Omron CJ1W-EIP21 - 10-2010 Operation Manual page 278

Receiving Explicit Messages
I/O Memory Read/Write for CPU Units
Service Service
code
Byte Data Read 1C Hex
Word Data 1D Hex
Read
Byte Data Write 1E Hex
Word Data Write 1F Hex
250
Class ID Instance ID
C4 Hex Specifies
(2F Hex) area (01 Hex
(See note.) to 14 Hex)
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.
Request
service
data
Address, No. Reads the specified node data in byte units.
of read bytes The word data is read in order, from high to
low bytes.
Read data: 200 bytes max.
Address, No. Reads the specified node data in word
of read units. The word data is read in order, from
words high to low bytes.
Read data: 200 bytes max.
Address, Writes the specified node data in byte units.
byte data The word data is specified in order, from
high to low bytes.
Write data: 200 bytes max.
Address Writes the specified node data in word
word data units. The word data is specified in order,
from high to low bytes.
Write data: 200 bytes max.
Section 9-2
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