Step

A POU written in a Sequential Function Chart consists of a series of steps which are connected with each other through directed connections ().

There are two types of steps.

• The simplified type consists of an and a flag which shows if the step is active. If the action of a step is implemented, then a small triangle appears in upper right corner of the step.
• An consists of a flag and one or more assigned actions or boolean variables. The associated actions appear to the right of the step.