A DUT (Data Unit Type) declares a user-specific data type.
Symbol:
-
DUT -
Enumeration with text list support
You can add this kind of object below the application or in the POUs view.
When the object is created, the “Add DUT” dialog opens. There you can configure the new data type and choose from the constructs (structure, enumeration, alias, and union).
Syntax for the declaration of user-defined data types
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TYPE <identifier> : <data type declaration> END_TYPE |
DUT construct A user-defined data type declaration is placed between the brackets TYPE and END_TYPE. |
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TYPE <identifier> : STRUCT <member declaration> END_STRUCT END_TYPE |
A structure encloses its members with STRUCT and END_STRUCT. Any number of members can be declared, but at least two. STRUCT |
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TYPE <identifier> : ( <list of members> ) <base data type> := <initialization> ; END_TYPE |
An enumeration is a comma-separated list of member names in round brackets. All members have the same data type. An enumeration can also have a text list assigned to it. This is used to localize the values of the enumeration. As a result, the object also has a localization view. Enumeration |
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TYPE <identifier> : <data type name> ; END_TYPE |
An alias is an alternative identifier. Alias |
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TYPE <identifier> : UNION <member declaration> END_UNION END_TYPE |
A union encloses its members with UNION and END_UNION. It is a data type with several members which share a the same memory location. UNION |
Example
Declaration of the structure S_POLYGONLINE with partial initialization of members
TYPE S_POLYGONLINE :
STRUCT
aiStart : ARRAY[1..2] OF INT := [-99, -99];
aiPoint1 : ARRAY[1..2] OF INT;
aiPoint2 : ARRAY[1..2] OF INT;
aiPoint3 : ARRAY[1..2] OF INT;
aiPoint4 : ARRAY[1..2] OF INT;
aiEnd : ARRAY[1..2] OF INT := [99, 99];
END_STRUCT
END_TYPE
Declaration of the structure S_PENTAGON as an extension of S_POLYGONLINE
TYPE S_PENTAGON EXTENDS S_POLYGONLINE :
STRUCT
aiPoint5 : ARRAY[1..2] OF INT;
END_STRUCT
END_TYPE
Example
Declaration of the enumeration E_TRAFFICSIGNAL
{attribute 'qualified_only'}
{attribute 'strict'}
TYPE E_TRAFFICSIGNAL :
(
eRed,
eYellow,
eGreen := 10
);
END_TYPE
Enumeration with text list support in the localization view
The 
“Textual View” and 
“Localization View” buttons are located on the right edge of the editor. Click the buttons to toggle
between the views.
Example
Declaration of an alias
TYPE A_MESSAGE : STRING[50]; END_TYPE
Example
Declaration of a UNION
TYPE U_DATA :
UNION
lrA : LREAL;
liA : LINT;
dwA : DWORD;
END_UNION
END_TYPE