In Kinetic Control, we added a rotary unwind code, M999. Post processors can leverage M999 to rapidly wind up or unwind the continuous rotary axis on Pocket NC machines. This can be helpful to work around the software limits of the continuous rotary axis. On the V1 and V2 machines, the B axis is limited to -9999 to 9999 so in situations when a part program must rotate over ~25 ~27 times post processors must work around these limits (9,999 degrees is 27.775 rotations).
M999 requires a P parameter that specifies a desired angle of the continuous rotary axis. Without moving, the position of the continuous rotary axis will change to the closest multiple of 360 degrees from its current position to the specified P parameter. For example, if the current B location is 0 and we’d like to the command the machine to B1980 without needing to make the full ~5.5 rotations, we could issue the following codes:
...