Mitsubishi Electric MELSEC FX3U Programming Manual page 145

FX /FX /FX Series Programmable Controllers
3G 3U 3UC
Programming Manual - Basic & Applied Instruction Edition
1. Relationship between extension file registers and extension registers
Extension file registers and extension registers have the following positional relationship inside the PLC.
a) FX /FX
3U 3UC
General-purpose device
(sequence program)
INITR instruction
(initialization)
(sector units)
b) FX PLCs
3G
General-purpose device
(sequence program)
PLCs
Extension register (R)
Available in built-in RAM
R0
2048
points
R2048
2048
General
points
applied
instruction R4096
2048
points
INITER
LOGR
instruction
R30720
R32767
GX Developer
Extension register (R)
Available in built-in RAM
R0
General
applied
instruction
R23999
4.10 Extension Register [R] and Extension File Register [ER]
Extension file register (ER)
Available with a memory
SAVER instruction
(sector units)
RWER instruction
(point units)
ER0
ER2048
LOADR instruction
(point units)
ER4096
ER6144
INITER instruction
(initialization)
(sector units)
All points are
written at one
time
ER30720
ER32767
Programming tool
RWER instruction
(arbitrary number of points)
LOADR instruction
(point units)
All points are
written at one
time
Programming tool
GX Developer
4 Devices in Detail
cassette mounted
2048
1 sector
points
2048
points
2048
points
2048
points
16
sectors
Nonvolatile
memory
Extension file register (ER)
Available in attached memory
cassette or built-in EEPROM
ER0
ER23999
Nonvolatile
memory
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