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BACnet Program Display Object


Display microblock

The BACnet Program Display Object microblock defines a standardized object whose properties represent the externally visible characteristics of an application program and makes these characteristics available to the WebCTRL operator.

In this context, an application program is an abstract representation of a process within a BACnet device, which is executing a particular body of instructions that act upon a particular collection of data structures.

The Program object provides a network-visible view of selected parameters of an application program in the form of properties of the Program object. Some of these properties are specified in the standard and exhibit a consistent behavior across different BACnet devices. The operating state of the process that executes the application program may be viewed and controlled through these standardized properties, which are required for all Program objects.

In addition to these standardized properties, a Program object may also provide vendor-specific properties. These vendor-specific properties may serve as inputs to the program, outputs from the program, or both. However, these vendor-specific properties may not be present at all. If any vendor-specific properties are present, the standard does not define what they are or how they work, as this is specific to the particular application program and vendor.

The link to this device is established in SiteBuilder, and the Object Instance setting in the display input allows the user to link to a specific object within that device.

The BACnet Program Display Object microblock can be used to import multiple properties from a single object, however, to prevent unnecessary network traffic you should only import properties which are actually needed for the intended task. Use the buttons in the Present column to select which properties to get.

Properties

NOTE  Alt+click any value in WebCTRL to view property details, including its expression and editing privilege.