LABELS

Statement - Destination of a Jump instruction.

Remarks

Labels are used as a destination of a jump instruction in FDB, FFLD, or IL language.

Labels and jumps cannot be used in structured ST Language.

  • A label must be represented by a unique name, followed by a colon :.
  • In all languages, it is not mandatory that a label is a target of a jump instruction.
    • Use label for marking parts of the programs in order to increase its readability.

FBD Language Example

  • Labels can be inserted anywhere in the diagram.
  • They are connected to nothing.

In this example, the DTAt block is not called if bEnable is TRUE.

FFLD Language Example

  • A label must identify a rung.
  • It is shown on the left side of the rung.

In Figure 1, Network #6 is skipped if IN1 is TRUE.

Figure 1: Example: FFLD jump

IL Language Example

Not available.

ST Language Example

Not available.

See Also