G-code is the instruction set FDM printers execute: G codes handle motion/positioning, M codes handle machine state (temperature, fans, motors), T codes select the active tool. This note covers the commands emitted by Anycubic Slicer Next in a typical sliced print file.
Tool selection (T-codes)
T0, T1, … — Select tool/extruder
T0 ; select extruder 0 (the first/only extruder on single-tool printers)No other parameters. On a single-extruder printer this is emitted once near the start of the file for consistency with multi-tool firmware, which otherwise defaults to whatever tool was last active.
Motion (G-codes)
G0 — Fast (non-print) move
Same syntax as G1, but signals a travel move (no extrusion expected) so firmware can move at max speed.
G0 X12 ; move 12mm on the X axisG1 — Linear move
Move the print head (and optionally extrude) in a straight line.
G1 X127.525 Y127.525 F21000 ; move to X/Y at feedrate F (mm/min)
G1 Z0.200 ; move Z axis (layer change)
G1 E1 F3600 ; extrude/retract only, no XY movementX,Y,Z: target position (absolute or relative, seeG90/G91).E: extruder position/amount (positive extrudes, negative retracts).F: feedrate in mm/min, sticky until changed.
G2 / G3 — Arc move
Move in a clockwise (G2) or counter-clockwise (G3) arc.
G2 X105 Y30 I20.5 J20.5 ; clockwise arc to (105, 30)X/Y: end point. I/J: center offset from the current position (X/Y respectively). R: radius, as an alternative to I/J.
G4 — Dwell
G4 S5 ; pause 5 seconds, no motion
G4 P500 ; pause 500 millisecondsS: seconds, P: milliseconds. Blocks execution with no movement or extrusion — used to hold a temperature or let something settle (drip, cool, soak) before the next command. Not emitted by Anycubic Slicer Next in cube.gcode, but confirmed present in the Kobra 3’s Klipper source (registered in toolhead.py).
G10 / G11 — Firmware retract / unretract
G10 ; retract using the firmware's configured length/feedrate/z-hop
G11 ; unretract (prime back) the same amountOptional S1 marks it as a tool-change retract on multi-extruder setups, using a separate (usually longer) configured length. Not used in cube.gcode — this slicer does manual retraction instead via a plain G1 E<negative> F<feedrate> move (see G1); G10/G11 are an alternative where the retract distance/speed/z-hop live in firmware config rather than being repeated on every G1 line.
G21 — Set units to millimeters
No parameters. Declares all subsequent coordinates as millimeters (vs. G20 for inches).
G28 — Home axes
G28 ; home all axes
G28 X Y ; home only X and YOmitting axis letters homes everything.
G90 / G91 — Positioning mode
G90 ; absolute positioning for X/Y/ZG90 makes coordinates absolute; G91 makes them relative to the current position. Firmwares (Marlin/Prusa) commonly keep XYZ absolute (G90) while switching only the extruder to relative (M83).
G92 — Set position
Redefine the current position without moving, most often used to zero the extruder after a retract/prime sequence.
G92 E0 ; treat current extruder position as 0G9111 — Custom start macro (Anycubic Kobra 3 series)
A single slicer-emitted command that bundles the printer’s entire startup routine — bed/nozzle heating, bed mesh handling, homing, nozzle wipe, priming line — behind one call, customizable per printer model in Anycubic Slicer Next. Reference: G9111 Command Customization Guide.
G9111 bedTemp=60 extruderTemp=220bedTemp,extruderTemp: target temperatures (°C) substituted into the underlying macro.
On Kobra 3 / Kobra 3 Max / Kobra S1, the macro body is built from standard moves (G0, G1, G28 W for corner homing) plus Klipper machine macros not covered elsewhere in this note:
BED_MESH_CLEAR— disables the active bed mesh compensation, no parameters. A bed mesh is a grid of Z-height probe points used to correct each move’s Z on the fly for an imperfectly flat bed; clearing it before re-homing/re-leveling avoids applying a stale mesh from a previous print during the new probing pass. Stock Klipperbed_meshmodule, documented.BED_MESH_PROFILE LOAD="default"— restores a saved mesh profile by name (LOAD=/SAVE=/REMOVE=). Same stock module;SAVE=/REMOVE=additionally require aSAVE_CONFIGafterwards to persist.CLOSE_STEALTHCHOP STEPPER=<axis>/OPEN_STEALTHCHOP STEPPER=<axis>,LEVIQ2_AUTO_ZOFFSET(auto Z-offset via the LeviQ2 probe), andHOME_XY— Anycubic-specific macros with no matching module in their published Kobra3 Klipper source (klipper-mcu/klippy/extras); undocumented beyond their appearance in the wiki example.
