Siemens SINUMERIK 840D sl Function Manual page 923

Variable addressing
For some NC variables, it is necessary to select "Area no." and/or "Line" or "Column" from the
NC VAR selector. It is possible to select a basic type, i.e. "Area no.", "Line" and "Column" are
preassigned "0". The values of the "Area no.", "Line" and "Column" specified by the NC VAR
selector are checked for a "0" in FB2. If an NC-VAR selector value == "0", the corresponding
value of the FB2 parameter is adopted. To do this, the FB2 parameters "Unit<x>", "Column<x>"
and "Line<x>", with <x> = 1 - 8, must be written before FB2 is called.
Table 13-1
Variables within one group can be combined in a job:
The same rules apply for channels 3 to 10 as for group 1 and group 2 shown in the example.
Note
The number of usable variables can be less than eight when simultaneously reading several
variables of the "String" type.
Declaration of the function
FUNCTION_BLOCK FB2
VAR_INPUT
Basic Functions
Function Manual, 01/2015, 6FC5397-0BP40-5BA2
Parameter match
FB2 parameter
Unit
Column
Line
Group
1 C[1]
2 C[2]
3 V[.]
P3: Basic PLC program for SINUMERIK 840D sl
Area
N B
N B
H[.] ---
13.17 Block descriptions
NC VAR selector
Area no.
Column
Line
O T
O T
--- ---
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