Cip Communication Server Function; Cip Message Structure For Accessing Cip Objects - Omron NX-series User Manual

8-2

CIP Communication Server Function

When receiving a CIP message from an external device, the CIP Safety-compliant Control Unit exe-
cutes services for specified self-contained objects.
This function is called, the "CIP Communication Server function".
This section describes information on CIP messages structure along with information about how to
use CIP messages. The CIP Communication Server function allows users to read and write CIP ob-
jects as well as to read and write values of variables by issuing a CIP message to the CIP Safety-
compliant Communication Control Unit from a program that runs on a computer or a controller.
The variable to access
is specified in the
request path of the
CIP object or the
explicit message
to read or write data.
CIP Safety-compliant
Communication Control Unit
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CIP Message Structure for Accessing CIP Objects

This section shows how to specify messages to access CIP objects.
The CIP objects to be accessed are expressed by connecting the segments
defined in the CIP Common Specifications in the request path field in a CIP explicit message.
Example: Performing the Reset service (0x05) to the Instance (01 hex) of the Identity object (class: 01
hex)
CIP Explicit Message (Request)
Service
Code
(0x05)
Specify the service
code to perform. (*1)
*1. Refer to 8-4 CIP Object Services on page 8 - 11 for information about the service codes.
NX-series Communication Control Unit Built-in Function User's Manual (Z396)
Request
Response
Variable
Request
[1]
Path Length
(20 01)
(02)
Logical Segment
(Class ID)
Specify the Class ID and
Instance ID to access.
8 CIP Message Communications
The writing results of the
specified CIP object or
variable, or the value that
was read from the
specified CIP object or
variable are stored
in the response.
Request
Response
Request Path
[2]
(24 01)
Logical Segment
(Instance ID)
Computer
Controller
Variable
Request
Service
Data
(num of
elem)
Specify the Request Data
according to the service.
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