Data Types¶

When programming in CODESYS, you can use different data types or instances of function blocks. Moreover, you assign a data type to every identifier. The data type defines how much memory CODESYS reserves and how these values are interpreted.

The following group of data types are provided:

Standard data types
Extensions to the IEC 61131-3 standard
User-defined data types

Standard data types ¶

CODESYS supports all IEC 61131-3 data types.

Data Type ‘BOOL’

Integer Data Types

Data Type ‘STRING’

Data Type ‘WSTRING’

Time Data Types

Data Type ‘LTIME’

Extensions to the IEC 61131-3 standard ¶

Data Type ‘UNION’

Data Type ‘BIT’

Special Data Types ‘__UXINT’ and ‘__XWORD’

User-defined data types ¶

You can create user-defined data types in two ways:

DUT object in the POU window
data type in a block in the declaration

Hint

Please note the recommendations for naming and object.

Data Type ‘ARRAY’