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"Queue" tag

RT code

Use a queue to send messages and data between two or more parallel process loops contained within a VI or other VIs. Queues also serve as the foundation for the "Queued State Machine" design pattern.
Queue-based state machines excel at implementing system control, data measurement and processing, and other tasks to respond to inputs from the surrounding physical system and user interface. Learn about three popular design patterns: queued state machine (QSM), queued message handler (QMH), and event-driven producer-consumer loops.
Example of a complete RT system controller based on the Queued Message Handler (QMH) design pattern with multiple parallel task loops implementing behaviors with queued state machines (QSMs), various inter-process communication techniques (queues and local variables), and inter-target communication techniques (network-published shared variables (NPSVs) and network streams). The PC host human-machine interface (HMI) can remotely connect to the system through the network, monitor the status of the security system, and control it remotely.
Create a responsive user interface based on two loops operating in parallel: the "producer" loop event structure responds immediately to user interactions such as button clicks and mouse movements that send commands through a queue to the "consumer" loop which performs the required tasks. Separating the state machine into two loops allows the user interface to remain responsive should a consumer task require an unusual amount of time or must wait for a shared resource to become available.