klipper-dgus/docs/G-Codes.md

# G-Codes

This document describes the commands that Klipper supports. These are
commands that one may enter into the OctoPrint terminal tab.

## G-Code commands

Klipper supports the following standard G-Code commands:
- Move (G0 or G1): `G1 [X<pos>] [Y<pos>] [Z<pos>] [E<pos>] [F<speed>]`
- Dwell: `G4 P<milliseconds>`
- Move to origin: `G28 [X] [Y] [Z]`
- Turn off motors: `M18` or `M84`
- Wait for current moves to finish: `M400`
- Use absolute/relative distances for extrusion: `M82`, `M83`
- Use absolute/relative coordinates: `G90`, `G91`
- Set position: `G92 [X<pos>] [Y<pos>] [Z<pos>] [E<pos>]`
- Set speed factor override percentage: `M220 S<percent>`
- Set extrude factor override percentage: `M221 S<percent>`
- Set acceleration: `M204 S<value>` OR `M204 P<value> T<value>`
  - Note: If S is not specified and both P and T are specified, then
    the acceleration is set to the minimum of P and T. If only one of
    P or T is specified, the command has no effect.
- Get extruder temperature: `M105`
- Set extruder temperature: `M104 [T<index>] [S<temperature>]`
- Set extruder temperature and wait: `M109 [T<index>] S<temperature>`
  - Note: M109 always waits for temperature to settle at requested
    value
- Set bed temperature: `M140 [S<temperature>]`
- Set bed temperature and wait: `M190 S<temperature>`
  - Note: M190 always waits for temperature to settle at requested
    value
- Set fan speed: `M106 S<value>`
- Turn fan off: `M107`
- Emergency stop: `M112`
- Get current position: `M114`
- Get firmware version: `M115`

For further details on the above commands see the
[RepRap G-Code documentation](http://reprap.org/wiki/G-code).

Klipper's goal is to support the G-Code commands produced by common
3rd party software (eg, OctoPrint, Printrun, Slic3r, Cura, etc.) in
their standard configurations. It is not a goal to support every
possible G-Code command. Instead, Klipper prefers human readable
["extended G-Code commands"](#additional-commands). Similarly, the
G-Code terminal output is only intended to be human readable - see the
[API Server document](API_Server.md) if controlling Klipper from
external software.

If one requires a less common G-Code command then it may be possible
to implement it with a custom
[gcode_macro config section](Config_Reference.md#gcode_macro). For
example, one might use this to implement: `G12`, `G29`, `G30`, `G31`,
`M42`, `M80`, `M81`, `T1`, etc.

## Additional Commands

Klipper uses "extended" G-Code commands for general configuration and
status. These extended commands all follow a similar format - they
start with a command name and may be followed by one or more
parameters. For example: `SET_SERVO SERVO=myservo ANGLE=5.3`. In this
document, the commands and parameters are shown in uppercase, however
they are not case sensitive. (So, "SET_SERVO" and "set_servo" both run
the same command.)

This section is organized by Klipper module name, which generally
follows the section names specified in the
[printer configuration file](Config_Reference.md). Note that some
modules are automatically loaded.

### [adxl345]

The following commands are available when an
[adxl345 config section](Config_Reference.md#adxl345) is enabled.

#### ACCELEROMETER_MEASURE
`ACCELEROMETER_MEASURE [CHIP=<config_name>] [NAME=<value>]`: Starts
accelerometer measurements at the requested number of samples per
second. If CHIP is not specified it defaults to "adxl345". The command
works in a start-stop mode: when executed for the first time, it
starts the measurements, next execution stops them. The results of
measurements are written to a file named
`/tmp/adxl345-<chip>-<name>.csv` where `<chip>` is the name of the
accelerometer chip (`my_chip_name` from `[adxl345 my_chip_name]`) and
`<name>` is the optional NAME parameter. If NAME is not specified it
defaults to the current time in "YYYYMMDD_HHMMSS" format. If the
accelerometer does not have a name in its config section (simply
`[adxl345]`) then `<chip>` part of the name is not generated.

#### ACCELEROMETER_QUERY
`ACCELEROMETER_QUERY [CHIP=<config_name>] [RATE=<value>]`: queries
accelerometer for the current value. If CHIP is not specified it
defaults to "adxl345". If RATE is not specified, the default value is
used. This command is useful to test the connection to the ADXL345
accelerometer: one of the returned values should be a free-fall
acceleration (+/- some noise of the chip).

#### ACCELEROMETER_DEBUG_READ
`ACCELEROMETER_DEBUG_READ [CHIP=<config_name>] REG=<register>`:
queries ADXL345 register "register" (e.g. 44 or 0x2C). Can be useful
for debugging purposes.

#### ACCELEROMETER_DEBUG_WRITE
`ACCELEROMETER_DEBUG_WRITE [CHIP=<config_name>] REG=<register>
VAL=<value>`: Writes raw "value" into a register "register". Both
"value" and "register" can be a decimal or a hexadecimal integer. Use
with care, and refer to ADXL345 data sheet for the reference.

### [angle]

The following commands are available when an
[angle config section](Config_Reference.md#angle) is enabled.

#### ANGLE_CALIBRATE
`ANGLE_CALIBRATE CHIP=<chip_name>`: Perform angle calibration on the
given sensor (there must be an `[angle chip_name]` config section that
has specified a `stepper` parameter). IMPORTANT - this tool will
command the stepper motor to move without checking the normal
kinematic boundary limits. Ideally the motor should be disconnected
from any printer carriage before performing calibration. If the
stepper can not be disconnected from the printer, make sure the
carriage is near the center of its rail before starting calibration.
(The stepper motor may move forwards or backwards two full rotations
during this test.) After completing this test use the `SAVE_CONFIG`
command to save the calibration data to the config file. In order to
use this tool the Python "numpy" package must be installed (see the
[measuring resonance document](Measuring_Resonances.md#software-installation)
for more information).

#### ANGLE_DEBUG_READ
`ANGLE_DEBUG_READ CHIP=<config_name> REG=<register>`: Queries sensor
register "register" (e.g. 44 or 0x2C). Can be useful for debugging
purposes. This is only available for tle5012b chips.

#### ANGLE_DEBUG_WRITE
`ANGLE_DEBUG_WRITE CHIP=<config_name> REG=<register> VAL=<value>`:
Writes raw "value" into register "register". Both "value" and
"register" can be a decimal or a hexadecimal integer. Use with care,
and refer to sensor data sheet for the reference. This is only
available for tle5012b chips.

### [bed_mesh]

The following commands are available when the
[bed_mesh config section](Config_Reference.md#bed_mesh) is enabled
(also see the [bed mesh guide](Bed_Mesh.md)).

