Allen-Bradley LOGIX 5000 User Manual

Chapter 1
Process Control Instructions
60 Rockwell Automation Publication 1756-RM006K-EN-P - November 2018
Before calculating Out, the X axis parameters are scanned. If they are not sorted in
ascending order, the appropriate bit in Status is set and Out remains unchanged.
Also, if XY1Size or XY2Size is invalid, the instruction sets the appropriate bit in
Status and leaves Out unchanged.
The instruction uses this algorithm to calculate Out based on In:
• When In X[1], set Out = Y[1]
• When In > X[XY<n>Size], set Out = Y[XY<n>Size]
• When X[n] < In X[n+1], calculate Out = ((Y[n+1]-Yn)/ (X[n+1]-
Xn))*(In-Xn)+Yn
Affects Math Status Flags
No
Major/Minor Fault
None specific to this instruction. See Common Attributes for operand-related
faults.
Execution
Function Block
Condition Function Block Action
Prescan EnableIn and EnableOut bits are cleared to false.
Tag.EnableIn is false EnableIn and EnableOut bits are cleared to false.
Tag.EnableIn is true EnableIn and EnableOut bits are set to true. The instruction executes.
Instruction first run N/A
Instruction first scan N/A
Postscan EnableIn and EnableOut bits are set to true. The instruction executes.
Structured Text
Condition/State Action Taken
Prescan See Prescan in the Function Block table.
Normal Execution See Tag.EnableIn is true in the Function Block table.
Postscan See Postscan in the Function Block table.

Allen-Bradley LOGIX 5000 Specifications

General

Brand	Allen-Bradley
Model	LOGIX 5000
Category	Controller
Language	English