113
FX
3U
/FX
3UC
Series Programmable Controllers
Programming Manual - Basic & Applied Instruction Edition
4 Devices in Detail
4.9 Extension Register [R] and Extension File Register [ER]
1
In
troduct
io
n
2
Ov
e
rv
ie
w
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In
st
ru
ct
ion
Li
st
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D
evi
ce
s
in
De
ta
il
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Speci
fied t
h
e
D
evi
ce &
C
onst
a
nt
6
Bef
o
re
Pr
ogr
a
m
m
ing
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Bas
ic
In
st
ru
cti
o
n
8
FNC0
0
-FNC0
9
P
ro
g
ra
m F
lo
w
9
FNC1
0
-FNC1
9
M
ov
e
&
C
om
par
e
10
FNC
20-
FNC
2
9
Ar
ith.
&
Logi
c
O
per
at
io
n
4.9.6
Functions and operation examples of extension file registers
Extension file registers (ER) are usually used as log data storage destinations and set data storage
destinations.
Extension file registers can be handled only in dedicated instructions shown in the table below. When using
the contents of data in other instructions, transfer them to an extension register of a same device number, and
then use the extension register.
However, note that extension file registers are available only while a memory cassette is mounted.
*1.
Only with a memory cassette mounted, extension file registers are accessible.
1. Relationship between extension file registers and extension registers
Extension file registers and extension registers have the following positional relationship inside the PLC.
Instruction
Description
LOADR(FNC290)
This (transfer) instruction reads data of extension file registers (ER) to extension registers (R).
SAVER(FNC291)
This (transfer) instruction writes data of extension registers (R) to extension file registers (ER) in units of
2048 points (1 sector).Use this instruction to store newly created data of one sector (2048 points) to
extension file registers (ER)
*1
.
INITR(FNC292)
This instruction initializes extension registers (R) and extension file registers (ER)
*1
in units of 2048
points (1 sector).Use this instruction to initialize extension registers (R) and extension file registers
(ER)
*1
before starting to log data by LOGR instruction.
LOGR(FNC293)
This instruction logs specified data, and writes them to extension registers (R)
*1
and extension file
registers (ER).
RWER(FNC294)
This (transfer) instruction writes specified extension registers (R) to extension file registers (ER)
*1
.This
instruction is supported in FX
3UC
PLCs Ver.1.30 or later.Use this instruction to store the contents of any
extension registers (R) to extension file registers (ER)
*1
.
INITER(FNC295)
This instruction initializes extension file registers (ER)
*1
in units of 2048 points (1 sector).This instruction
is supported in FX
3UC
PLCs Ver.1.30 or later.Use this instruction to initialize extension file registers
(ER)
*1
before executing SAVER instruction.
Extension file register (ER)
Extension register (R)
GX Developer
LOGR
instruction
Available in built-in RAM
General-purpose device
(sequence program)
R4096
R0
R32767
SAVER instruction
(in unit of sector)
RWER instruction
(arbitrary number of
points)
Available with a memory
cassette mounted
ER2048
ER0
ER32767
ER4096
R2048
2048
points
2048
points
2048
points
R30720
ER30720
1 sector
All points are
written at one
time
2048
points
2048
points
2048
points
16
sectors
Nonvolatile
memory
LOADR instruction
(in unit of point)
INITR instruction
(initialization)
(in unit of sector)
General
applied
instruction
Programming tool
2048
points
ER6144
INITER instruction
(initialization)
(in unit of sector)
INITER