Developing an application for a real-time controller is similar to developing an application for a PC. However, real-time applications typically employ particular programming practices in order to adhere to strict timing specifications.
Before you start implementing a real-time application design, make sure you have a well-planned design. Refer to
Designing a Real-Time Application
for help designing your application.
A real-time application is a VI targeted to a real-time controller in SystemDesigner that contains some deterministic code. Real-time VIs contain unique real-time nodes that help you write deterministic code in addition to many of the same nodes that are available in VIs targeted to a PC.
Complete the following steps to implement your real-time application design.
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Create code—To analyze or process data in a real-time application, you must create code on the diagram of a VI targeted to a real-time controller in SystemDesigner.
The code you write is entirely dependent on the goals and requirements of your application.
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Place deterministic tasks in
Timed Loops
—Timed Loops
execute the code you place within them at a higher priority than code outside of a
Timed Loop. You must place code that you want to execute deterministically in a
Timed Loop.
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Organize deterministic and non-deterministic tasks—Separating deterministic code from non-deterministic code helps ensure that deterministic tasks reserve enough processor resources and avoid excessive jitter.
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Transfer data within, to, and from a real-time application—Real-time applications typically require communication between loops or subVIs within the real-time application and with other applications running on a PC or FPGA. You can use data communication nodes to transfer data within, to, and from a real-time application.
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Eliminate common sources of jitter—You can introduce jitter into your application in a variety of ways. However, you can follow a few simple strategies to identify and eliminate the more common sources of jitter.
After you finish implementing your application design, you can
deploy and test your application.