• Create a "Standard project" and select CODESYS Control Win V3 as the device.
• Define the target system by means of the Network scan.
  
  
  
  
  

As of SP17:

• Open the Library Manager and add the following libraries:
  Net Base Services
  StringUtils
  
  
  
  
  

• Create a global variable list named gvlSettings gvlSettings and define the following variables:
  
  

  ---

  
  

  {attribute 'qualified_only'}
  VAR_GLOBAL
      // !!!  Make sure that the firewall does not block these ports !!!
  	uiPort		: UINT	:= 50000; // Port for the sender => receiver will set to uiPort + 1
  	sIPAddres  	: STRING(19) 		:= '192.168.99.109';
  END_VAR

  
  

  ---

  
  
  
  

• Add a POU to the project and name is UdpClient.
  
  
  
  
  
• Adapt the POU UdpClient as follows:
  
  

  ---

  
  

  Declaration

  VAR
  	fbPeerClient	: NBS.UDP_Peer;
  	ipAddress		: NBS.IPv4Address;
  	xPeerActiv		: BOOL  := TRUE;
  	
  	fbSend			: NBS.UDP_Send;
  	xSend			: BOOL;
  	
  	sSendMsg		: STRING(255) := 'Hello World';
  END_VAR

  
  

  ---

  
  

  Implementation

  IF xPeerActiv AND NOT fbPeerClient.xBusy THEN
  	ipAddress.SetInitialValue(ipAddress := gvlSettings.sIPAddres);
  	fbPeerClient(xEnable := TRUE, 
  				itfIPAddress := ipAddress, 
  				uiPort := gvlSettings.uiPort + 1);	
  END_IF
  
  fbPeerClient();
  
  
  fbSend(xExecute := xSend AND fbPeerClient.xBusy, 
  					itfPeer := fbPeerClient, 
  					itfIPAddress := ipAddress, 
  					uiPort := gvlSettings.uiPort,  
  					pData := ADR(sSendMsg), 
  					udiSize := DINT_TO_UDINT(Stu.StrLenA(ADR(sSendMsg))));	
  
  IF xSend THEN
  	xSend := FALSE;
  END_IF

  
  

  ---

  
  
  
  
• Adapt the POU PLC_PRG as follows:
  
  

  ---

  
  

  Declaration

  VAR
  	fbPeerServer		: NBS.UDP_Peer;
  	ipAddress			: NBS.IPv4Address;
  	fbReceive			: NBS.UDP_Receive;
  	xPeerActiv			: BOOL  := TRUE;
  	
  	xRead				: BOOL;
  	abyReceive			: ARRAY [0..255] OF BYTE;
  	
  	sLastValidReceive	: STRING(255);
  	udiIndex			: UDINT;
  END_VAR

  
  

  ---

  
  

  Implementation

  IF xPeerActiv AND NOT fbPeerServer.xBusy THEN
  	ipAddress.SetInitialValue(ipAddress := gvlSettings.sIPAddres);
  	fbPeerServer(xEnable := TRUE, 
  					itfIPAddress := ipAddress, 
  					uiPort := gvlSettings.uiPort);	
  END_IF
  
  fbPeerServer();
  
  fbReceive(xEnable := fbPeerServer.xBusy, itfPeer := fbPeerServer, pData := ADR(abyReceive), udiSize := SIZEOF(abyReceive));
  
  IF fbReceive.udiCount > 0 THEN
  	IF fbReceive.udiCount < SIZEOF(sLastValidReceive) THEN
  		SysMem.SysMemCpy(pDest := ADR(sLastValidReceive), pSrc := ADR(abyReceive), udiCount := fbReceive.udiCount);
  		// Set End of String
  		sLastValidReceive[fbReceive.udiCount] := 0;
  	END_IF
  END_IF
  
  UdpClient();

  
  

  ---

  
  
  
  

• Start the project and set the xSend variable to TRUE.
  
  
  
  
  
  
  

Up to SP16:

• Open the Library Manager and add the Network library.
  
  
  

• Add a global variable list to the project and define the following variables:
  
  

  ---

  {attribute 'qualified_only'}
  VAR_GLOBAL
      sIpAddr    :    NBS.IP_ADDR := (sAddr := '192.168.99.74'); // Change to own IP-Address
  	// !!!  Make sure that the firewall does not block these ports !!! 
      uiPort     :    UINT := 8181; // Port for the sender => receiver will set to uiPort + 1
  END_VAR

  ---

• Add a POU to the project and name is UdpClient.
  
  
  
  

• Adapt the POU UdpClient as follows:
  
  

  ---

  Declaration

  VAR
      fbPeerClient    :    NBS.UDP_Peer;
      fbReceive       :    NBS.UDP_Receive;
      sRcvMsg         :    STRING;
  END_VAR

  ---

  Implementation

  fbPeerClient(xEnable := TRUE, ipAddr:= GVL.stIpAddr, uiPort:= GVL.uiPort + 1);
  
  fbReceive(xEnable := (fbPeerClient.hPeer <> CAA.gc_hINVALID), 
              hPeer := fbPeerClient.hPeer, 
              szSize := SIZEOF(sRcvMsg), 
              pData := ADR(sRcvMsg));

  ---

• Adapt the POU PLC_PRG as follows:
  
  

  
  

  ---

  
  

  Declaration

  VAR
  	fbPeerServer    :    NBS.UDP_Peer;
      fbSend          :    NBS.UDP_Send;
      xSend           :    BOOL;
      sSendMsg        :    STRING := 'Hello World';
  END_VAR

  ---

  Implementation

  UdpClient();
  
  fbPeerServer(xEnable := TRUE, ipAddr := GVL.stIpAddr, uiPort := GVL.uiPort);
  
  IF fbPeerServer.hPeer <> CAA.gc_hINVALID THEN
      fbSend(xExecute := xSend, 
              hPeer := fbPeerServer.hPeer,
              ipAddr := GVL.stIpAddr, 
              uiPort := GVL.uiPort + 1, 
              szSize := SIZEOF(sSendMsg), 
              pData := ADR(sSendMsg));
  END_IF
  
  IF xSend THEN
      xSend := FALSE;
  END_IF

  ---

• Start the project and set the xSend variable to TRUE.