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Program Design
Now that you are familiar with many aspects of G programming, you need
to apply that knowledge to develop your own applications. This chapter
suggests some techniques to use when creating programs and offers
programming-style recommendations.
to apply that knowledge to develop your own applications. This chapter
suggests some techniques to use when creating programs and offers
programming-style recommendations.
Use Top-Down Design
When you have a large project to manage, incorporate top-down design.
G has an advantage over other programming languages with respect to
top-down design because you can start with the final user interface then
animate it.
G has an advantage over other programming languages with respect to
top-down design because you can start with the final user interface then
animate it.
Make a List of User Requirements
Create a list of the panels with which the user can interact, the number and
type of controls and indicators for these panels, the need for real-time
analysis, data presentation, and so on. Next, create mock-up front panels
you can show to the prospective users (or manipulate yourself, if you are
the user). Think about and discuss functions and features. Use this
interactive process to redesign the user interface as necessary. You might
need to do some low-level research at this early stage to be certain you can
meet specifications.
type of controls and indicators for these panels, the need for real-time
analysis, data presentation, and so on. Next, create mock-up front panels
you can show to the prospective users (or manipulate yourself, if you are
the user). Think about and discuss functions and features. Use this
interactive process to redesign the user interface as necessary. You might
need to do some low-level research at this early stage to be certain you can
meet specifications.
Design the VI Hierarchy
The power of G lies in the hierarchical nature of VIs. After you create a VI,
you can use it as a subVI in the block diagram of a higher level VI. You can
have an essentially unlimited number of layers in the hierarchy.
you can use it as a subVI in the block diagram of a higher level VI. You can
have an essentially unlimited number of layers in the hierarchy.
Divide the task to be accomplished into manageable, logical pieces. As the
following flowchart illustrates, you can expect several major blocks in one
form or another for every data acquisition system.
following flowchart illustrates, you can expect several major blocks in one
form or another for every data acquisition system.