ABB ST语言编程(15)

System 800xA Training

13.5Common Mistakes and their Error Messages

13.5.1

Identifier, Constant or Opening Parenthesis Expected

Double clicking on the error message line places the cursor at the end of the statementwith the problem:Usually a missingsemi-colon

(;) at the end of a statement.

13.5.2Variable Name is notUnique

Two variables have been declared with the same name. (Note that this results in two

error one for each non-unique name).

Note also that some other items are classed as ‘variables’ by the system:

- Instance names for function blocks andcontrol modules

- Sequence stepand transitionnames

- Code block names

- Parameters (in function block types and control module types)This means that within any POU all of the above must have unique names.

Chapter13-15