Siemens SINUMERIK 840D sl Programming Manual page 900

Work preparation
3.16 Axis couplings
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
● CTABDEF and CTABEND statement on various program levels.
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 CTABEND.
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 ASPLINE, BSPLINE or CSPLINE is activated within a curve definition table CTABDEF ...
CTABEND, at least a start point should be programmed before this spline activation. Immediate
activation after CTABDEF should be avoided, otherwise the spline will depend on the current
axis position before the curve table definition.
Example:
Program code
...
CTABDEF(Y,X,1,0)
X0 Y0
ASPLINE
X=5 Y=10
900
Comment
;R10=5
;R10=25
;R10=5
Programming Manual, 12/2019, 6FC5398-2EP40-0BA0
NC programming