Allen-Bradley Logix5000 Reference Manual page 433

Example:
When enabled, the LFU instruction unloads array_dint[5] into value_2.
Before LIFO unload
array_dint[0] 00000
11111
22222
33333
44444
array_dint[5] 55555
00000
00000
00000
00000
Rockwell Automation Publication 1756-RM003N-EN-P - October 2011
Array (File)/Shift Instructions (BSL, BSR, FFL, FFU, LFL, LFU)
After LIFO unload
00000
11111
22222
33333
44444
00000
control_1.pos = 6 00000
00000
00000
00000
Chapter 9
control_1.pos = 5
value_2 = 55555
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