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custom UDP messages [message #1818556]

Thu, 19 December 2019 14:35

Niklas Huhs

Messages: 28
Registered: October 2019

Junior Member

Hello everybody,

I am trying to create a block, which sends out a custom UDP message.
I already have a block using the "sendDataOnUDP" function and in debug messages in the console I can see that it is sending out the right amount of bits.
But still the message seems to get stuck somewhere as I cannot see anything while watching the network via wireshark.
The code for execute function looks like this:

void FORTE_WriteProp::executeEvent(int pa_nEIID){
	paket_t WP;
	
	char* acIPAddr = "xxx.xxx.xxx.xxx"; /
	
	unsigned short Port;
	Port = xxxxx;
	CBSDSocketInterface::TUDPDestAddr DestAddr;
	const char* IP = "xxx.xxx.xxx.xxx";
	DestAddr.sin_family = AF_INET;
	DestAddr.sin_port = htons(Port);
	DestAddr.sin_addr.s_addr = inet_addr(IP);

	CBSDSocketInterface::TSocketDescriptor Socket;
	char* packet;
	packet = (char*)&WP;
	switch(pa_nEIID){
    case scm_nEventINITID:
		
		
		
		
	
      break;
    case scm_nEventREQID:
		int test;
	
	
		Socket = CIPComSocketHandler::openUDPSendPort(acIPAddr, Port, &DestAddr);
		test =CIPComSocketHandler::sendDataOnUDP(Socket, &DestAddr, packet, sizeof(WP));
		
      break;
  }
}

Compiling works without problems and I get return values from the functions. But probably there is something in the forte code which I didnt consider.

Does anybody have an idea?

best regards

[Updated on: Thu, 19 December 2019 16:24]

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Re: custom UDP messages [message #1818569 is a reply to message #1818556]

Thu, 19 December 2019 20:01

Alois Zoitl

Messages: 1209
Registered: January 2014

Senior Member

At a first look I don't see any obvious. However you should definitely not open in the REQ a socket. This is a time consuming process. Furthermore have you considered our communication layer approach [1]? With that you just need to programm the message payload generation in your own layer and can reuse much more 4diac FORTE code. Even our FBs. I guess in your case the publish and subscribe.

But coming back to your problem: Not seeing messages in wireshark can have several reasons: routing tables, not running loop back devices, firewall, networkswitch. Therefore it could be something totally outside of 4diac FORTE.

[1] https://www.eclipse.org/4diac/en_help.php?helppage=html/development/forte_communicationArchitecture.html

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Re: custom UDP messages [message #1818589 is a reply to message #1818569]

Fri, 20 December 2019 08:41

Niklas Huhs

Messages: 28
Registered: October 2019

Junior Member

Thanks for your answer.
I considered it but thought it might be easier and faster to program two blocks to do the job. But I guess in the end it might be less work to use the communication layer approach so I think I will use that one again.

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