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The P argument of the M254 code specifies which G5X work coordinate system to store the rotated offsets in. In the example above, we chose work coordinate system 9 to be used, or G59.3. The P argument can be any number between 1 and 9. G54-G59 are 1-6 and G59.1-G59.3 are 7-9 (see MachineKit’s LinuxCNC’s documentation of the G5X offsets). At the end of the machining operation, we switch back to G54, which is required if a subsequent machining operation is performed at a different A or B angle.
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