Actions in ST

Syntax

ACTION name_1 :
  statement_1;
  statement_2;
  ...
  statement_n;
END_ACTION

Bedeutung

an →action within the →SFC network, name_1 must be an →IEC-identifier
Several actions are allowed per SFC network. See the notes under SFC elements in ST how to create/use SFC networks efficiently and correctly.

The action lists one or several ST statements (e.g. block calls or assignments). The control of the actions is expressed by an action qualifier that is specified when associating the action within the step or initial step. See "Evaluating the ST-code including the SFC networks" for information on when a step or initial step is active or inactive and what are the results of the action qualifier on the control of the action.

Restriction

According to the IEC-standard, a Boolean variable can be an action. This is not possible in logi.CAD 3.

The usage of the action is only possible within the current POU.

Note: You are able to use the action (i.e. the name of the action) as a →constant Boolean variable (e.g. for assignments) within the POU. Within cycles in which the action is executed, this variable has the value TRUE (or an equivalent).

Example

ACTION act0 :
  cntStep0 := cntStep0 + 1;
END_ACTION