Rockwell Automation Logix5000 Logix5000 Controllers Quick Start - Manual (Page 77)

Publication 1756-QS001E-EN-P - October 2009 77
Program a Project Offline Chapter 5
Enter a Function Block Diagram
A function block diagram lets you visually define the flow of data between instructions. The data flow then
drives the execution order of the instructions.
Item Description
A Sheet divides the diagram into sections without affecting execution. When the routine
executes, all sheets execute.
B Input reference (IREF) reads a value from a tag or set a constant value
C Wire transfers a value between elements
D Instruction produces output values based on input values
E Output reference (OREF) writes a value to a tag
F Output wire connector (OCON) writes a value to one or more ICONs
G Input wire connector (ICON) reads a value from an OCON on the same sheet or a different
sheet in the routine. To read a value from another routine, use an OREF/IREF combination.
A
D
F
E
G
C
B