SFC macro steps
"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
chart, a part of the chart that begins with a step and ends with a step. The
body of the macro-step must be declared in the same program. The body of a
macro-step begins with a special "begin" step with no link before, and ends with
a special "end" step with no link after. The symbol of the macros step in the
main chart has double horizontal lines:
A: Main Chart
B: Body of the macro-step
1: Macro step symbol
2: "Begin" step
3: "End" step
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- The macro-step symbol and the beginning step must have
the same number.
- The body of the macro-step must have no link with other parts of the main
diagram (must be connected).
- A macro step is not a "sub program". It is just a drawing features that enables you to make clearer charts. You must never insert several macro-step symbols referring to the same macro-step body.
- The macro-step symbol and the beginning step must have
the same number.