8-4-2
Examples of Variable Specifications
Segments are joined to form the request path that specifies the variable to access.
Data Segment
Logical Segment
(Member ID)(ANSI Extended Symbol Segment)
Specify the variable name and
the member name.
Specify the array index.
8-4-3
Logical Segment
A logical segment is used to give the range of the CIP Object or variable (array) in the request path.
Logi
cal Type
7 6 5 4 3 2 1 0
0
0 1
Logical Forma
t
Segme
nt Format Bits
Logical Type
Meaning
4 3 2
0 0 0 Class ID
0 0 1 Instance ID
0 1 0 Member ID
0 1 1 Connection Point
1 0 0 Attribute ID
1 0 1 Special (Do not use the logical addressing definition for the Logical Format.)
1 1 0 Service ID (Do not use the logical addressing definition for the Logical Format.)
1 1 1 Reserved
Logical
Format
Meaning
1 0
0 0 8 bit logical address
0 1 16 bit logical address
1 0 32 bit logical address
1 1 Reserved
An 8-bit or 16-bit logical address can be used for the class ID and attribute ID.
An 8-bit,16-bit, or 32-bit logical address can be used for the instance ID.
8-4-4
Data Segment
A data segment is used to give the specified variable name in the request path.
8 CIP Message Communications
8-42
NJ/NX-series CPU Unit Built-in EtherNet/IP Port User’s Manual (W506)