© National Instruments Corporation 2-1 BridgeVIEW User Manual
2
BridgeVIEW Environment
This chapter describes the BridgeVIEW environment. It explains
thebasicconcepts behind G, the programming language upon which
BridgeVIEW isbuilt, the BridgeVIEW Engine Manager, system errors
andevents, the Tag Monitor utility, and the Tag Browser utility. This
chapter also explains how to access online help for BridgeVIEW and
provides an activity that illustrates how to examine the front panel
andblock diagram of a virtual instrument (VI).

What Is G?

G is a programming language, much like various commercial C or BASIC
development languages. However, G is different from those applications
inone important respect. Other programming languages are text-based
languages that create lines of code, while G is a graphical programming
language that creates programs in block diagram form.
You can use G with little programming experience. G engineers and
programmers rely on graphical symbols and data flow rather than textual
language to describe programming actions. Data flow is a programming
system in which nodes execute when they have received all required input
data, and produce output automatically when they have executed.
G has extensive libraries of functions and subroutines for most
programming tasks. BridgeVIEW includes conventional program
development tools for G, so you can set breakpoints, animate program
execution to see how data passes through the program, and single-step
through the diagram to make debugging and program development easier.

How Does G Work?

G includes libraries of functions and development tools designed
specifically for HMI development, data acquisition, and instrument
control. G programs are called virtual instruments (VIs) because their
appearance and operation imitate actual instruments. However, they are
analogous to functions in conventional programming languages.