Rockwell Automation Logix5000 Logix5000 Controllers Quick Start - Manual (Page 40)

40 Publication 1756-QS001E-EN-P - October 2009
Chapter 2 Organize a Project
Create User-defined Data Types
User-defined data types let you organize your data to match your machine or process. This streamlines
program development and creates self-documenting code that is easier to maintain.
Item Description
A Tag stores data. There is no fixed data table or numeric format for data addresses. The tag
name is the address. You create the tags that you want to use.
B Data type defines the type of data that a tag stores, such as a bit, integer, floating-point
value, or string.
C Array defines a block of data (file). The entire block uses the same data type. It can have 1,
2, or 3 dimensions.
D Structure combines a group of data types into a re-usable format (template for tags). Use a
structure as the basis for multiple tags with the same data layout.
E Member describes an individual piece of data within a structure.
F User-defined data type defines your own data structure. A user-defined data type stores all
the data related to a specific aspect of your system. This keeps related data together and
easy to locate, regardless of its data type.
A
D
F
E
C
B