#### BED_MESH_CALIBRATE
`BED_MESH_CALIBRATE [METHOD=manual] [<probe_parameter>=<value>]
[<mesh_parameter>=<value>]`: This command probes the bed using
generated points specified by the parameters in the config. After
probing, a mesh is generated and z-movement is adjusted according to
the mesh. See the PROBE command for details on the optional probe
parameters. If METHOD=manual is specified then the manual probing tool
is activated - see the MANUAL_PROBE command above for details on the
additional commands available while this tool is active.

#### BED_MESH_OUTPUT
`BED_MESH_OUTPUT PGP=[<0:1>]`: This command outputs the current probed
z values and current mesh values to the terminal.  If PGP=1 is
specified the X, Y coordinates generated by bed_mesh, along with their
associated indices, will be output to the terminal.

#### BED_MESH_MAP
`BED_MESH_MAP`: Like to BED_MESH_OUTPUT, this command prints the
current state of the mesh to the terminal.  Instead of printing the
values in a human readable format, the state is serialized in json
format. This allows octoprint plugins to easily capture the data and
generate height maps approximating the bed's surface.

#### BED_MESH_CLEAR
`BED_MESH_CLEAR`: This command clears the mesh and removes all z
adjustment.  It is recommended to put this in your end-gcode.

#### BED_MESH_PROFILE
`BED_MESH_PROFILE LOAD=<name> SAVE=<name> REMOVE=<name>`: This command
provides profile management for mesh state. LOAD will restore the mesh
state from the profile matching the supplied name. SAVE will save the
current mesh state to a profile matching the supplied name. Remove
will delete the profile matching the supplied name from persistent
memory. Note that after SAVE or REMOVE operations have been run the
SAVE_CONFIG gcode must be run to make the changes to persistent memory
permanent.

#### BED_MESH_OFFSET
`BED_MESH_OFFSET [X=<value>] [Y=<value>]`: Applies X and/or Y offsets
to the mesh lookup. This is useful for printers with independent
extruders, as an offset is necessary to produce correct Z adjustment
after a tool change.

### [bed_screws]

The following commands are available when the
[bed_screws config section](Config_Reference.md#bed_screws) is enabled
(also see the
[manual level guide](Manual_Level.md#adjusting-bed-leveling-screws)).

#### BED_SCREWS_ADJUST
`BED_SCREWS_ADJUST`: This command will invoke the bed screws
adjustment tool. It will command the nozzle to different locations (as
defined in the config file) and allow one to make adjustments to the
bed screws so that the bed is a constant distance from the nozzle.

### [bed_tilt]

The following commands are available when the
[bed_tilt config section](Config_Reference.md#bed_tilt) is enabled.

#### BED_TILT_CALIBRATE
`BED_TILT_CALIBRATE [METHOD=manual] [<probe_parameter>=<value>]`: This
command will probe the points specified in the config and then
recommend updated x and y tilt adjustments. See the PROBE command for
details on the optional probe parameters. If METHOD=manual is
specified then the manual probing tool is activated - see the
MANUAL_PROBE command above for details on the additional commands
available while this tool is active.

### [bltouch]

The following command is available when a
[bltouch config section](Config_Reference.md#bltouch) is enabled (also
see the [BL-Touch guide](BLTouch.md)).

#### BLTOUCH_DEBUG
`BLTOUCH_DEBUG COMMAND=<command>`: This sends a command to the
BLTouch. It may be useful for debugging. Available commands are:
`pin_down`, `touch_mode`, `pin_up`, `self_test`, `reset`. A BL-Touch
V3.0 or V3.1 may also support `set_5V_output_mode`,
`set_OD_output_mode`, `output_mode_store` commands.

#### BLTOUCH_STORE
`BLTOUCH_STORE MODE=<output_mode>`: This stores an output mode in the
EEPROM of a BLTouch V3.1 Available output_modes are: `5V`, `OD`

### [configfile]

The configfile module is automatically loaded.

#### SAVE_CONFIG
`SAVE_CONFIG`: This command will overwrite the main printer config
file and restart the host software. This command is used in
conjunction with other calibration commands to store the results of
calibration tests.

### [delayed_gcode]

The following command is enabled if a
[delayed_gcode config section](Config_Reference.md#delayed_gcode) has
been enabled (also see the
[template guide](Command_Templates.md#delayed-gcodes)).

#### UPDATE_DELAYED_GCODE
`UPDATE_DELAYED_GCODE [ID=<name>] [DURATION=<seconds>]`: Updates the
delay duration for the identified [delayed_gcode] and starts the timer
for gcode execution. A value of 0 will cancel a pending delayed gcode
from executing.

### [delta_calibrate]

The following commands are available when the
[delta_calibrate config section](Config_Reference.md#linear-delta-kinematics)
is enabled (also see the [delta calibrate guide](Delta_Calibrate.md)).

#### DELTA_CALIBRATE
`DELTA_CALIBRATE [METHOD=manual] [<probe_parameter>=<value>]`: This
command will probe seven points on the bed and recommend updated
endstop positions, tower angles, and radius. See the PROBE command for
details on the optional probe parameters. If METHOD=manual is
specified then the manual probing tool is activated - see the
MANUAL_PROBE command above for details on the additional commands
available while this tool is active.

#### DELTA_ANALYZE
`DELTA_ANALYZE`: This command is used during enhanced delta
calibration. See [Delta Calibrate](Delta_Calibrate.md) for details.

### [display]

The following command is available when a
[display config section](Config_Reference.md#gcode_macro) is enabled.

#### SET_DISPLAY_GROUP
`SET_DISPLAY_GROUP [DISPLAY=<display>] GROUP=<group>`: Set the active
display group of an lcd display. This allows to define multiple
display data groups in the config, e.g. `[display_data <group>
<elementname>]` and switch between them using this extended gcode
command. If DISPLAY is not specified it defaults to "display" (the
primary display).

### [display_status]

The display_status module is automatically loaded if a
[display config section](Config_Reference.md#display) is enabled. It
provides the following standard G-Code commands:
- Display Message: `M117 <message>`
- Set build percentage: `M73 P<percent>`

### [dual_carriage]

The following command is available when the
[dual_carriage config section](Config_Reference.md#dual_carriage) is
enabled.

#### SET_DUAL_CARRIAGE
`SET_DUAL_CARRIAGE CARRIAGE=[0|1]`: This command will set the active
carriage. It is typically invoked from the activate_gcode and
deactivate_gcode fields in a multiple extruder configuration.

### [endstop_phase]

The following commands are available when an
[endstop_phase config section](Config_Reference.md#endstop_phase) is
enabled (also see the [endstop phase guide](Endstop_Phase.md)).

