Rockwell Automation 1761-HHP-B30 MicroLogix 1000 with Hand-Held Programmer (HHP) - Manual (Page 211)

Chapter 11
Using Data Handling Instructions
11–28
LFL and LFU instructions are used in pairs. The LFL instruction loads
words into a user-created file called a LIFO stack. The LFU instruction
unloads words from the LIFO stack in the opposite order as they were
entered.
Entering the Instructions
You enter the instructions from within the program monitor functional area.
While entering the LFL instruction, you see these screens:
P 0 0 0 L F L S R C
N 1 0
P 0 0 0 L F L L I F O
# N 1 2
P 0 0 0 L F L C T R L
R 0
P 0 0 0 L F L L E N
* * * * 3 4
P 0 0 0 L F L P O S
* * * * * 9
LIFO Load (LFL) and
LIFO Unload (LFU)
(EN)
(DN)
(EM)
LFL
LIFO LOAD
Source
N7:10
LIFO #N7:12
Control R6:0
Length 34
Position 9
(EU)
(DN)
(EM)
LFU
LIFO UNLOAD
LIFO
#N7:12
Dest N7:11
Control R6:0
Length 34
Position 9
False
61.13
True
33.67 LFL
64.20 35.08 LFU
Execution Times (
µ
sec) when:
(EN)
(DN)
(EM)
(EU)
(DN)
Ladder representation:
5
To enter the function code, press:
ENT
1
FUN
1