Siemens SINUMERIK 828D Programming Manual page 383

The same applies to the direction of circle rotation (G2/G3 or G3/G2).
Note
If you program an additive rotation with
reversed directions of rotation (positive/negative or negative/positive). Mirrors on the
geometry axes are converted automatically by the control into rotations and, where
appropriate, mirrors on the mirror axis specified in the machine data. This also applies to
settable zero offsets.
Mirror axis
The axis to be mirrored can be set in machine data:
MD10610 $MN_MIRROR_REF_AX = <value>
Value
0
1
2
3
Interpreting the programmed values
Machine data is used to specify how the programmed values are to be interpreted:
MD10612 $MN_MIRROR_TOGGLE = <value>
Value
0
1
Fundamentals
Programming Manual, 07/2010, 6FC5398-1BP40-0BA0
Significance
Mirroring is performed around the programmed axis (negation of values).
The reference axis is the X axis.
The reference axis is the Y axis.
The reference axis is the Z axis.
Significance
Programmed axis values are not evaluated.
Programmed axis values are evaluated:
For programmed axis values ≠ 0 the axis is mirrored if it has not yet been mirrored.
•
For a programmed axis value = 0 mirroring is deactivated.
•
Coordinate transformations (frames)
12.7 Programmable mirroring (MIRROR, AMIRROR)
after , you may have to work with
AROT MIRROR
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