Siemens SINUMERIK 840D sl Function Manual page 1369

Variables in multi-dimensional structures
If variables are selected from multidimensional structures, then the column and/or line
number as well as the area number must be entered so that the variables can be addressed.
The required numbers can be found in the NC variables documentation.
References:
/LIS1/ Lists (Volume 1); Variables
By entering a zero (0) as the block number or the line or column index, it is possible to use
the variable in the S7 PLC as a pointer to these data. When reading or writing these data via
the functions "PUT" and "GET", the optional parameters "UnitX", "ColumnX" and "LineX"
must be filled with the necessary information.
Figure 2-26
Delete variables
Variables are deleted in the window of selected variables by selecting the appropriate
variables (single mouse click) and pressing the "Delete" key. No deletion action is taken with
the doubleclick function. It is possible to select several variables for deletion (see "Selecting
variables").
This action can also be undone under the "Edit" menu item.
Note
Deleting of variables results in a change of the absolute addresses of the pointer structures
to the variables. When changing the variable selection, it is, therefore, absolutely necessary
to generate one or several text files of all user blocksprior to the change. This is the only way
to ensure that the assignment of the variables in FB "GET" or FB "PUT" remains correct,
even after recompilation.
Basic logic functions: PLC basic program solution line (P3 sl)
Function Manual, 11/2006, 6FC5397-0BP10-2BA0
Entry field for line, column and block no.
2.11 General conditions and NC-VAR_Selector
Detailed description
95