UDP SendAll fails after number of chars reaches 1473

bugs, errors
#1

I am sending char * from OF to a teensy board.

Here is my OF code:

void ofApp::draw() {
    string message = "";
    int total = 1472;
    for (int i = 0; i < total; i++) {
        message += (char)ofRandom(0,255);
    }
    udpConnection.SendAll(message.c_str(), message.length());
}

Here is my teensy code:

void loop() {
  int packetSize = Udp.parsePacket();
  if (packetSize) {
    Serial.println("Got it!");
    Udp.read((char*)packetBuffer, 648*3);
    for (int i = 0; i <  3*NUM_LEDS; i+=3) {
      leds[i/3].setRGB(packetBuffer[i], packetBuffer[i+1], packetBuffer[i+2]);
    }
    FastLED.show();
  }
}

The teensy code responds when it receives a packet of any size, which works fine up to 1472 chars. In the OF code, as soon as the length of the char * length is increased to 1473, the teensy stops receiving anything, and I am not getting any run time errors OF-side. Does anyone know why this would happen/what the fix is? I need to scale this up to 1944 chars eventually

Thanks,

Collin

#2

udp can fail without notice, what’s surely going on is that the message is getting bigger than the max package size of the network, the network just discards the message and you want get any notification. if you need the message to always arrive no matter the size the easiest is to use tcp instead of udp