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About Parent-Child relationships and execution order

The SFC"Sequential function chart" It can be used to program processes that can be split into steps. The main components of SFC are: - Steps with associated actions - Transitions with associated logic conditions - Directed links between steps and transitions Section allows for editing the period and phase values of parent and child programs. Parent and child programs follow certain rules:

A parent program can be enabled or disabled. If a parent is disabled the child will also be disabled. A child program cannot be disabled.
Parent programs are allowed to move across priorities. Child programs will follow the movement of a parent. Child programs are not allowed to move independently.
When a child program is created or imported, it will inherit the enabled/disabled state of the parent program.
The SFCs are executed at the set cycle period and phase. All parent programs will be executed first and then the children programs will be executed in order.

To understand the last rule, consider the following Cycle example. There are three parent programs, each with a number of child programs. All parents are executed, followed by the children, in order. The actual flow is illustrated below the image.

Parent1
 Parent2
    Parent3
       Parent1_Child1
          Parent1_Child1_Child1
             Parent1_Child2
                Parent1_Child2_Child1
                   Parent2_Child1
                      Parent2_Child1_Child1
                         Parent3_Child1
                            Parent3_Child1_Child1

Parent SFCs should run faster than their children. If this is not the case, the stop condition can be vague. When a child runs slower than its parent it does not stop when the parent stops, but at the child's next execution. This means the parent could execute more, while the child is still running.

A child program is initiated at Phase 0 in respect to its parent.

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