Siemens SINUMERIK 840D sl Programming Manual page 395

Example of the use of CTABSSV and CTABSEV
Determining the curve segment belonging to master value X = 30.
N10 DEF REAL STARTPOS
N20 DEF REAL ENDPOS
N30 DEF REAL GRADIENT
...
N100 CTABDEF(Y,X,1,0)
N110 X0 Y0
N120 X20 Y10
N130 X40 Y40
N140 X60 Y10
N150 X80 Y0
N160 CTABEND
...
N200 STARTPOS =
CTABSSV(30.0, 1, GRADIENT)
...
N210 ENDPOS =
CTABSEV(30.0, 1, GRADIENT)
Reading table positions, CTAB, CTABINV
CTABINV therefore requires an approximate value (approxLV) for the expected leading
value. CTABINV returns the leading value that is closest to the approximate value. The
approximate value can be the leading value from the previous interpolation cycle.
Job planning
Programming Manual, 03/2006 Edition, 6FC5398-2BP10-1BA0
;Begin of the table definition
;Starting position 1st table segment
;End position of the 1st table segment =
;Start position of the
;2nd table segment ...
;End of table definition
;Start position Y in segment 2 = 10
;End position Y in segment 2 = 40
;Segment 2 belongs to LV X = 30.0.
Path traversing behavior
9.3 Curve tables (CTAB)
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