Rockwell Automation GMLC Reference Manual - Manual (Page 357)

Publication GMLC-5.2 - November 1999
320 I/O and Event Blocks
Event Action Computations
Watch position actions are fast because the event action block (connected
to the top (true) node of the Watch Control block) is completely evaluated
when the Watch Control block executes, and is ready for instant response
when the watch position event occurs. Therefore, any variables used in
the event action block are evaluated once, immediately when the Watch
Control block is executed. The event action block should not use any
expressions that depend on the occurrence of the watch position event.
Enable Dedicated and Configured Input Event/Action
The Watch Control block, with Enable Event/Action type and Dedicated
or Configured class selected, sets up an input event and a specific action
that happens when the input event occurs. This allows the input event to
directly cause an action when triggered.
To specify the action that happens when the input event occurs, one of the
blocks shown below must be directly connected to the top (true) node of
the Watch Control block:
• Gear Axes
• Position Lock Cam
• Redefine Position
• Move Axis
• Equation
• Interrupt SLC