Use the Custom VI-based Server – Periodic Wizard to create a periodic I/O server. The Custom VI-based Server – Periodic Wizard converts a VI into a custom I/O server that runs as a service and publishes NI Publish-Subscribe Protocol (NI-PSP) data items to the network. LabVIEW automatically launches, registers, initializes, performs error handling, and shuts down the periodic I/O server when necessary.
The Shared Variable Engine (SVE) launches the periodic I/O server when you load a LabVIEW process that includes a periodic I/O server. The periodic I/O server executes until the specified stop condition occurs. If the stop condition occurs and the periodic I/O server does not shut down by the specified timeout value, the VI aborts and generates an event of priority 500.
Before you create a periodic I/O server in LabVIEW, first create a data access VI that retrieves or emulates hardware data values in a loop structure. You then can use the Custom VI-based Server – Periodic Wizard to convert the VI to a periodic I/O server and configure the periodic I/O server in a process.
Use the following guidelines when you create the data access VI:
The Custom VI-based Server – Periodic Wizard checks these items when you attempt to convert a data access VI to a periodic I/O server.
To convert the data access VI into a periodic I/O server, right-click My Computer or a LabVIEW project library in the Project Explorer window and select New»I/O Server from the shortcut menu. In the Create New I/O Server dialog box, select Custom VI - Periodic and click the Continue button to create and configure the periodic I/O server. The Custom VI-based Server – Periodic Wizard creates the following files:
Use the NI Distributed System Manager to ensure that the periodic I/O server publishes values as expected.
|Note After the testing, you can build an application for this periodic I/O server and redistribute this application to a target computer.|