Rockwell Automation 1747-PT1, D1747NP002 Hand-Held Terminal - Manual (Page 317)

Instructions
Chapter 23
Bit Shift, FIFO, and LIFO
23–5
If you wish to shift more than one bit per scan, you must create a loop using
jump (JMP) and label (LBL) instructions.
SLC 5/02 Processors Only
FIFO Load, FIFO Unload FFL, FFU Output Instructions
(FFL) (FFU)
(EN)
(DN)
(EM)
FFL
FIFO LOAD
Source
N7:10
FIFO #N7:12
Control R6:0
Length 34
Position 0
(EU)
(DN)
(EM)
FFU
FIFO UNLOAD
FIFO
#N7:12
Dest N7:11
Control R6:0
Length 34
Position 0
F1 F2 F3 F4 F5
ZOOM on FFL –(FFL)– 2.3.0.0.2
NAME: FIFO LOAD
SOURCE: N7:10 LENGTH: 34
FIFO: #N7:12 POSITION:0
CONTROL: R6:0
EN EU DN EM
0 0 0 0
EDT_DAT
HHT Ladder Display:
HHT Zoom Display:
Ladder Diagrams and APS Displays:
(online monitor mode)
F1 F2 F3 F4 F5
ZOOM on FFU –(FFU)– 2.4.0.0.2
NAME: FIFO UNLOAD
FIFO: #N7:12 LENGTH: 34
DEST: N7:11 POSITION:0
CONTROL: R6:0
EN EU DN EM
0 0 0 0
EDT_DAT
FFL and FFU instructions are used in pairs. The FFL instruction loads words
into a user-created file called a FIFO stack. The FFU instruction unloads
words from the FIFO stack, in the same order as they were entered.
FIFO and LIFO instruction applications include assembly/transfer lines,
inventory control, and system diagnostics.
FIFO Load (FFL), FIFO
Unload (FFU)