Using front panel data binding to control a front panel control remotely through the Shared Variable Engine provides faster and more reliable data transmission than dstp as well as seamless connections to shared variables and NI Publish-Subscribe Protocol (NI-PSP) data items.
Complete the following steps to read front panel data using the opc, ftp, or http protocols on Windows, and the dstp and file protocols on all LabVIEW-supported platforms.
|Note You must install the DataSocket Server to read dstp front panel data.|
- If you are using a dstp connection, launch and configure the DataSocket Server. If you are using an opc, ftp, http, or file connection, skip to step 2. Open the DataSocket Server by selecting Start»All Programs»National Instruments»DataSocket»DataSocket Server.
- Right-click a front panel object and select Properties from the shortcut menu to display the Properties dialog box for the object.
- Click the Data Binding tab of the Properties dialog box.
- Select DataSocket from the Data Binding Selection pull-down menu.
- On Windows, enter an opc, ftp, or http URL, or on all LabVIEW-supported platforms enter a file or dstp URL in the Path text box. You also can select DSTP Server or File System on all LabVIEW-supported platforms from the Browse pull-down menu to navigate to a URL.
- Select Read only from the Access Type pull-down menu.
- Click the OK button.
- On the block diagram, create a While Loop to configure the VI to run continuously.
- Run the VI. LabVIEW retrieves the data from the DataSocket Server and displays it in the front panel object of the VI. While the VI is running, if the connection to the DataSocket Server is successful, a small green indicator appears next to the front panel object on the VI. If the connection is not successful, a small red indicator appears. Before LabVIEW attempts to connect to the server, a small transparent indicator appears. A status message also appears if you move the cursor over the indicator. You can hide this indicator by right-clicking the front panel object and selecting Visible Items»DataSocket LED from the shortcut menu when the VI is not running. You also can use the LED Visible property to hide the indicator programmatically.