| FB-Name | UA_Connect |
| This Function Block is used to create a (optional secure) transport connection and an OPC UA session. The connection shall be terminated by calling the UA_Disconnect after establishing the connection. |
| VAR_INPUT |
| B | Execute | BOOL | On rising edge connection is started. |
| B | ServerEndpointUrl | Vendor specific | Shall be STRING or WSTRING. The recommendation for new implementation is to use WSTRING. URL |
| B | SessionConnectInfo | STRUCT | See UASessionConnectInfo |
| B | Timeout | TIME | Maximum time to establish the connection. |
| VAR_OUTPUT |
| B | Done | BOOL | Signals a connection has been initially established. |
| B | Busy | BOOL | The FB is not finished and new output values are to be expected. |
| B | Error | BOOL | Signals that an error has occurred within the FB. |
| B | ErrorID | DWORD | Error code. |
| B | ConnectionHdl | DWORD | Connection handle – is valid until UA_Disconnect is called. |
| Notes: The connection monitoring and the reconnect handling are to be done by the client vendor implementation. The reconnect sequence is defined in OPC 10000-4. |
