Programming Languages For Pous - Mitsubishi Electric MELSEC Q Series Structured Programming Manual

4.2.7

Programming languages for POUs

Two types of programming language are available for programs of POU.
The following explains the features of each programming language.
(1) ST: Structured text
Control syntax such as selection branch by conditional syntax or repetitions by iterative
syntax can be described in the structured text language, as in the high-level language such
as C language. Clear and simple programs can be written by using these syntax.
(2) Structured ladder/FBD: (ladder diagram)
The structured ladder or FBD is a graphical language developed based on the relay ladder
programming technique. They are commonly used for the sequence programming because
they can be understood intuitively.
• Structured ladder
• FBD
4.2.7 Programming languages for POUs
4.2 POUs
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