基于arduino的esp32 udp组播接收程序

以下是基于Arduino的ESP32 UDP组播接收程序示例：

#include <WiFi.h>
#include <WiFiUdp.h>

const char* ssid = "YOUR_WIFI_SSID";
const char* password = "YOUR_WIFI_PASSWORD";
const uint16_t multicastPort = 1900;
const IPAddress multicastIP(239, 255, 255, 250);

WiFiUDP udp;

void setup() {
  Serial.begin(115200);

  WiFi.mode(WIFI_STA);
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(1000);
    Serial.println("Connecting to WiFi...");
  }
  Serial.println("Connected to WiFi");

  if (!udp.beginMulticast(WiFi.localIP(), multicastIP, multicastPort)) {
    Serial.println("Failed to begin multicast");
    while (1) {
      delay(1000);
    }
  }
  Serial.println("Multicast receiver started");
}

void loop() {
  static char rx_buffer[128];
  int packetSize = udp.parsePacket();
  if (packetSize) {
    IPAddress remoteIP = udp.remoteIP();
    uint16_t remotePort = udp.remotePort();
    int len = udp.read(rx_buffer, sizeof(rx_buffer) - 1);
    if (len > 0) {
      rx_buffer[len] = 0;
      Serial.printf("Received %d bytes from %s:%d\n", len, remoteIP.toString().c_str(), remotePort);
      Serial.println(rx_buffer);
    } else {
      Serial.println("Failed to receive data");
    }
  }
}

在这个示例中，我们首先连接WiFi。然后，我们创建一个UDP套接字并将其绑定到本地IP地址和端口。接下来，我们加入多播组并等待接收数据。当数据到达时，我们打印接收到的数据和来源地址和端口。