Siemens SINUMERIK 840Di Function Manual page 1685

2.1.3 Calculation of the tool offset
D No.
The D no. is sufficient for calculating the tool compensations (can be set via MD).
Example:
The above compensation block is to be calculated in the NC.
Part program call:
...
D
n
2.1.4 Address extension for NC addresses T and M
MD20096
Machine data:
MD20096 $MC_T_M_ADDRESS_EXT_IS_SPINO
can be used to define whether the address extension of T and M is to be interpreted as a
spindle number even if tool management is not activated.
The same rules then apply to the reference between the D number and T number as when
the "Tool management" function is active.
Tool Compensation (W1)
Function Manual, 08/2005 Edition, 6FC5397-0BP10-0BA0
Detailed Description
2.1 Tool
2-5