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

4.2.6

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 syntaxes such as selection branch by conditional syntaxes or repetitions by iterative
syntaxes can be described in the ST language, as in the high-level language such as C
language. Clear and simple programs can be written by using these syntaxes.
(2) Structured ladder: (ladder diagram)
The structured ladder language is a graphic language developed based on the relay ladder
programming technique. Since it can be understood intuitively, it is commonly used for the
sequence programming.
Ladders always start from the base line on the left.
A program written in the structured ladder language is composed of contacts, coils, function
blocks, and functions. These elements are connected by vertical and horizontal lines.
4.2.6 Programming languages for POUs
4.2 POUs
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