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Artificial data dependency, Artificial data dependency -15, End of activity 12-3. artificial data dependency – National Instruments BridgeVIEW User Manual

Page 278

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Chapter 12

Case and Sequence Structures and the Formula Node

© National Instruments Corporation

12-15

BridgeVIEW User Manual

5.

Save the VI as

Equations.vi

in the

BridgeVIEW/Activity

directory.

End of Activity 12-3.

Artificial Data Dependency

Nodes not connected by a wire can execute in any order. Nodes do not
necessarily execute in left-to-right, top-to-bottom order. A Sequence
structure is one way to control execution order when natural data
dependency does not exist.

Another way to control execution order is to create and artificial data
dependency, a condition in which the arrival of data rather than its value
triggers execution of an object. The receiver may not actually use the data
internally. The advantage of artificial dependency is that all of the nodes
are visible at one level, although, in some cases, the confusion created by
the artificial links between the nodes can be a disadvantage.

You can open the

Timing Template (data dep).vi

from

G Examples\General\structs.llb

to see how the

Timing

Template

has been altered to use artificial data dependency rather

than a sequence structure.