Data Memory Area (D) - Omron CP1E CPU UNIT SOFTWARE User Manual

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Data Memory Area (D)

Overview
This data area is used for general data storage and manipulation and is accessible only by word (16
bits).
These words retain their contents when the PLC is turned ON or the operating mode is switched
between PROGRAM mode and RUN or MONITOR mode.
Some words in the DM Area can be saved to the built-in EEPROM backup memory using Auxiliary Area
bits. These words are specifically referred to as the backed up words in the DM Area.
Precautions for Safe Use
With an E-type CPU Unit or with an N/NA-type CPU Unit without a Battery, the contents of the
DM Area (D) *, Holding Area (H), the Counter Present Values (C), the status of Counter Comple-
tion Flags (C), and the status of bits in the Auxiliary Area (A) related to clock functions may be
unstable when the power supply is turned ON.
* This does not apply to areas backed up to EEPROM using the DM backup function.
If the DM backup function is being used, be sure to refer to 3-2-4 Initializing I/O Memory at Star-
tup for details.
Notation
D 200
Word number: 200
I/O memory area designator: D
Range
• E-type CPU Units have DM Area addresses ranging from D0 to D2047.
Of these, D0 to D1499 can be backed up in backup memory (built-in EEPROM).
• N/NA-type CPU Units have DM Area addresses ranging from D0 to D8191.
Of these, D0 to D6999 can be backed up in backup memory (built-in EEPROM).
[ E-type CPU Unit ]
· All CPU Units Regardless
of I/O Capacity
D0
Words that can be
to
backed up to backup
memory
D1499
D1500
to
D2047
CP1E CPU Unit Software User's Manual(W480)
[ N/NA-type CPU Unit ]
· N14/20 CPU Unit
D0
to Words that can be backed
up to backup memory
D1199
D1200 DM Fixed Allocation Words
for the Modbus-RTU Easy
to
Master (for Built-in RS-
232C Port)
D1299
D1300
to
D6999
D7000
to
D8191
5 I/O Memory
· N30/40/60 or NA20 CPU Unit
D0
to Words that can be backed
up to backup memory
D1199
DM Fixed Allocation Words
D1200
for the Modbus-RTU Easy
to
Master (for Built-in RS-232C
Port)
D1299
D1300
DM Fixed Allocation Words
for the Modbus-RTU Easy
to
Master (for Serial Option
Port)
D1399
D1400
to
D6999
D7000
to
D8191
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