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G17: Select XY plane for arc moves
Supported from RepRapFirmware 3.3beta1.
The active plane determines how the tool path of an arc (G2 or G3) is interpreted. Each input channel (e.g. SD card, USB, DWC) remembers the current plane independently of the other channels.
G17 is supported in RRF 2.03 to RRF 3.2.2, however as no other plane selection command (G18, G19) is supported, it accepts this command, but takes no action on receiving it.