Anycubic’s own template for that macro body writes temperatures as M140 S{first_layer_bed_temperature} I1 rather than a literal number. The {...} is slicer placeholder syntax: a variable the slicer substitutes with the actual profile value at slice time — it never reaches the printer. cube.gcode never shows this expanded form because the slicer emits the single G9111 bedTemp=60 extruderTemp=220 call instead, with 60/220 already substituted; the firmware performs the same placeholder substitution internally when it expands G9111 into that macro body. Sending an unresolved {...} placeholder straight to the printer (e.g. hand-editing a file before printing it over USB) is a hard failure, not a silent no-op — the firmware’s parser expects a number after S and aborts the line with a parse error.
Machine state (M-codes)
M73 — Set/report print progress
M73 P44 R0 QuietR0 SportR0 ; NormalR1.482sP: percent complete.R: estimated remaining time (minutes), withQuiet/Sportvariants for printers with multiple fan/speed profiles. Purely informational — used to drive the printer’s display, has no effect on motion.
M75 / M84 — Print timer / disable motors
M75 ; start the print job timer
M84 ; disable steppers (end of print)M83 — Extruder relative mode
M83 ; use relative distances for extrusionKeeps XYZ absolute (G90) while the E axis moves relative to its current value — the standard slicer convention for extrusion.
M104 / M140 — Set temperature (non-blocking)
M104 S0 ; turn off temperature (hotend)
M140 S0 ; turn off heatbedS is the target temperature in °C. Non-blocking: the printer moves on immediately without waiting to reach it (compare blocking M109/M190). Inside G9111 start macros both also appear with a trailing I1 (e.g. M140 S{first_layer_bed_temperature} I1); Anycubic’s docs don’t define it, and the Kobra 3 Klipper source shows cmd_M140 only reads S — I1 is parsed but silently ignored, effectively a no-op.
M109 — Set hotend temperature and wait
M109 S200 ; heat to 200°C and block until reachedBlocking counterpart of M104 — used inside G9111-style start macros to ensure the nozzle is fully heated before homing/wiping/priming continues. Same inert I1 parameter appears here too.
M106 / M107 — Fan control
M106 S0 ; set part-cooling fan speed (S: 0-255)
M107 ; turn fan offM117 — Set LCD message
M117 ; display a status message on the printer's screenM201 / M203 / M204 / M205 — Motion limits
M201 X20000 Y20000 Z1000 E20000 ; max acceleration per axis (mm/sec^2)
M203 X600 Y600 Z15 E600 ; max feedrate per axis (mm/sec)
M204 P20000 R20000 T20000 ; max acceleration: P=print, R=retract, T=travel
M205 X20.00 Y20.00 Z20.00 E20.00 ; jerk limits per axis (mm/sec)M204 also appears mid-print with a single axis, e.g. M204 S500, to temporarily override the print acceleration for a specific move (like the perimeter/skirt).
M400 — Wait for moves to finish
No parameters. Blocks until the motion queue is empty — used before a state change (like turning off heaters) that shouldn’t interrupt in-flight moves.
M900 — Linear advance / pressure advance
M900 K0.051 ; set pressure advance factor KK is the pressure-advance coefficient tuned for the filament/hotend combo, compensating for pressure buildup in the extruder during acceleration.
Cheatsheet
Startup sequence
M83 ; relative extrusion
G90 ; absolute XYZ
G21 ; millimeters
M900 K0.051 ; pressure advanceShutdown sequence
M400 ; wait for moves to finish
G92 E0 ; zero extruder
M140 S0 ; heatbed off
M104 S0 ; hotend off
M107 ; fan off
M84 ; disable motors