UA_Connect

This function block establishes an OPC UA Remote connection to another OPC UA Server, which is specified via ServerUrl and SessionConnectInfo. The function block returns a connection handle that can be used for other function blocks, such as UA_Read.

Inputs

VAR_INPUT
    Execute            : BOOL;
    ServerUrl          : STRING(MAX_STRING_LENGTH);
    SessionConnectInfo : ST_UASessionConnectInfo;     
    Timeout            : TIME := DEFAULT_ADS_TIMEOUT; 
END_VAR

Name	Type	Description
Execute	BOOL	The command is triggered by a rising edge at this input.
ServerUrl	STRING(MAX_STRING_LENGTH)	OPC UA Server URL, i.e. 'opc.tcp://172.16.3.207:4840' or 'opc.tcp://CX_0193BF:4840'.
SessionConnectInfo	ST_UASessionConnectInfo	Connection information (see ST_UASessionConnectInfo)
Timeout	TIME	Time until the function is aborted. DEFAULT_ADS_TIMEOUT is a global constant, set to 5 seconds. The value must be set to match the ST_UASessionConnectInfo.tConnectionTimeout. The rule of thumb is: ADS Timeout > 2 * ConnectionTimeout.

Outputs

VAR_OUTPUT
    ConnectionHdl : DWORD;
    Done          : BOOL;
    Busy          : BOOL;
    Error         : BOOL;
    ErrorID       : DWORD;
END_VAR

Name	Type	Description
ConnectionHdl	DWORD	OPC UA connection handle.
Done	BOOL	Switches to TRUE if the function block was executed successfully.
Busy	BOOL	TRUE until the function block has executed a command, at the most for the duration of the "Timeout" at the input. The inputs accept no new command as long as Busy = TRUE. It is not the connection time that is monitored but the reception time.
Error	BOOL	Switches to TRUE if an error occurs while executing a command. The command-specific error code is included in ErrorID.
ErrorID	DWORD	Contains the command-specific error code of the most recently executed command.

Requirements

Development environment	Target platform	PLC libraries to include
TwinCAT 3.1	Win32, Win64, CE-X86, CE-Arm®	Tc3_PLCopen_OpcUa