t41_to_t41_comm/eth_tcp_receiv.ino

#include <NativeEthernet.h>
#include <NativeEthernetServer.h>

byte mac[] = { 0x04, 0xE9, 0xE5, 0x10, 0x00, 0x02 };
IPAddress ip(192, 168, 1, 101);
const int localPort = 8888;

EthernetServer server(localPort);
EthernetClient client;
#define package_size 1024
byte packetBuffer[package_size];

void setup() {
    Serial.begin(921600);
    //while (!Serial);

    Serial.println("Initializing Ethernet...");
    Ethernet.begin(mac, ip);

    if (Ethernet.hardwareStatus() == EthernetNoHardware) {
        Serial.println("Ethernet hardware not found!");
        while (true);
    }

    if (Ethernet.linkStatus() == LinkOFF) {
        Serial.println("Ethernet cable not connected!");
    }

    server.begin();
    Serial.println("TCP Server Ready. Waiting for connections...");
}

void loop() {
    if (!client || !client.connected()) {
        client = server.available();
        if (client) {
            Serial.println("Client connected!");
        }
        return;
    }

    static int bytesReceived = 0;

    while (client.available()) {  // Keep reading while data is available
        int byteRead = client.read(packetBuffer + bytesReceived, package_size - bytesReceived);
        if (byteRead > 0) {
            bytesReceived += byteRead;
        }

        if (bytesReceived == package_size) {  // Full packet received
            //Serial.print("Received packet at: ");
            Serial.println(micros());
            //Serial.println(" us");

            //for (int i = 0; i < package_size; i++) {
                //Serial.print(packetBuffer[i], DEC);
                //Serial.print(" ");
                //if ((i + 1) % 256 == 0) Serial.println();
            //}
            //Serial.println();

            bytesReceived = 0;  // Reset for the next packet
        }
    }
}