Allen-Bradley Logix5000 Reference Manual page 487

Arithmetic Status Flags:
Fault Conditions:
Condition
Prescan
Rung-condition-in is false
Rung-condition-in is true.
No
Goto
End
Postscan
Not affected
A major fault will occur if
Main routine contains a RET instruction
Execution:
Relay Ladder Action
The rung-condition-out is set to false.
The controller executes the subroutine once.
If recursive FOR instruction0s exist to the same subroutine, the subroutine is prescanned only the
first time. If multiple FOR instructions exist (non-recursive) to the same subroutine, the subroutine
is prescanned each time.
The rung-condition-out is set to false.
No
Index ≤ Terminal Value
Yes
Yes
Execute Routine
index =(index + step_size)
The rung-condition-out is set to false.
Rockwell Automation Publication 1756-RM003N-EN-P - October 2011
For/Break Instructions (FOR, FOR...DO, BRK, EXIT, RET)
Index = initial_value
Step size < 0
Yes
No
Index ≥ Terminal Value
Fault Type Fault Code
4 31
Goto
End
End
Rung-condition-out is set to true.
End
Chapter 12
487