YOKOGAWA STARDOM FCN-RTU - Execution Order of Control Application

<9. Advanced Engineering >
162
TI 34P02K35-02E
May 31, 2017-00
9.1.4 Execution Order of Control Application
For an FCN-500 or FCN-RTU, the execution order of control has major significance.
This section describes the concept of execution order, as well as how to determine
the execution order and related precautions.
● Synchronization and Execution Order between Multiple Tasks
For a multi-tasking control application, each task executes independently without
synchronization so execution order of the control application between multiple tasks
cannot be considered.
● Execution Order within a Task
The execution order of the control application within a task is according to the order
of assignment to the control task.
In the figure below, three logical POUs are instantiated in control task “Task0.”
In this example, the order of execution is according to the order of assignment:
LogicA → LogicB → LogicC.