#### ENDSTOP_PHASE_CALIBRATE
`ENDSTOP_PHASE_CALIBRATE [STEPPER=<config_name>]`: If no STEPPER
parameter is provided then this command will reports statistics on
endstop stepper phases during past homing operations. When a STEPPER
parameter is provided it arranges for the given endstop phase setting
to be written to the config file (in conjunction with the SAVE_CONFIG
command).

### [extruder]

The following commands are available if an
[extruder config section](Config_Reference.md#extruder) is enabled:

#### ACTIVATE_EXTRUDER
`ACTIVATE_EXTRUDER EXTRUDER=<config_name>`: In a printer with multiple
[extruder](Config_Reference.md#extruder) config sections, this command
changes the active hotend.

#### SET_PRESSURE_ADVANCE
`SET_PRESSURE_ADVANCE [EXTRUDER=<config_name>]
[ADVANCE=<pressure_advance>]
[SMOOTH_TIME=<pressure_advance_smooth_time>]`: Set pressure advance
parameters of an extruder stepper (as defined in an
[extruder](Config_Reference.md#extruder) or
[extruder_stepper](Config_Reference.md#extruder_stepper) config section).
If EXTRUDER is not specified, it defaults to the stepper defined in
the active hotend.

#### SET_EXTRUDER_ROTATION_DISTANCE
`SET_EXTRUDER_ROTATION_DISTANCE EXTRUDER=<config_name>
[DISTANCE=<distance>]`: Set a new value for the provided extruder
stepper's "rotation distance" (as defined in an
[extruder](Config_Reference.md#extruder) or
[extruder_stepper](Config_Reference.md#extruder_stepper) config section).
If the rotation distance is a negative number then the stepper motion
will be inverted (relative to the stepper direction specified in the
config file). Changed settings are not retained on Klipper reset. Use
with caution as small changes can result in excessive pressure between
extruder and hotend. Do proper calibration with filament before use.
If 'DISTANCE' value is not provided then this command will return the
current rotation distance.

#### SYNC_EXTRUDER_MOTION
`SYNC_EXTRUDER_MOTION EXTRUDER=<name> MOTION_QUEUE=<name>`: This
command will cause the stepper specified by EXTRUDER (as defined in an
[extruder](Config_Reference.md#extruder) or
[extruder_stepper](Config_Reference.md#extruder_stepper) config section)
to become synchronized to the movement of an extruder specified by
MOTION_QUEUE (as defined in an [extruder](Config_Reference.md#extruder)
config section). If MOTION_QUEUE is an empty string then the stepper
will be desynchronized from all extruder movement.

#### SET_EXTRUDER_STEP_DISTANCE
This command is deprecated and will be removed in the near future.

#### SYNC_STEPPER_TO_EXTRUDER
This command is deprecated and will be removed in the near future.

### [fan_generic]

The following command is available when a
[fan_generic config section](Config_Reference.md#fan_generic) is
enabled.

#### SET_FAN_SPEED
`SET_FAN_SPEED FAN=config_name SPEED=<speed>` This command sets the
speed of a fan. "speed" must be between 0.0 and 1.0.

### [filament_switch_sensor]

The following command is available when a
[filament_switch_sensor](Config_Reference.md#filament_switch_sensor)
or
[filament_motion_sensor](Config_Reference.md#filament_motion_sensor)
config section is enabled.

#### QUERY_FILAMENT_SENSOR
`QUERY_FILAMENT_SENSOR SENSOR=<sensor_name>`: Queries the current
status of the filament sensor. The data displayed on the terminal will
depend on the sensor type defined in the configuration.

#### SET_FILAMENT_SENSOR
`SET_FILAMENT_SENSOR SENSOR=<sensor_name> ENABLE=[0|1]`: Sets the
filament sensor on/off. If ENABLE is set to 0, the filament sensor
will be disabled, if set to 1 it is enabled.

### [firmware_retraction]

The following standard G-Code commands are available when the
[firmware_retraction config section](Config_Reference.md#firmware_retraction)
is enabled. These commands allow you to utilize the firmware
retraction feature available in many slicers, to reduce stringing
during non-extrusion moves from one part of the print to another.
Appropriately configuring pressure advance reduces the length of
retraction required.
- `G10`: Retracts the extruder using the currently configured
  parameters.
- `G11`: Unretracts the extruder using the currently configured
  parameters.

The following additional commands are also available.

#### SET_RETRACTION
`SET_RETRACTION [RETRACT_LENGTH=<mm>] [RETRACT_SPEED=<mm/s>]
[UNRETRACT_EXTRA_LENGTH=<mm>] [UNRETRACT_SPEED=<mm/s>]`: Adjust the
parameters used by firmware retraction. RETRACT_LENGTH determines the
length of filament to retract and unretract. The speed of retraction
is adjusted via RETRACT_SPEED, and is typically set relatively
high. The speed of unretraction is adjusted via UNRETRACT_SPEED, and
is not particularly critical, although often lower than RETRACT_SPEED.
In some cases it is useful to add a small amount of additional length
on unretraction, and this is set via UNRETRACT_EXTRA_LENGTH.
SET_RETRACTION is commonly set as part of slicer per-filament
configuration, as different filaments require different parameter
settings.

#### GET_RETRACTION
`GET_RETRACTION`: Queries the current parameters used by firmware
retraction and displays them on the terminal.

### [force_move]

The force_move module is automatically loaded, however some commands
require setting `enable_force_move` in the
[printer config](Config_Reference.md#force_move).

#### STEPPER_BUZZ
`STEPPER_BUZZ STEPPER=<config_name>`: Move the given stepper forward
one mm and then backward one mm, repeated 10 times. This is a
diagnostic tool to help verify stepper connectivity.

#### FORCE_MOVE
`FORCE_MOVE STEPPER=<config_name> DISTANCE=<value> VELOCITY=<value>
[ACCEL=<value>]`: This command will forcibly move the given stepper
the given distance (in mm) at the given constant velocity (in mm/s).
If ACCEL is specified and is greater than zero, then the given
acceleration (in mm/s^2) will be used; otherwise no acceleration is
performed. No boundary checks are performed; no kinematic updates are
made; other parallel steppers on an axis will not be moved. Use
caution as an incorrect command could cause damage! Using this command
will almost certainly place the low-level kinematics in an incorrect
state; issue a G28 afterwards to reset the kinematics. This command is
intended for low-level diagnostics and debugging.

