Bridge User Manual

Chapter 4 Human Machine Interface
BridgeVIEW User Manual 4-2 © National Instruments Corporation
There are several general G programming principles with which you should
be familiar before you build an HMI. These principles are listed below:
• Building basic G front panels and diagrams
• Using controls and indicators
• Using the tag data type
• Using the basic principles of dataflow programming
• Using basic programming constructs such as the Sequence structure
and While Loop
• Using the Time and Dialog VI library
To learn about any of the topics above, see the G Tutorial section of this
manual and complete the activities. For more detailed information, see the
G Programming Reference Manual.
For more advanced HMI programming, you also should know how to use
the G control and indicator attribute nodes and the VI Server functions.
For more information about this topic, see Chapter 13, Front Panel Object
Attributes, and Chapter 15, Application Control.
You might want to divide your HMI into several panels so the operator can
navigate through them using buttons on the screen. The Panel G Wizard
helps you generate the navigation system by automatically generating code
and attaching it to front panel buttons. For more information about the
Panel G Wizard, see Chapter 7, Advanced Application Topics.
How Do You Build an HMI?
To build an HMI, use the graphical controls and indicators to lay out the
user interface objects on the front panel, and a special set of VI libraries
on the block diagram to do the following:
• Read and write tag values
• View and acknowledge alarm states and events
• Display historical and real-time data
• Read tag configuration and security information
• Control the BridgeVIEW system programmatically
• Access and change tag attributes
• Control output tags