408 Rockwell Automation Publication 1756-RM003N-EN-P - October 2011
Chapter 9 Array (File)/Shift Instructions (BSL, BSR, FFL, FFU, LFL, LFU)
Condition Relay Ladder Action
Postscan The rung-condition-out is set to false.
Rung-condition-in is true.
Examine .EN bit.
.EN Bit = 1
.EN Bit = 0
End
.DN bit is set.
Shift array one position to the right.
Rung-condition-out is set
to true.
.DN bit is set.
.POS = .LEN
.LEN = 0
Yes
No
.LEN < 0
Yes
No
Source
bit
.UL Bit
Array
Examine source bit.
.Source Bit = 1
.Source Bit = 0
.UL bit remains set.
.UL bit is set.
.ER bit is set.
.EN Bit is set.