Connecting Controls and Indicators to Shared Variables

You can connect front panel objects to shared variables to read and write shared variable data.

Creating a Shared Variable Control and Shared Variable Constant

Use the shared variable control and shared variable constant to select, browse to, or enter shared variables for use in VIs. You can wire the shared variable control and shared variable constant into Alarms & Events VIs, Historical VIs, DataSocket VI and functions, and the Shared Variables VIs. You also can configure alarms, scaling, security, and logging options using the SharedVariableIO properties. To access the SharedVariableIO properties, right-click a shared variable constant on the block diagram and select Create»Property from the shortcut menu.

By default, the shared variable control and shared variable constant accept any name. You can configure the shared variable control or shared variable constant to accept only names of existing shared variables by right-clicking the shared variable object and removing the checkmark from Allow Undefined Names in the shortcut menu. Removing the checkmark from Allow Undefined Names means that you must enter the name of an existing shared variable into the shared variable object.

When you save VIs that contain a shared variable control or shared variable constant, each shared variable control and shared variable constant retains the shared variable name that you selected.

Adding and Customizing Graphics

The DSC Module Controls palette includes Boolean controls and indicators such as pipes, valves, and pumps, and numeric controls and indicators such as tanks and hoppers. These images change to reflect the state of the shared variables to which you connect them.

The LabVIEW Datalogging and Supervisory Control (DSC) Module also includes the Image Navigator, which is an extensive library of supervisory control images and other images ranging from basic geometric shapes to drawings of special equipment. You can launch the Image Navigator by selecting Tools»DSC Module»Image Navigator. Refer to the Image Navigator Help, available by selecting Help»Contents in the Image Navigator, for more information about editing, copying, and importing and exporting graphics with the Image Navigator.

Security Configuration

The DSC Module includes the Front Panel Security dialog box, available by selecting Tools»Security»Front Panel Security, to allow you to add security options to many front panel objects. You also can add security to front panel objects individually with the Security tab of the object properties dialog box, available by right-clicking the control or indicator and selecting Properties from the shortcut menu.