Overview Of The Cip Message Communications Service; Message Communications Service Specifications - Omron NJ Series User Manual

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Overview of the CIP Message Com-
munications Service
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Overview of the CIP Message Communications Service

CIP commands can be sent to devices on the EtherNet/IP network whenever they are required.
You execute CIP_SEND instructions in a program in the NJ/NX-series CPU Unit to send CIP com-
mands, such as those to read and write data and to receive the responses.
You can use CIP messages from the client to read and write memory in the Controller with the server
without adding any special programming to the user program of the Controller with the server.
NJ/NX-series
EtherNet/IP
Controller
EtherNet/IP
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Message Communications Service Specifications

Message type
Execution method
Data contents
Communications parameters
Maximum length per
connection
NJ/NX-series CPU Unit Built-in EtherNet/IP Port User's Manual (W506)
Built-in
or host computer
port
CIP command
CIP response
Item
Non-connection type
(UCMM)
Connection type
(class 3)
8 CIP Message Communications
Built-in
NJ/NX-series
EtherNet/IP
Controller
port
Specification
Either of the following can be selected.
CIP UCMM connectionless messages
CIP class 3 connection messages
CIPSend (Send Explicit Message Class 3) instruction or CI-
PUCMMSend (Send Explicit Message UCMM) instruction
Sending required CIP commands and receiving responses
Message type, timeout value, and root path specification
502 bytes
•
Using Forward_Open
502 bytes
•
Using Large_Forward_Open
NX701 CPU Unit: 8192 bytes
NX102 CPU Unit: 1994 bytes
NX1P2 CPU Unit: 1994 bytes
NJ-series CPU Unit: 1994 bytes
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