PLC Programming

What is What in CoDeSys
Entry or exit action
Additional to a step action you can add an entry action and an exit action to a step. An entry action is
executed only once, right after the step has become active. An exit action is executed only once
before the step is deactivated.
A step with entry action is indicated by an "E" in the lower left corner, the exit action by an "X" in the
lower right corner.
The entry and exit action can be implemented in any language. In order to edit an entry or exit action,
doubleclick in the corresponding corner in the step with the mouse.
Example of a step with entry and exit action:
Transition / Transition condition
Between the steps there are so-called transitions.
A transition condition must have the value TRUE or FALSE. Thus it can consist of either a boolean
variable, a boolean address or a boolean constant. It can also contain a series of instructions having a
boolean result, either in ST syntax (e.g. (i