ClientSerial (FB)¶

FUNCTION_BLOCK ClientSerial EXTENDS Client IMPLEMENTS ISysComUser

MODBUS serial client (master).

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

The Client provides some statistics of sent request messages and received valid 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	xConnect	BOOL	FALSE	Connect to server (slave).	Client
Output	xConnected	BOOL		Client (master) is connected to server (slave).	Client
	xError	BOOL		Error	Client
	eErrorID	Error		Error status	Client
	udiNumMsgSent	UDINT		Number of request messages send since connect.	Client
	udiNumMsgReply	UDINT		Number of reply messages received since connect.	Client
	udiNumMsgExcReply	UDINT		Number of exception reply messages received since connect.	Client
	udiNumMsgExcReplyIllFct	UDINT		Number of exception reply messages received since connect, signaling illegal function.	Client
	udiNumMsgExcReplyIllDataAdr	UDINT		Number of exception reply messages received since connect, signaling illegal data address.	Client
	udiNumReplyTimeouts	UDINT		Number of reply timeouts since connect.	Client
	udiNumReqNotProcessed	UDINT		Number of requests not processed in time (“request starvation”) since connect.	Client
	udiNumReqParamError	UDINT		Number of requests started with parameter error, for example “Read Coils” -> “Quantity of coils” = 0.	Client
	udiLastTransactionTime	UDINT		Transaction time in ms - time difference between request message send und reply message received.	Client
Input	iPort	SysCom.SYS_COM_PORTS	SysCom.SYS_COM_PORTS.SYS_COMPORT_NONE	Serial port, only read when rising edge on xConnect occurs.
	dwBaudrate	SysCom.SYS_COM_BAUDRATE	SysCom.SYS_COM_BAUDRATE.SYS_BR_115200	Baud rate, only read when rising edge on xConnect occurs.
	byDataBits	BYTE	8	Number of data bits/BYTE, 4-8, only read when rising edge on xConnect occurs.
	eParity	SysCom.SYS_COM_PARITY	SysCom.SYS_COM_PARITY.SYS_NOPARITY	Parity, only read when rising edge on xConnect occurs.
	eStopBits	SysCom.SYS_COM_STOPBITS	SysCom.SYS_COM_STOPBITS.SYS_ONESTOPBIT	Stop bits, only read when rising edge on xConnect occurs.
	eDTRcontrol	SYS_COM_DTR_CONTROL	SysCom.SYS_COM_DTR_CONTROL.SYS_DTR_CONTROL_DISABLE	DTR control, only read when rising edge on xConnect occurs.
	eRTScontrol	SysCom.SYS_COM_RTS_CONTROL	SysCom.SYS_COM_RTS_CONTROL.SYS_RTS_CONTROL_DISABLE	RTS control, only read when rising edge on xConnect occurs.
	eRtuAscii	RtuAscii	RtuAscii.RTU	RTU / ASCII, only read when rising edge on xConnect occurs.
	udiLogOptions	UDINT	LoggingOptions.ClientConnectDisconnect	Logging options.