ServerTCP (FB)

FUNCTION_BLOCK ServerTCP EXTENDS Server

MODBUS TCP server (slave).

ServerTCP processes MODBUS TCP requests by up to 16 parallel client connections.

For details about supported function codes and “data model” see Server.

Please note: some input variables related to connection configuration are read when rising edge on xEnable occurs. To change connection configuration the application needs to - disconnect (xEnable := FALSE and execute the FB) - modify the related input variables - connect (xEnable := TRUE and execute the FB)

The Server provides some statistics of received valid requests messages and sent reply messages. Invalid messages are dropped at the communication level, so doesnt appear in the statistics. To analyse situations where invalid reply messages might occur, you can use udiLogOptions with LoggingOptions.WarnOnReceivedInvalidFrames.

Please visit https://forge.codesys.com/prj/codesys-example/modbus/home to find examples.

InOut:

Scope	Name	Type	Initial	Comment	Inherited from
Input	xEnable	BOOL	FALSE	Enables the server, take over the configuration information fcsSupported and dataModel. If the “data model” (tableDefinitions) contains configuration errors, the Server will not got busy (xBusy = FALSE).	Server
	fcsSupported	SupportedFcs	Constants.SUPPORTED_FCS_SIMPLE_SERVER	Supported “function codes”, accepted at xEnable FALSE => TRUE. In case fcsSupported is not assigned by the application it defaults to Constants.SUPPORTED_FCS_SIMPLE_SERVER.	Server
	dataModel	TableDefinitions		“data model”, accepted at xEnable FALSE => TRUE.	Server
	tInactivityInfoTime	UDINT	0	“inactivity info time” (in milliseconds). If no valid requests are received in this time xInactive is signaling inactivity - default = 0 -> no “inactivity info”.	Server
Output	xRunning	BOOL		Server is up and running, waiting for requests.	Server
	xError	BOOL		Error	Server
	eErrorID	Error		Error status	Server
	xInactive	BOOL		No valid requests received for tInactivityTimeOut.	Server
	udiNumMsgRecv	UDINT		Number of request messages received since enabling the Server.	Server
	udiNumMsgReply	UDINT		Number of reply messages send since enabling the Server.	Server
	udiNumMsgExcReply	UDINT		Number of exception reply messages send since enabling the Server.	Server
	udiNumMsgExcReplyIllFct	UDINT		Number of exception reply messages send since enabling the Server, signaling illegal function.	Server
	udiNumMsgExcReplyIllDataAdr	UDINT		Number of exception reply messages send since enabling the Server, signaling illegal data address.	Server
	udiNumMsgExcReplyIllDataValue	UDINT		Number of exception reply messages send since enabling the Server, signaling illegal data value.	Server
	xReadRequest	BOOL		Read request(s) happened since last call, rejected requests included.	Server
	udiNumReadRequests	UDINT		Read request counter, rejected requests included.	Server
	xWriteRequest	BOOL		Write request(s) happened since last call, rejected requests included.	Server
	udiNumWriteRequests	UDINT		Write request counter, rejected requests included.	Server
Input	wsInterfaceName	WSTRING(255)		ETH interface name to bind to, “” to bind to any ETH interface. Only read when rising edge on xEnable occurs.
	uiPort	UINT	502	ETH port to use. Only read when rising edge on xEnable occurs.
	xReset	BOOL	FALSE	Reset the server.
	udiLogOptions	UDINT	LoggingOptions.ServerStartStop	Logging options.
Output	uiConnectedClients	UINT		Number of actually connected clients.

• Log
  • ServerTCP.LogStatusInfo (METH)