Siemens SINUMERIK 840D sl Programming Manual page 505

Available language scope
Within the definition of the curve table, you have use of the entire NC language.
Note
The following entries are not permitted in curve table definitions:
 Preprocessing stop
 Jumps in the leading axis movement (e.g. on changing transformations)
 Traverse statement for the following axis only
 Reversal of the leading axis, i.e. position of the leading axis must always be unique

Effectiveness of modal operations
All modal statements that are made within the curve table definition are invalid when the
table definition is completed. The part program in which the table definition is made is
therefore before and after the table definition in the same state.
Assignments to R-parameters
Assignments to R-parameters in the table definition are reset after
Example:
Program code
...
R10=5 R11=20
...
CTABDEF
G1 X=10 Y=20 F1000
R10=R11+5
X=R10
CTABEND
...
Activating ASPLINE, BSPLINE, CSPLINE
If an
CTABEND
Immediate activation after
the current axis position before the curve table definition.
Example:
Program code
...
CTABDEF(Y,X,1,0)
X0 Y0
Job Planning
Programming Manual, 03/2013, 6FC5398-2BP40-3BA1
and operation on different program levels.
CTABDEF CTABEND
, or
ASPLINE BSPLINE CSPLINE
, at least one starting point should be programmed before this spline activation.
Comments
; R10=5
; R10=25
; R10=5
is activated within a curve table definition
should be avoided, otherwise the spline will depend on
CTABDEF
Axis couplings
11.2 Curve tables (CTAB)
.
CTABEND
...
CTABDEF
505