Differences between Functions and Function Blocks

It is important to clearly understand what is different between functions and function blocks.

• A  Function A function calculates a result according to the current value of its inputs. A function has no internal data and is not linked to declared instances. is called once and it performs an action.
  • This is synchronous Combines an axis or axes group (as slave) with an axis as master. The slave executes its path with synchronization to the progress of the master. This is linked to a one dimension source for synchronization..
• A  Function Block A function block groups an algorithm and a set of private data. It has inputs and outputs. (FB) is an instance that has its own set of data.
  • An FB maintains its own, internal machine The complete assembly of all connected parts or devices, of which at least one is movable. state and often has an output to indicate when the work is done.
  • An FB is asynchronous.
  • The best way to work with a function block is to call it during multiple scan.
    • This triggers the action the first time, then monitor the status of this action, especially via the Done output.

See Also

• Function Call
• Call a Function Block