Function Block: ModbusTCPSlave

Library: IoDrvModbusTCP

This block is generated for each Modbus Server TCP in the device tree. This function block represents a TCP/IP connection to an individual Modbus TCP Server. The channels defined for this device are processed in the background. The inputs and outputs of this block provide status information to the user and allow the ability to confirm occurring errors (in order to continue processing). The Enable property is used to start and stop communication.

Note

The Enable property is available only when the Enable diagnosis for devices option is selected on the PLC Settings tab.

Table 17. Inputs (VAR_INPUT)

Name	Data Type	Initial Value	Description
`xConfirmError`	`Bool`	`FALSE`	The process is continued with a rising edge.

Table 18. Outputs (VAR_OUTPUT)

Name	Data Type	Initial Value	Description
`xInitDone`	`Bool`	`FALSE`	Displays the number of communication servers
`xBusy`	`Bool`	`FALSE`	`TRUE` while a request is in process
`xDone`	`Bool`	`FALSE`	`TRUE` if a request was ended successfully
`xError`	`Bool`	`FALSE`	`TRUE` if a request was ended with errors
`byModbusError`	`MB_ErrorCodes`		Specifies the current errors as defined in the enumeration `MB_ErrorCodes`
`ComSettings`	`ModbusTCPCommSettings`		Currently configured communication settings
`xConfirmError`	`Bool`	`False`	The process is continued with a rising edge.

Method: UpdateCommunicationSettings

The communication parameters can be updated only if the server is set to "Stop". The Enable property is used to stop and start the server.

Table 19. Inputs (VAR_INPUT)

Name	Data Type	Initial Value	Description
`ipAdress`	`ARRAY [0..3] OF BYTE`		IP address of the server
`uiPort`	UNIT		Port of the server

Table 20. Outputs (VAR_OUTPUT)

Name	Data Type	Initial Value	Description
`UpdateCommunicationSettings`	`UDINT`		Leads to an error (return value != 0) if a TCP connection exists