Simple UDP communication

scastagnoli · August 2008

Hi there.
I would send UDP packets from my Netlinx controller to a PC (with IP address 192.16.0.10).
My Netlinx source looks something like this in the DEFNE_START section:
IP_CLIENT_OPEN (12345, '192.16.0.10', 54321, 2) (*open the communication*)

instead the DEFINE_EVENT contains:
SEND_STRING 0:12345:0, 'UDP test!'

I cannot receive anything on my PC but I'm sure the listener is ok.
Could someone suggest me how to achieve this simple communication?

Thanks a lot in advance!

Stefano

AMXJeff · August 2008

Why did you pick such a high port number. That means NetLinx has to create a port from 2 all the way upto 12345. That is alot of devices on NetLinx. Pick something smaller, like, lets say...2.

Not Much to UDP.

DEFINE_DEVICE

dvTP = 10001:1:0
dvSocket = 0:2:0;

DEFINE_EVENT

BUTTON_EVENT[dvTP,1]
{
     PUSH:
     {
           // was this the actual IP address of the PC???? Maybe 192.168.0.10????
           IP_CLIENT_OPEN (dvSocket.Port, '192.16.0.10', 54321, IP_UDP) (*open the communication*)

           // Unlike TCP, UDP opens immediately
           SEND_STRING dvSocket, 'UDP test!'

           IP_CLIENT_CLOSE(dvSocket.Port);
     }
}

// Little UDP Test Program, May help to explain UDP Communications

DEFINE_DEVICE

dvMaster = 0:1:0;
dvServer = 0:2:0;
dvServerClient = 0:3:0;
dvClient = 0:4:0;

dvTP		 = 10001:1:0;

DEFINE_CONSTANT

SERVER_PORT = 50000;

DEFINE_VARIABLE

IP_ADDRESS_STRUCT uMyIPStuff;

DEFINE_START

GET_IP_ADDRESS(dvMaster, uMyIPStuff);

WAIT 100 'START UDP SERVER'
{
	IP_SERVER_OPEN(dvServer.Port, SERVER_PORT, IP_UDP);
}

DEFINE_EVENT

BUTTON_EVENT[dvTP,1]
{
	PUSH:
	{
		IP_CLIENT_OPEN(dvClient.PORT, uMyIPStuff.IPADDRESS, SERVER_PORT, IP_UDP_2WAY);
		
		SEND_STRING dvClient,"'Hello, World!'"
	}
}


DATA_EVENT[dvClient]
{
	ONLINE:
	{
		SEND_STRING 0,"'CLIENT OPEN!'";
	}
	STRING:
	{
		SEND_STRING 0,"'SERVER SAID: ',DATA.TEXT";
		
		IP_CLIENT_CLOSE(dvClient.PORT);
	}
}

DATA_EVENT[dvServer]
{
	STRING:
	{
		SEND_STRING 0,"'CLIENT SAID: ',DATA.TEXT";
		
		IP_CLIENT_OPEN(dvServerClient.PORT, DATA.SOURCEIP, DATA.SOURCEPORT, IP_UDP);
		SEND_STRING dvServerClient,'GOT IT!';
		IP_CLIENT_CLOSE(dvServerClient.PORT);
	}	
	OFFLINE:
	{
		SEND_STRING 0,"'SERVER CLOSED!'";
	
		IP_SERVER_OPEN(dvServer.Port, SERVER_PORT, IP_UDP);
	}
	ONLINE:
	{
		SEND_STRING 0,"'SERVER OPEN!'";
	}
}

scastagnoli · August 2008

Thank you very much for the answer AMXJeff!
I've tried the following code:

PROGRAM_NAME='UDPTest'
DEFINE_DEVICE
SERIAL= 5001:1:0
dvSocket = 0:2:0

DEFINE_VARIABLE
LONG TL_ARRAY[] = {1000, 1000}

DEFINE_START
TIMELINE_CREATE (1, TL_ARRAY, 2, TIMELINE_RELATIVE, TIMELINE_REPEAT)

DEFINE_EVENT
DATA_EVENT [SERIAL]
{
ONLINE:
{
SEND_COMMAND DATA.DEVICE, 'SET BAUD 9600,N,8,1'
SEND_STRING SERIAL, 'Online'
}
}
TIMELINE_EVENT[1]
{
SWITCH(TIMELINE.SEQUENCE)
{
CASE 1: SEND_STRING SERIAL, 'Serial Test'
FOR (CONT=1; CONT<=10; CONT++)
{
OFF [Relay, 1]
WAIT 1
ON [Relay, 1]
}

IP_CLIENT_OPEN (dvSocket.Port, '192.16.0.10', 54321, IP_UDP) //IP address is 192.16.0.10 ;-)
SEND_STRING dvSocket, 'UDP test!'
IP_CLIENT_CLOSE(dvSocket.Port)

CASE 2: SEND_STRING SERIAL, 'Serial Test 2'
OFF [Relay, 1]

}
}

DEFINE_PROGRAM

but the listener still doesn't receive anything.
The listener is on port 54321 on the PC and the serial data is shown correctly on my PC using HyperTerminal.
Can you help me a little more?

AMXJeff · August 2008

I would say off hand that the problem is with the UDP Server, or some network issue. I would try the "Little UDP Test Program" that I also gave you and test that you get the responses from Telnet of the master with MSG ON. You should see the following messages.

CLIENT SAID: Hello, World!
SERVER SAID: GOT IT!

scastagnoli · August 2008

Thank you very much AMXJeff!!!
After some attempts I've made it works! Now I can receive packets from a PC and send to another using UDP protocol!

Thanks thanks thanks!

Simple UDP communication

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