#### SET_KINEMATIC_POSITION
`SET_KINEMATIC_POSITION [X=<value>] [Y=<value>] [Z=<value>]`: Force
the low-level kinematic code to believe the toolhead is at the given
cartesian position. This is a diagnostic and debugging command; use
SET_GCODE_OFFSET and/or G92 for regular axis transformations. If an
axis is not specified then it will default to the position that the
head was last commanded to. Setting an incorrect or invalid position
may lead to internal software errors. This command may invalidate
future boundary checks; issue a G28 afterwards to reset the
kinematics.

### [gcode]

The gcode module is automatically loaded.

#### RESTART
`RESTART`: This will cause the host software to reload its config and
perform an internal reset. This command will not clear error state
from the micro-controller (see FIRMWARE_RESTART) nor will it load new
software (see
[the FAQ](FAQ.md#how-do-i-upgrade-to-the-latest-software)).

#### FIRMWARE_RESTART
`FIRMWARE_RESTART`: This is similar to a RESTART command, but it also
clears any error state from the micro-controller.

#### STATUS
`STATUS`: Report the Klipper host software status.

#### HELP
`HELP`: Report the list of available extended G-Code commands.

### [gcode_arcs]

The following standard G-Code commands are available if a
[gcode_arcs config section](Config_Reference.md#gcode_arcs) is
enabled:
- Controlled Arc Move (G2 or G3): `G2 [X<pos>] [Y<pos>] [Z<pos>]
  [E<pos>] [F<speed>] I<value> J<value>`

### [gcode_macro]

The following command is available when a
[gcode_macro config section](Config_Reference.md#gcode_macro) is
enabled (also see the
[command templates guide](Command_Templates.md)).

#### SET_GCODE_VARIABLE
`SET_GCODE_VARIABLE MACRO=<macro_name> VARIABLE=<name> VALUE=<value>`:
This command allows one to change the value of a gcode_macro variable
at run-time. The provided VALUE is parsed as a Python literal.

### [gcode_move]

The gcode_move module is automatically loaded.

#### GET_POSITION
`GET_POSITION`: Return information on the current location of the
toolhead. See the developer documentation of
[GET_POSITION output](Code_Overview.md#coordinate-systems) for more
information.

#### SET_GCODE_OFFSET
`SET_GCODE_OFFSET [X=<pos>|X_ADJUST=<adjust>]
[Y=<pos>|Y_ADJUST=<adjust>] [Z=<pos>|Z_ADJUST=<adjust>] [MOVE=1
[MOVE_SPEED=<speed>]]`: Set a positional offset to apply to future
G-Code commands. This is commonly used to virtually change the Z bed
offset or to set nozzle XY offsets when switching extruders. For
example, if "SET_GCODE_OFFSET Z=0.2" is sent, then future G-Code moves
will have 0.2mm added to their Z height. If the X_ADJUST style
parameters are used, then the adjustment will be added to any existing
offset (eg, "SET_GCODE_OFFSET Z=-0.2" followed by "SET_GCODE_OFFSET
Z_ADJUST=0.3" would result in a total Z offset of 0.1). If "MOVE=1" is
specified then a toolhead move will be issued to apply the given
offset (otherwise the offset will take effect on the next absolute
G-Code move that specifies the given axis). If "MOVE_SPEED" is
specified then the toolhead move will be performed with the given
speed (in mm/s); otherwise the toolhead move will use the last
specified G-Code speed.

#### SAVE_GCODE_STATE
`SAVE_GCODE_STATE [NAME=<state_name>]`: Save the current g-code
coordinate parsing state. Saving and restoring the g-code state is
useful in scripts and macros. This command saves the current g-code
absolute coordinate mode (G90/G91), absolute extrude mode (M82/M83),
origin (G92), offset (SET_GCODE_OFFSET), speed override (M220),
extruder override (M221), move speed, current XYZ position, and
relative extruder "E" position. If NAME is provided it allows one to
name the saved state to the given string. If NAME is not provided it
defaults to "default".

#### RESTORE_GCODE_STATE
`RESTORE_GCODE_STATE [NAME=<state_name>] [MOVE=1
[MOVE_SPEED=<speed>]]`: Restore a state previously saved via
SAVE_GCODE_STATE. If "MOVE=1" is specified then a toolhead move will
be issued to move back to the previous XYZ position. If "MOVE_SPEED"
is specified then the toolhead move will be performed with the given
speed (in mm/s); otherwise the toolhead move will use the restored
g-code speed.

### [hall_filament_width_sensor]

The following commands are available when the
[tsl1401cl filament width sensor config section](Config_Reference.md#tsl1401cl_filament_width_sensor)
or [hall filament width sensor config section](Config_Reference.md#hall_filament_width_sensor)
is enabled (also see [TSLl401CL Filament Width Sensor](TSL1401CL_Filament_Width_Sensor.md)
and [Hall Filament Width Sensor](Hall_Filament_Width_Sensor.md)):

#### QUERY_FILAMENT_WIDTH
`QUERY_FILAMENT_WIDTH`: Return the current measured filament width.

#### RESET_FILAMENT_WIDTH_SENSOR
`RESET_FILAMENT_WIDTH_SENSOR`: Clear all sensor readings. Helpful
after filament change.

#### DISABLE_FILAMENT_WIDTH_SENSOR
`DISABLE_FILAMENT_WIDTH_SENSOR`: Turn off the filament width sensor
and stop using it for flow control.

#### ENABLE_FILAMENT_WIDTH_SENSOR
`ENABLE_FILAMENT_WIDTH_SENSOR`: Turn on the filament width sensor and
start using it for flow control.

#### QUERY_RAW_FILAMENT_WIDTH
`QUERY_RAW_FILAMENT_WIDTH`: Return the current ADC channel readings
and RAW sensor value for calibration points.

#### ENABLE_FILAMENT_WIDTH_LOG
`ENABLE_FILAMENT_WIDTH_LOG`: Turn on diameter logging.

#### DISABLE_FILAMENT_WIDTH_LOG
`DISABLE_FILAMENT_WIDTH_LOG`: Turn off diameter logging.

### [heaters]

The heaters module is automatically loaded if a heater is defined in
the config file.

#### TURN_OFF_HEATERS
`TURN_OFF_HEATERS`: Turn off all heaters.

#### TEMPERATURE_WAIT
`TEMPERATURE_WAIT SENSOR=<config_name> [MINIMUM=<target>]
[MAXIMUM=<target>]`: Wait until the given temperature sensor is at or
above the supplied MINIMUM and/or at or below the supplied MAXIMUM.

#### SET_HEATER_TEMPERATURE
`SET_HEATER_TEMPERATURE HEATER=<heater_name>
[TARGET=<target_temperature>]`: Sets the target temperature for a
heater. If a target temperature is not supplied, the target is 0.

### [idle_timeout]

The idle_timeout module is automatically loaded.

