An instance of this type provides sampling of an input variable IN whose type is specified by the xxx suffix in the FB type name. Upon the occurrence of a REQ event:

• If the value of the OUT variable is already equal to that of the IN variable, no action is taken.
• Otherwise, the value of OUT is copied from the value of IN, and an event is issued at the CNF output.

These FB types are found in the src/sample folder of the FBDK.

An example of this family of FB types is shown below, where xxx = REAL.