M03, M04 and M5 g-code
M05 - stop spindle rotation
M03 - start rotating the spindle clockwise (M3 S2000)
M04 - Start rotation of the spindle counterclockwise (M4 S2000)
I want to note, that in engraving machines M3 - laser activation, M5 - turn off the laser and S - laser power
2023-11-18