#### SET_IDLE_TIMEOUT
`SET_IDLE_TIMEOUT [TIMEOUT=<timeout>]`: Allows the user to set the
idle timeout (in seconds).

### [input_shaper]

The following command is enabled if an
[input_shaper config section](Config_Reference.md#input_shaper) has
been enabled (also see the
[resonance compensation guide](Resonance_Compensation.md)).

#### SET_INPUT_SHAPER
`SET_INPUT_SHAPER [SHAPER_FREQ_X=<shaper_freq_x>]
[SHAPER_FREQ_Y=<shaper_freq_y>] [DAMPING_RATIO_X=<damping_ratio_x>]
[DAMPING_RATIO_Y=<damping_ratio_y>] [SHAPER_TYPE=<shaper>]
[SHAPER_TYPE_X=<shaper_type_x>] [SHAPER_TYPE_Y=<shaper_type_y>]`:
Modify input shaper parameters. Note that SHAPER_TYPE parameter resets
input shaper for both X and Y axes even if different shaper types have
been configured in [input_shaper] section. SHAPER_TYPE cannot be used
together with either of SHAPER_TYPE_X and SHAPER_TYPE_Y parameters.
See [config reference](Config_Reference.md#input_shaper) for more
details on each of these parameters.

### [manual_probe]

The manual_probe module is automatically loaded.

#### MANUAL_PROBE
`MANUAL_PROBE [SPEED=<speed>]`: Run a helper script useful for
measuring the height of the nozzle at a given location. If SPEED is
specified, it sets the speed of TESTZ commands (the default is
5mm/s). During a manual probe, the following additional commands are
available:
- `ACCEPT`: This command accepts the current Z position and concludes
  the manual probing tool.
- `ABORT`: This command terminates the manual probing tool.
- `TESTZ Z=<value>`: This command moves the nozzle up or down by the
  amount specified in "value". For example, `TESTZ Z=-.1` would move
  the nozzle down .1mm while `TESTZ Z=.1` would move the nozzle up
  .1mm. The value may also be `+`, `-`, `++`, or `--` to move the
  nozzle up or down an amount relative to previous attempts.

#### Z_ENDSTOP_CALIBRATE
`Z_ENDSTOP_CALIBRATE [SPEED=<speed>]`: Run a helper script useful for
calibrating a Z position_endstop config setting. See the MANUAL_PROBE
command for details on the parameters and the additional commands
available while the tool is active.

#### Z_OFFSET_APPLY_ENDSTOP
`Z_OFFSET_APPLY_ENDSTOP`: Take the current Z Gcode offset (aka,
babystepping), and subtract it from the stepper_z endstop_position.
This acts to take a frequently used babystepping value, and "make it
permanent". Requires a `SAVE_CONFIG` to take effect.

### [manual_stepper]

The following command is available when a
[manual_stepper config section](Config_Reference.md#manual_stepper) is
enabled.

#### MANUAL_STEPPER
`MANUAL_STEPPER STEPPER=config_name [ENABLE=[0|1]]
[SET_POSITION=<pos>] [SPEED=<speed>] [ACCEL=<accel>] [MOVE=<pos>
[STOP_ON_ENDSTOP=[1|2|-1|-2]] [SYNC=0]]`: This command will alter the
state of the stepper. Use the ENABLE parameter to enable/disable the
stepper. Use the SET_POSITION parameter to force the stepper to think
it is at the given position. Use the MOVE parameter to request a
movement to the given position. If SPEED and/or ACCEL is specified
then the given values will be used instead of the defaults specified
in the config file. If an ACCEL of zero is specified then no
acceleration will be performed. If STOP_ON_ENDSTOP=1 is specified then
the move will end early should the endstop report as triggered (use
STOP_ON_ENDSTOP=2 to complete the move without error even if the
endstop does not trigger, use -1 or -2 to stop when the endstop
reports not triggered). Normally future G-Code commands will be
scheduled to run after the stepper move completes, however if a manual
stepper move uses SYNC=0 then future G-Code movement commands may run
in parallel with the stepper movement.

### [led]

The following command is available when any of the
[led config sections](Config_Reference.md#leds) are enabled.

#### SET_LED
`SET_LED LED=<config_name> RED=<value> GREEN=<value> BLUE=<value>
WHITE=<value> [INDEX=<index>] [TRANSMIT=0] [SYNC=1]`: This sets the
LED output. Each color `<value>` must be between 0.0 and 1.0. The
WHITE option is only valid on RGBW LEDs. If the LED supports multiple
chips in a daisy-chain then one may specify INDEX to alter the color
of just the given chip (1 for the first chip, 2 for the second,
etc.). If INDEX is not provided then all LEDs in the daisy-chain will
be set to the provided color. If TRANSMIT=0 is specified then the
color change will only be made on the next SET_LED command that does
not specify TRANSMIT=0; this may be useful in combination with the
INDEX parameter to batch multiple updates in a daisy-chain. By
default, the SET_LED command will sync it's changes with other ongoing
gcode commands.  This can lead to undesirable behavior if LEDs are
being set while the printer is not printing as it will reset the idle
timeout. If careful timing is not needed, the optional SYNC=0
parameter can be specified to apply the changes without resetting the
idle timeout.

#### SET_LED_TEMPLATE
`SET_LED_TEMPLATE LED=<led_name> TEMPLATE=<template_name>
[<param_x>=<literal>] [INDEX=<index>]`: Assign a
[display_template](Config_Reference.md#display_template) to a given
[LED](Config_Reference.md#leds). For example, if one defined a
`[display_template my_led_template]` config section then one could
assign `TEMPLATE=my_led_template` here. The display_template should
produce a comma separated string containing four floating point
numbers corresponding to red, green, blue, and white color settings.
The template will be continuously evaluated and the LED will be
automatically set to the resulting colors. One may set
display_template parameters to use during template evaluation
(parameters will be parsed as Python literals). If INDEX is not
specified then all chips in the LED's daisy-chain will be set to the
template, otherwise only the chip with the given index will be
updated. If TEMPLATE is an empty string then this command will clear
any previous template assigned to the LED (one can then use `SET_LED`
commands to manage the LED's color settings).

### [output_pin]

The following command is available when an
[output_pin config section](Config_Reference.md#output_pin) is
enabled.

#### SET_PIN
`SET_PIN PIN=config_name VALUE=<value> CYCLE_TIME=<cycle_time>`:
Note - hardware PWM does not currently support the CYCLE_TIME
parameter and will use the cycle time defined in the config.

### [palette2]

The following commands are available when the
[palette2 config section](Config_Reference.md#palette2) is enabled.

