SA0034: Enumeration variables with incorrect assignment

Function	Determines values that are assigned to an enumeration variable. Only defined enumeration constants may be assigned to an enumeration variable.
Reason	An enumeration type variable should only have the intended values, otherwise code that uses that variable may not work correctly. We recommend using only enumerations that have the {attribute 'strict'}. In this case the compiler checks the correct use of the enumeration components.
Importance	High

Sample:

Enumeration E_Color:

TYPE E_Color :
(
    eRed   := 1,
    eBlue  := 2,
    eGreen := 3 
);
END_TYPE

MAIN program:

PROGRAM MAIN
VAR
    eColor : E_Color;
END_VAR

eColor := E_Color.eRed;
eColor := eBlue;
eColor := 1;                     // => SA0034