and Workarounds[Back to FBDK Help]
and Workarounds| This table contains a list of known bugs and recommended workarounds in the current release of the FBDK. | ||
| No. | Bug Description | Recommended Workaround |
|---|---|---|
| 1 | IEC 61131-3 strong data typing is not enforced and IEC 61131-3 type conversion functions are not available in mathematical expressions of ST algorithms. Instead, each expression is translated token-by-token from ST notation to Java. Hence, expressions are evaluated according to the rules for Java rather than the strongly typed rules for IEC 61131-3. | In general, just be aware that evaluation of ST expressions compiled in the FBDK will follow the rules for operators given in the Java Tutorial. The FBEditor will automatically insert a cast operator to force the result of an expression to the required type for assignment to a variable with the ST ":=" operator. |
| 2 | Accessors for structured variables are not correctly generated. | Fix the accessor bugs manually in the generated Java source file. |
| 3 | Bit string literals in ST expressions, e.g., 16#FE, are not
correctly translated to Java. |
Another consequence of the weak ST parsing. It
does, however, work in variable initializations and graphical
connections. The Java notation 0xFE may work in ST
expressions but is not tested. |
| 4 | FBDK does not recognize the DOCTYPE element in XML files unless it has a space before the closing delimiter; for instance,<!DOCTYPE FBType SYSTEM "http://www.holobloc.com/xml/
LibraryElement.dtd">is not recognized as having proper syntax, while <!DOCTYPE FBType SYSTEM "http://www.holobloc.com/xml/
LibraryElement.dtd" >is recognized. |
Add the extra space manually before opening the file in FBDK. |