Siemens SINUMERIK 840D sl Function Manual page 201

SD42692 $SC_JOG_CIRCLE_MODE, bit 0
This bit also specifies the traversing direction along the circular path.
Figure 4-6
Extended Functions
Function Manual, 10/2015, 6FC5397-1BP40-5BA3
Circular travel in JOG: Circle segment machining
H1: Manual and handwheel travel
4.11 Circular travel in JOG
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