Siemens SINUMERIK 840D sl Programming Manual page 291

Control behavior for reset and machine/option data
After reset, MD 20150: GCODE_RESET_VALUES [44] makes certain G codes effective
(45th G code group).
The initial state for the type of the smoothing is specified with MD 20150:
GCODE_RESET_VALUES [9] (10th G code group).
The G code group value active after Reset is determined via machine data MD 20150:
GCODE_RESET_VALUES [44]. In order to maintain compatibility with existing installations,
SPATH is set as default value.
The axial machine data MD 33100: COMPRESS_POS_TOL have an extended meaning:
They contain the tolerances for the compressor function and for rounding with G642.
Job Planning
Programming Manual, 06/2009, 6FC5398-2BP20-0BA0
Special motion commands
4.6 Settable path reference (SPATH, UPATH)
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