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

10 CIP Message Communications
10-1 Overview of the CIP Message Com-
munications Service
10-1-1

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.
EtherNet/IP
NJ/NX-series
Controller
EtherNet/IP
10-1-2

Message Communications Service Specifications

Message type
Execution method
Data contents
Communications parameters
Maximum length per
connection
10-2
or host computer
port
CIP command
CIP response
Item
Non-connection type
(UCMM)
Connection type
(class 3)
EtherNet/IP
NJ/NX-series
port
Controller
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 route path specification
502 bytes
•
Using Forward_Open
502 bytes
•
Using Large_Forward_Open
8,192 bytes
NX-series EtherNet/IP Unit User's Manual (W627)