Configure an OPC data source object

Add an OPC data source object to your Gateway Communication Driver hierarchy

1. Right-click Configuration in the hierarchy, and select Add OPC Connection from the shortcut menu. The following rules apply:

   A new object is created in the hierarchy tree and is named New_OPC_000 by default (in "edit mode"). Rename it, if desired.

   The New_OPC_001 Parameters configuration view (right pane) is displayed.

2. Configure the new OPC object according to the following option definitions:

   • Server Node: The computer node on which the specified data source can be found. Default value is localhost. Use the browse button to select from a list of all nodes on your network.

   • Server Name: ProgID or ClassID of the OPC server (example of a ProgID: OI.Gateway.3, ClassIDs are GUIDs). Use the browse button to select from a list of OPC server ProgIDs on your network. Default value is blank.

     Note: Use ClassID when referencing a server that does not use OPC enum to enumerate a ProgID.

   • Reconnect Attempts: Number of times Gateway Communication Driver attempts to reconnect to the specified data source if a connection fails. The value (-1) means no limit to the number of attempts. The value Zero (0) means no attempts. Minimum/maximum range is -1 to 1,000,000. Default value is 3.

   • Reconnect Period: Delay (in ms) between reconnect attempts if a connection fails. Minimum/maximum range is 10,000 to 300,000 ms (corresponding to the range of 10 sec to 5 min). Default value is 30000 ms.

   • Poke Retries: Number of times Gateway Communication Driver attempts to retry the write operation if a write operation fails. The value zero (0) means no retry attempts. Minimum/maximum range is 0 to 100. Default value is zero (0).

3. Configure OPC options.

   • Activate Server Out of Proc: When selected, Gateway Communication Driver will attempt to start the external OPC Server Out-of-Proc. When not selected, it will attempt to start the external OPC Server In-Proc. For more information, see In-Proc/Out-of-Proc.

   • Allow Optional Data Type Suffix in Item Name: When selected and a VT suffix is appended to the item name, Gateway Communication Driver adds the item to the OPC server with the requested type set to the type specified in the VT suffix. Gateway Communication Driver removes the VT suffix from the item name string before the item is added to the OPC server.

     If selected and no VT suffix is appended to the item name, Gateway Communication Driver adds the item to the OPC server with requested type = VT_EMPTY.

     If not selected, the item name is passed to the OPC server with requested type = VT_EMPTY. Gateway Communication Driver does not parse the item names looking for a VT suffix.

     For more information, see Use VT item suffixes.

   • Use Synchronous Reads and Writes: When selected, items advising reads and writes will be using synchronous API for communication.