnya yang ada di buffer.

Fungsi ini hanya dapat di panggil secara baik sesudah UDP.parsePacket().

Syntax

UDP.read();
UDP.read(packetBuffer, MaxSize);

Parameter

packetBuffer: buffer to hold incoming packets (char)
MaxSize: maximum size of the buffer (int)

Returns

char : returns the characters in the buffer

Code

#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, 0, 3);

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

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

char packetBuffer[UDP_TX_PACKET_MAX_SIZE]; //buffer to hold incoming packet,

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

void loop() {

  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);
  }
}

Referensi

• https://www.arduino.cc/en/Reference/EthernetUDPRead