Palette prints work by embedding special OCodes (Omega Codes) in the
GCode file:
- `O1`...`O32`: These codes are read from the GCode stream and processed
  by this module and passed to the Palette 2 device.

The following additional commands are also available.

#### PALETTE_CONNECT
`PALETTE_CONNECT`: This command initializes the connection with the
Palette 2.

#### PALETTE_DISCONNECT
`PALETTE_DISCONNECT`: This command disconnects from the Palette 2.

#### PALETTE_CLEAR
`PALETTE_CLEAR`: This command instructs the Palette 2 to clear all of
the input and output paths of filament.

#### PALETTE_CUT
`PALETTE_CUT`: This command instructs the Palette 2 to cut the
filament currently loaded in the splice core.

#### PALETTE_SMART_LOAD
`PALETTE_SMART_LOAD`: This command start the smart load sequence on
the Palette 2. Filament is loaded automatically by extruding it the
distance calibrated on the device for the printer, and instructs the
Palette 2 once the loading has been completed. This command is the
same as pressing **Smart Load** directly on the Palette 2 screen after
the filament load is complete.

### [pid_calibrate]

The pid_calibrate module is automatically loaded if a heater is defined
in the config file.

#### PID_CALIBRATE
`PID_CALIBRATE HEATER=<config_name> TARGET=<temperature>
[WRITE_FILE=1]`: Perform a PID calibration test. The specified heater
will be enabled until the specified target temperature is reached, and
then the heater will be turned off and on for several cycles. If the
WRITE_FILE parameter is enabled, then the file /tmp/heattest.txt will
be created with a log of all temperature samples taken during the
test.

### [pause_resume]

The following commands are available when the
[pause_resume config section](Config_Reference.md#pause_resume) is
enabled:

#### PAUSE
`PAUSE`: Pauses the current print. The current position is captured
for restoration upon resume.

#### RESUME
`RESUME [VELOCITY=<value>]`: Resumes the print from a pause, first
restoring the previously captured position. The VELOCITY parameter
determines the speed at which the tool should return to the original
captured position.

#### CLEAR_PAUSE
`CLEAR_PAUSE`: Clears the current paused state without resuming the
print. This is useful if one decides to cancel a print after a
PAUSE. It is recommended to add this to your start gcode to make sure
the paused state is fresh for each print.

#### CANCEL_PRINT
`CANCEL_PRINT`: Cancels the current print.

### [probe]

The following commands are available when a
[probe config section](Config_Reference.md#probe) or
[bltouch config section](Config_Reference.md#bltouch) is enabled (also
see the [probe calibrate guide](Probe_Calibrate.md)).

#### PROBE
`PROBE [PROBE_SPEED=<mm/s>] [LIFT_SPEED=<mm/s>] [SAMPLES=<count>]
[SAMPLE_RETRACT_DIST=<mm>] [SAMPLES_TOLERANCE=<mm>]
[SAMPLES_TOLERANCE_RETRIES=<count>] [SAMPLES_RESULT=median|average]`:
Move the nozzle downwards until the probe triggers. If any of the
optional parameters are provided they override their equivalent
setting in the [probe config section](Config_Reference.md#probe).

#### QUERY_PROBE
`QUERY_PROBE`: Report the current status of the probe ("triggered" or
"open").

#### PROBE_ACCURACY
`PROBE_ACCURACY [PROBE_SPEED=<mm/s>] [SAMPLES=<count>]
[SAMPLE_RETRACT_DIST=<mm>]`: Calculate the maximum, minimum, average,
median, and standard deviation of multiple probe samples. By default,
10 SAMPLES are taken. Otherwise the optional parameters default to
their equivalent setting in the probe config section.

#### PROBE_CALIBRATE
`PROBE_CALIBRATE [SPEED=<speed>] [<probe_parameter>=<value>]`: Run a
helper script useful for calibrating the probe's z_offset. See the
PROBE command for details on the optional probe parameters. See the
MANUAL_PROBE command for details on the SPEED parameter and the
additional commands available while the tool is active. Please note,
the PROBE_CALIBRATE command uses the speed variable to move in XY
direction as well as Z.

#### Z_OFFSET_APPLY_PROBE
`Z_OFFSET_APPLY_PROBE`: Take the current Z Gcode offset (aka,
babystepping), and subtract if from the probe's z_offset.  This acts
to take a frequently used babystepping value, and "make it permanent".
Requires a `SAVE_CONFIG` to take effect.

### [query_adc]

The query_adc module is automatically loaded.

#### QUERY_ADC
`QUERY_ADC [NAME=<config_name>] [PULLUP=<value>]`: Report the last
analog value received for a configured analog pin. If NAME is not
provided, the list of available adc names are reported. If PULLUP is
provided (as a value in Ohms), the raw analog value along with the
equivalent resistance given that pullup is reported.

### [query_endstops]

The query_endstops module is automatically loaded. The following
standard G-Code commands are currently available, but using them is
not recommended:
- Get Endstop Status: `M119` (Use QUERY_ENDSTOPS instead.)

#### QUERY_ENDSTOPS
`QUERY_ENDSTOPS`: Probe the axis endstops and report if they are
"triggered" or in an "open" state. This command is typically used to
verify that an endstop is working correctly.

### [resonance_tester]

The following commands are available when a
[resonance_tester config section](Config_Reference.md#resonance_tester)
is enabled (also see the
[measuring resonances guide](Measuring_Resonances.md)).

#### MEASURE_AXES_NOISE
`MEASURE_AXES_NOISE`: Measures and outputs the noise for all axes of
all enabled accelerometer chips.

#### TEST_RESONANCES
`TEST_RESONANCES AXIS=<axis> OUTPUT=<resonances,raw_data>
[NAME=<name>] [FREQ_START=<min_freq>] [FREQ_END=<max_freq>]
[HZ_PER_SEC=<hz_per_sec>] [INPUT_SHAPING=[<0:1>]]`: Runs the resonance
test in all configured probe points for the requested "axis" and
measures the acceleration using the accelerometer chips configured for
the respective axis. "axis" can either be X or Y, or specify an
arbitrary direction as `AXIS=dx,dy`, where dx and dy are floating
point numbers defining a direction vector (e.g. `AXIS=X`, `AXIS=Y`, or
`AXIS=1,-1` to define a diagonal direction). Note that `AXIS=dx,dy`
and `AXIS=-dx,-dy` is equivalent. If `INPUT_SHAPING=0` or not set
(default), disables input shaping for the resonance testing, because
it is not valid to run the resonance testing with the input shaper
enabled. `OUTPUT` parameter is a comma-separated list of which outputs
will be written. If `raw_data` is requested, then the raw
accelerometer data is written into a file or a series of files
`/tmp/raw_data_<axis>_[<point>_]<name>.csv` with (`<point>_` part of
the name generated only if more than 1 probe point is configured).  If
`resonances` is specified, the frequency response is calculated
(across all probe points) and written into
`/tmp/resonances_<axis>_<name>.csv` file. If unset, OUTPUT defaults to
`resonances`, and NAME defaults to the current time in
"YYYYMMDD_HHMMSS" format.

