Each POU has a list of local variables, i.e. the POU header. VAR_EXTERNAL references a global variable in the local variables list.
The fields in the variable lists have the following meaning:
- (1) Class is the variable class, e.g. VAR, VAR_GLOBAL etc.
- (2) Identifier is the symbolic name that is used in the program.
- (3) Type: after entering an address, a data type is automatically preselected (e.g. BOOL, INT, STRING). Another type can be selected from the list.
- (4) Initial is the starting value which is assigned to the variable whenever your PLC is started. You can change the value if required.
- (5) Comment is a description of a variable.
NOTE
- Identifiers may not start with a number.
- Identifiers using a special syntax can determine the data type according to the prefix table.
- FP addresses (X0, Y1, etc.) are fixed terms and may not be used as identifiers.
- To add empty lines to the list, press <Shift>+<Return>
- Insert new lines with
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