Using Cip Communications Instructions - Omron CJ1W-EIP21 Operation Manuals

8 Message Communications
Instruction Name
Open CIP Class
CIPOpen
3 Connection
Read Variable
CIPRead Class 3 Explicit
Write Variable
CIPWrite Class 3 Explicit
Send Explicit
Message Class
CIPSend 3
Close CIP Class
CIPClose
3 Connection
8-2-3

Using CIP Communications Instructions

CIP message communications include the following processes. If CIP class 3 connections are used, the
open and close processes are required before and after the data is sent and received.
Process
*1 Execute this process before you use a CIP message. Open pro-
Open process
cessing is continued until a connection is established.
(only for CIP
class 3 connec-
tions)
Sending and This process is used to read and write data for specified variables
receiving vari- with the Network Publish attributes.
*2
able data
Sending CIP You can set the required CIP command.
commands
Close process This process closes the connection.
(only for CIP
class 3 connec-
tions)
*1 There can be up to 32 handles at the same time from opening connections. Even if a connection is broken for a timeout,
the handle is not released. Execute the CIPClose instruction.
*2 Addresses in memory for CJ-series Units (e.g., D0000) cannot be specified directly. To access memory for CJ-series
Units, access a variable with an AT specification.
8-4
Description
This instruction opens a CIP class 3 connection with the specified
remote node.
Reads the value of a variable with a Network Publish attribute from
the specified remote Controller on the CIP network and stores the
value in a variable at the local Controller.
Writes the value of a variable at the local controller to a variable
with a Network Publish attribute at the specified remote Controller
on the CIP network.
Sends a specified class-3 CIP command to the specified remote
Controller on the CIP network.
Refer to 8-2-9 Response Codes and 8-3 CIP Objects Sent to the
EtherNet/IP Unit for information on the service codes and response
codes that are used with the NJ-series CPU Units.
This instruction closes the CIP class 3 connection that is specified
by the handle.
Description
CJ-series EtherNet/IP Units Operation Manual for NJ-series CPU Unit (W495)
Communica-
tions method
CIP class 3 con-
nection mes-
sage
Instruction
CIPOpen
CIPUCMMRead
CIPUCMMWrite
CIPRead
CIPWrite
CIPUCMMSend
CIPSend
CIPClose