Siemens SINUMERIK 840D sl Function Manual page 597

Figure 9-8 Software cams for modulo rotary axis (plus cam - minus cam > 180 degrees)
Suppression of signal inversion
With the following setting, selection of signal inversion for
"plus cam - minus cam > 180 degrees" can be suppressed.
MD10485 SW_CAM_MODE bit 1=1
Extended Functions
Function Manual, 10/2015, 6FC5397-1BP40-5BA3
N3: Software cams, position switching cycles - only 840D sl
9.2 Cam signals and cam positions
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