Omron SYSMAC CJ1W-EIP21 User Manual
Page 276
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Receiving Explicit Messages
Section 9-2
I/O Memory Read/Write for CPU Units
Note With a EtherNet/IP Unit or built-in EtherNet/IP port with unit version 2.0 or
later, the PLC object class ID is C4 hex. (With unit version 1.0, the PLC object
class ID is F2 hex.)
The commands and responses for the explicit messages that can be sent and
received are described on the following pages.
In the following command and response formats, all boxes represent 1 byte
each.
Service
Service
code
Class ID
Instance ID
Request
service
data
Contents
Byte Data Read
1C Hex
C4 Hex
(2F Hex)
(See note.)
Specifies
area (01 Hex
to 14 Hex)
Address, No.
of read bytes
Reads the specified node data in byte units.
The word data is read in order, from high to
low bytes.
Read data: 200 bytes max.
Word Data
Read
1D Hex
Address, No.
of read
words
Reads the specified node data in word
units. The word data is read in order, from
high to low bytes.
Read data: 200 bytes max.
Byte Data Write
1E Hex
Address,
byte data
Writes the specified node data in byte units.
The word data is specified in order, from
high to low bytes.
Write data: 200 bytes max.
Word Data Write 1F Hex
Address
word data
Writes the specified node data in word
units. The word data is specified in order,
from high to low bytes.
Write data: 200 bytes max.