To
add a server either right-click the Node or press the 'Add Server' button on
the toolbar to invoke the server selection form.
The
form scans for network nodes when it comes up. Double-click on a node
to check it for OPC servers. If no servers exist the timeout could be
20-30 seconds. These search actions run on a separate thread and will not block currently updating data. The status message and
progress bar at the bottom gives feedback on the search progress.
Double-click on the domain to refresh the list of network nodes.
You can manually enter the server name of nodes that don't
publish themselves on the LAN to add them to the tree.
Once you select a
server it will be added to the TagServer's tree control and then connected. The
network node will also be added if it doesn't already exist. To explicitly
connect or disconnect servers use the toolbar buttons or right-click and use
the popup menu.
The disconnected
state is indicated by the slashed circle over the tree item.
Select the server
properties dialog to configure the server object.
Name
- Give the server a descriptive name.
Description
- Add additional information to be saved with the server.
Parent
- Parent object in the tree.
Guid,
ProgID - The globally unique identifier and the program
identifier are read when the server is located and can be inspected here.
In theory, you could manually disconnect, change the ProgID or Guid and
reconnect to access a different server on the same node. The Guid is
used unless it doesn't exist and then the ProgID is used for getting COM
objects and interfaces.
Vendor - Server vendor information.
Version - Server version.
Mode -
Operational mode of the server.
Connected
- Is the server object connected to the server
application?
WatchdogPeriod - This is the period, in milliseconds, to check
communications by calling the OPC
server's GetStatus method. If GetStatus fails, or times out, the
server is disconnected and a PropertyChanged event is sent to subscribers
that includes ServerMode.StatusCheckFail. The main form displays the
associated error messages in the output window and detects that the
'Connected' property has change to disconnected and applies the red slashed
circle to the server's tree item.
WriteTimeoutPeriod - Writes are done asynchronously. This is
the period of time to allow for a write conformation to be sent from the
server before generating a write timeout error message. Write timeout
messages are sent to subscribers of the TagServer's Errored event.
