g2dialect Consensus Mcodes

This page lists common Mcodes used across NIST, Fanuc, Haas, Tormach, LinuxCNC and are typically documented in the CNC Cookbook and other sources. It does not list the numerous Mcodes used in the 3D printing arena, as these are not used or may be in conflict with standard CNC machines.

See also Consensus Gcode

Consensus Mcode Usage

This table lists rough consensus usage from the above sources.

Gcode	Command	Usage / Notes
M0	Program Stop	Stop motion
M1	Optional Program Stop
M2	Program End
M3	Spindle On, Clockwise
M4	Spindle On, Counterclockwise
M5	Spindle Stop
M6	Tool Change
M7	Mist Coolant On
M8	Flood Coolant On
M9	Mist And Flood Coolant Off
M19	Orient Spindle	(Fanuc, Haas)
M30	Program End
M48	Enable Feed & Spindle Overrides
M49	Disable Feed & Spindle Overrides
M50	Feed Override Control
M51	Spindle Override Control
M60	Pallet Change Pause	(LinuxCNC)
M62	Digital Output - Turn on sync w/motion	(LinuxCNC)
M63	Digital Output - Turn off sync w/motion	(LinuxCNC)
M64	Digital Output - Turn on immediately	(LinuxCNC)
M65	Digital Output - Turn off immediately	(LinuxCNC)
M66	Wait on Input	(LinuxCNC)
M67	Analog Output Control	(LinuxCNC)
M68	Analog Output Control	(LinuxCNC)
M98	Call Macro/Subprogram
M99	Return from Macro/Subprogram

Mcodes 100 and above are user defined