|You can add an algorithm to a basic FB type with the New item of the popup menu of the Algorithms node in the Navigation tree.|
|You can delete an
|You can use this
dialog both for adding a new algorithm to a basic FB type or for
editing an existing algorithm. You invoke it by double-clicking an
existing algorithm in the Navigation tree or clicking the Edit
item of its popup menu, or by selecting the New Algorithm item
of the Algorithms popup menu in the Navigation tree. The dialog
|If you use the radio buttons to change languages,
you will see different results depending on the original and new
You can save the changes to the algorithm by pressing the "OK" button, and if no errors are detected, the requested changes (if any) will be made and the dialog will close. If you changed the name of an existing algorithm, references to the algorithm in EC actions will be automatically updated to the new name.
If an error is detected when you press the "OK" button, the dialog does not close, the system "beeps" and an error message appears at the top line of the dialog in the same manner as for EC states.
You can close the dialog without making any changes to the algorithm by pressing the "Cancel" button or the in the upper right corner of the dialog.
|The figure above illustrates an algorithm written in the IEC
61131-3 Structured Text (ST) language. You do not need to enter the
block delimiters ALGORITHM STOP IN
The FBDK performs a token-wise conversion of ST algorithms to Java using regular expressions with minimal parsing of the ST source text. As a result, only a subset of the IEC 61131-3 ST syntax is supported. Limitations include:
|You can write
algorithms in the Java programming language as shown at right.
To avoid namespace conflicts, don't use words in Java literals (double-quoted strings) that are the same as names of variables, events, etc. For instance, if you have an input variable named
However, it would be OK to say