Siemens SINUMERIK 840D sl Function Manual page 527

Number of TRACYL structures
Three of the 10 permitted data structures for transformations may be assigned to the
TRACYL function. They are characterized by the fact that the value assigned with MD24100
$MC_TRAFO_TYPE_n is 512 or 513 or 514.
The following machine data must be set for a maximum of 3 of these TRACYL
transformations:
MD24800 $MC_TRACYL_ROT_AX_OFFSET_t
MD24810 $MC_TRACYL_ROT_SIGN_IS_PLUS_t
MD24820 $MC_TRACYL_BASE_TOOL_t
In this case, t specifies the number of the declared TRACYL transformation (maximum of 3).
Extended Functions
Function Manual, 09/2009, 6FC5397-1BP20-0BA0
M1: Kinematic transformation
7.3 TRACYL (option)
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