Rockwell Automation GMLC Reference Manual - Manual (Page 442)

Publication GMLC-5.2 - November 1999
On Expression 405
On Expression
Use the On Expression block to:
•
Evaluate a mathematical expression and make a logical decision
based on the expression’s value (If Expression Type).
• Pause execution of a task or program until the value of a
mathematical expression is greater than or less than zero (Wait For
Expression Type).
The On Expression block resides on the Main Palette.
Wait for Expression
The Wait for Expression type pauses the program until the value of a
mathematical expression meets the specified criteria. See the Expression
Builder chapter in this manual for information on constructing
expressions.
When you select the Wait For Expression type, the block has a single exit
node.
If Expression
The If Expression type evaluates a mathematical expression and makes a
logical decision based on its value. Program flow branches to the true
node (at the top of the block) if the value of the expression does not equal
zero, and to the false node (at the bottom of the block) if the expression
equals zero. Enter the desired expression to evaluate.
Build Table
Use the Build Table block to build time and position cam profiles, and
arrays of user variables. Construct a table of values by entering a value or
expression for each item in the table, or by copying points from a
spreadsheet.