#### SHAPER_CALIBRATE
`SHAPER_CALIBRATE [AXIS=<axis>] [NAME=<name>] [FREQ_START=<min_freq>]
[FREQ_END=<max_freq>] [HZ_PER_SEC=<hz_per_sec>]
[MAX_SMOOTHING=<max_smoothing>]`: Similarly to `TEST_RESONANCES`, runs
the resonance test as configured, and tries to find the optimal
parameters for the input shaper for the requested axis (or both X and
Y axes if `AXIS` parameter is unset). If `MAX_SMOOTHING` is unset, its
value is taken from `[resonance_tester]` section, with the default
being unset. See the
[Max smoothing](Measuring_Resonances.md#max-smoothing) of the
measuring resonances guide for more information on the use of this
feature. The results of the tuning are printed to the console, and the
frequency responses and the different input shapers values are written
to a CSV file(s) `/tmp/calibration_data_<axis>_<name>.csv`. Unless
specified, NAME defaults to the current time in "YYYYMMDD_HHMMSS"
format. Note that the suggested input shaper parameters can be
persisted in the config by issuing `SAVE_CONFIG` command.

### [respond]

The following standard G-Code commands are available when the
[respond config section](Config_Reference.md#respond) is enabled:
- `M118 <message>`: echo the message prepended with the configured
  default prefix (or `echo: ` if no prefix is configured).

The following additional commands are also available.

#### RESPOND
- `RESPOND MSG="<message>"`: echo the message prepended with the
  configured default prefix (or `echo: ` if no prefix is configured).
- `RESPOND TYPE=echo MSG="<message>"`: echo the message prepended with
  `echo: `.
- `RESPOND TYPE=command MSG="<message>"`: echo the message prepended
  with `// `.  OctoPrint can be configured to respond to these messages
  (e.g.  `RESPOND TYPE=command MSG=action:pause`).
- `RESPOND TYPE=error MSG="<message>"`: echo the message prepended
  with `!! `.
- `RESPOND PREFIX=<prefix> MSG="<message>"`: echo the message
  prepended with `<prefix>`. (The `PREFIX` parameter will take
  priority over the `TYPE` parameter)

### [save_variables]

The following command is enabled if a
[save_variables config section](Config_Reference.md#save_variables)
has been enabled.

#### SAVE_VARIABLE
`SAVE_VARIABLE VARIABLE=<name> VALUE=<value>`: Saves the variable to
disk so that it can be used across restarts. All stored variables are
loaded into the `printer.save_variables.variables` dict at startup and
can be used in gcode macros. The provided VALUE is parsed as a Python
literal.

### [screws_tilt_adjust]

The following commands are available when the
[screws_tilt_adjust config section](Config_Reference.md#screws_tilt_adjust)
is enabled (also see the
[manual level guide](Manual_Level.md#adjusting-bed-leveling-screws-using-the-bed-probe)).

#### SCREWS_TILT_CALCULATE
`SCREWS_TILT_CALCULATE [DIRECTION=CW|CCW] [MAX_DEVIATION=<value>]
[<probe_parameter>=<value>]`: This command will invoke the bed screws
adjustment tool. It will command the nozzle to different locations (as
defined in the config file) probing the z height and calculate the
number of knob turns to adjust the bed level. If DIRECTION is
specified, the knob turns will all be in the same direction, clockwise
(CW) or counterclockwise (CCW). See the PROBE command for details on
the optional probe parameters. IMPORTANT: You MUST always do a G28
before using this command. If MAX_DEVIATION is specified, the command will raise a gcode error if any difference in the screw height relative to the base screw height is greater than the value provided.

### [sdcard_loop]

When the [sdcard_loop config section](Config_Reference.md#sdcard_loop)
is enabled, the following extended commands are available.

#### SDCARD_LOOP_BEGIN
`SDCARD_LOOP_BEGIN COUNT=<count>`: Begin a looped section in the SD
print. A count of 0 indicates that the section should be looped
indefinitely.

#### SDCARD_LOOP_END
`SDCARD_LOOP_END`: End a looped section in the SD print.

#### SDCARD_LOOP_DESIST
`SDCARD_LOOP_DESIST`: Complete existing loops without further
iterations.

### [servo]

The following commands are available when a
[servo config section](Config_Reference.md#servo) is enabled.

#### SET_SERVO
`SET_SERVO SERVO=config_name [ANGLE=<degrees> | WIDTH=<seconds>]`: Set
the servo position to the given angle (in degrees) or pulse width (in
seconds). Use `WIDTH=0` to disable the servo output.

### [skew_correction]

The following commands are available when the
[skew_correction config section](Config_Reference.md#skew_correction)
is enabled (also see the [Skew Correction](Skew_Correction.md) guide).

#### SET_SKEW
`SET_SKEW [XY=<ac_length,bd_length,ad_length>] [XZ=<ac,bd,ad>]
[YZ=<ac,bd,ad>] [CLEAR=<0|1>]`: Configures the [skew_correction]
module with measurements (in mm) taken from a calibration print.  One
may enter measurements for any combination of planes, planes not
entered will retain their current value. If `CLEAR=1` is entered then
all skew correction will be disabled.

#### GET_CURRENT_SKEW
`GET_CURRENT_SKEW`: Reports the current printer skew for each plane in
both radians and degrees. The skew is calculated based on parameters
provided via the `SET_SKEW` gcode.

#### CALC_MEASURED_SKEW
`CALC_MEASURED_SKEW [AC=<ac_length>] [BD=<bd_length>]
[AD=<ad_length>]`: Calculates and reports the skew (in radians and
degrees) based on a measured print. This can be useful for determining
the printer's current skew after correction has been applied. It may
also be useful before correction is applied to determine if skew
correction is necessary. See [Skew Correction](Skew_Correction.md) for
details on skew calibration objects and measurements.

#### SKEW_PROFILE
`SKEW_PROFILE [LOAD=<name>] [SAVE=<name>] [REMOVE=<name>]`: Profile
management for skew_correction. LOAD will restore skew state from the
profile matching the supplied name. SAVE will save the current skew
state to a profile matching the supplied name. Remove will delete the
profile matching the supplied name from persistent memory. Note that
after SAVE or REMOVE operations have been run the SAVE_CONFIG gcode
must be run to make the changes to persistent memory permanent.

