ControlLogix Array Referencing

Rockwell said:

You cannot nest more than one pair of brackets [ ] when using indirect addressing. For example:
Address[Position] would work, but Address[Array[Position]] would not work. If you are using tags equated to arrays and you need to use the various elements of the array within the indirect address, you will have to create an alias which references that element and use that instead. As a rule just remember only one set of brackets in any address/expression

On FAL and other File type instructions, you are better off letting the FILE ADDRESS always start at word zero of the array. If you do not start at word zero you will have to use an alias point to which starting word of the file you want the instruction to access when the position is zero.

If an array of control elements are used, you will need to also have aliases pointing to which .POS element of which one this instruction is using as the tagname within the [brackets]. If individual control tags (not arrays) are used, the aliases are not necessary and you should create the desired tag as a control element while programming the instruction. If the control tags are created first in the tag editor, the SW may get confused and think what you are entering is a new tag name not one that already exists.

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