IGMP Joining of a Multicast

Projects Programming
1

Hi All

Working on project that uses Multicast to receives UDP data, this works fine, however I have been told that I should implement IGMP to send out a message to say what group has been joined.

I have just spent the last hour going round the net trying to find out info, I guess I need to send a message, somewhere I just cant find out what I need to send, where I need to send it?

Can anyone point me in the right direction or example code, this is the code I am using to enable the receive that works fine and the data is receives

IPAddress sACNIP     = {239,255,highByte(sACN_uni), lowByte(sACN_uni)};
udp.beginMulticast(WiFi.localIP(), sACNIP, sACN_PORT);

…

if (udp.parsePacket()) {
  //deal is incoming data

}

Thanks

Brian

2

It turns out all the IGMP is done when you connect to the multicast ! So didn't need to worry about it