Hey,
I am trying to set up my Arduino Mega with an Arduino Ethernet Shield 2 (W5500) so that I can send UDP messages from another program through an ethernet cable to control the pins of the Mega.
I'm having trouble getting even the first steps and trials to work. I have found a couple of other threads related to my problem and have tried some of the suggested solutions but nothing works, I just keep getting the LinkOFF message but my cable is for sure connected and the shield leds are on. I have manually set the IP and the mac address is the one from the sticker. This is the code I'm running:
#include <SPI.h>
#include <Ethernet.h>
#include <EthernetUdp.h>
#define SDSelect 4
// Enter a MAC address and IP address for your controller below.
// The IP address will be dependent on your local network:
byte mac[] = {
0xA8, 0x61, 0x0A, 0xAF, 0x03, 0xBC
};
IPAddress ip(192, 168, 0, 3);
IPAddress gateway(192, 168, 0, 4);
IPAddress subnet(255, 255, 255, 0);
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
pinMode (SDSelect, OUTPUT);
digitalWrite (SDSelect, HIGH);
// start the Ethernet
Ethernet.begin(mac, ip);
// Open serial communications and wait for port to open:
Serial.begin(115200);
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.");
}
if (Ethernet.linkStatus() == LinkON) {
Serial.println("Ethernet cable is found, all good.");
}
if (Ethernet.linkStatus() == Unknown) {
Serial.println("Link status unknown.");
}
// 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 packetBuffer
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);
}