### [smart_effector]

Several commands are available when a
[smart_effector config section](Config_Reference.md#smart_effector) is enabled.
Be sure to check the official documentation for the Smart Effector on the
[Duet3D Wiki](https://duet3d.dozuki.com/Wiki/Smart_effector_and_carriage_adapters_for_delta_printer)
before changing the Smart Effector parameters. Also check the
[probe calibration guide](Probe_Calibrate.md).

#### SET_SMART_EFFECTOR
`SET_SMART_EFFECTOR [SENSITIVITY=<sensitivity>] [ACCEL=<accel>]
[RECOVERY_TIME=<time>]`: Set the Smart Effector parameters. When
`SENSITIVITY` is specified, the respective value is written to the
SmartEffector EEPROM (requires `control_pin` to be provided).
Acceptable `<sensitivity>` values are 0..255, the default is 50. Lower
values require less nozzle contact force to trigger (but there is a
higher risk of false triggering due to vibrations during probing), and
higher values reduce false triggering (but require larger contact
force to trigger). Since the sensitivity is written to EEPROM, it is
preserved after the shutdown, and so it does not need to be configured
on every printer startup. `ACCEL` and `RECOVERY_TIME` allow to
override the corresponding parameters at run-time, see the
[config section](Config_Reference.md#smart_effector) of Smart Effector
for more info on those parameters.

#### RESET_SMART_EFFECTOR
`RESET_SMART_EFFECTOR`: Resets Smart Effector sensitivity to its factory
settings. Requires `control_pin` to be provided in the config section.

### [stepper_enable]

The stepper_enable module is automatically loaded.

#### SET_STEPPER_ENABLE
`SET_STEPPER_ENABLE STEPPER=<config_name> ENABLE=[0|1]`: Enable or
disable only the given stepper. This is a diagnostic and debugging
tool and must be used with care. Disabling an axis motor does not
reset the homing information. Manually moving a disabled stepper may
cause the machine to operate the motor outside of safe limits. This
can lead to damage to axis components, hot ends, and print surface.

### [temperature_fan]

The following command is available when a
[temperature_fan config section](Config_Reference.md#temperature_fan)
is enabled.

#### SET_TEMPERATURE_FAN_TARGET
`SET_TEMPERATURE_FAN_TARGET temperature_fan=<temperature_fan_name>
[target=<target_temperature>] [min_speed=<min_speed>]
[max_speed=<max_speed>]`: Sets the target temperature for a
temperature_fan. If a target is not supplied, it is set to the
specified temperature in the config file. If speeds are not supplied,
no change is applied.

### [tmcXXXX]

The following commands are available when any of the
[tmcXXXX config sections](Config_Reference.md#tmc-stepper-driver-configuration)
are enabled.

#### DUMP_TMC
`DUMP_TMC STEPPER=<name>`: This command will read the TMC driver
registers and report their values.

#### INIT_TMC
`INIT_TMC STEPPER=<name>`: This command will initialize the TMC
registers. Needed to re-enable the driver if power to the chip is
turned off then back on.

#### SET_TMC_CURRENT
`SET_TMC_CURRENT STEPPER=<name> CURRENT=<amps> HOLDCURRENT=<amps>`:
This will adjust the run and hold currents of the TMC driver.
(HOLDCURRENT is not applicable to tmc2660 drivers.)

#### SET_TMC_FIELD
`SET_TMC_FIELD STEPPER=<name> FIELD=<field> VALUE=<value>`: This will
alter the value of the specified register field of the TMC driver.
This command is intended for low-level diagnostics and debugging only
because changing the fields during run-time can lead to undesired and
potentially dangerous behavior of your printer. Permanent changes
should be made using the printer configuration file instead. No sanity
checks are performed for the given values.

### [toolhead]

The toolhead module is automatically loaded.

#### SET_VELOCITY_LIMIT
`SET_VELOCITY_LIMIT [VELOCITY=<value>] [ACCEL=<value>]
[ACCEL_TO_DECEL=<value>] [SQUARE_CORNER_VELOCITY=<value>]`: Modify the
printer's velocity limits.

### [tuning_tower]

The tuning_tower module is automatically loaded.

#### TUNING_TOWER
`TUNING_TOWER COMMAND=<command> PARAMETER=<name> START=<value>
[SKIP=<value>] [FACTOR=<value> [BAND=<value>]] | [STEP_DELTA=<value>
STEP_HEIGHT=<value>]`: A tool for tuning a parameter on each Z height
during a print. The tool will run the given `COMMAND` with the given
`PARAMETER` assigned to a value that varies with `Z` according to a
formula. Use `FACTOR` if you will use a ruler or calipers to measure
the Z height of the optimum value, or `STEP_DELTA` and `STEP_HEIGHT`
if the tuning tower model has bands of discrete values as is common
with temperature towers. If `SKIP=<value>` is specified, the tuning
process doesn't begin until Z height `<value>` is reached, and below
that the value will be set to `START`; in this case, the `z_height`
used in the formulas below is actually `max(z - skip, 0)`.  There are
three possible combinations of options:
- `FACTOR`: The value changes at a rate of `factor` per millimeter.
  The formula used is: `value = start + factor * z_height`. You can
  plug the optimum Z height directly into the formula to determine the
  optimum parameter value.
- `FACTOR` and `BAND`: The value changes at an average rate of
  `factor` per millimeter, but in discrete bands where the adjustment
  will only be made every `BAND` millimeters of Z height.
  The formula used is:
  `value = start + factor * ((floor(z_height / band) + .5) * band)`.
- `STEP_DELTA` and `STEP_HEIGHT`: The value changes by `STEP_DELTA`
  every `STEP_HEIGHT` millimeters. The formula used is:
  `value = start + step_delta * floor(z_height / step_height)`.
  You can simply count bands or read tuning tower labels to determine
  the optimum value.

### [virtual_sdcard]

Klipper supports the following standard G-Code commands if the
[virtual_sdcard config section](Config_Reference.md#virtual_sdcard) is
enabled:
- List SD card: `M20`
- Initialize SD card: `M21`
- Select SD file: `M23 <filename>`
- Start/resume SD print: `M24`
- Pause SD print: `M25`
- Set SD position: `M26 S<offset>`
- Report SD print status: `M27`

In addition, the following extended commands are available when the
"virtual_sdcard" config section is enabled.

#### SDCARD_PRINT_FILE
`SDCARD_PRINT_FILE FILENAME=<filename>`: Load a file and start SD
print.

#### SDCARD_RESET_FILE
`SDCARD_RESET_FILE`: Unload file and clear SD state.

### [z_tilt]

The following commands are available when the
[z_tilt config section](Config_Reference.md#z_tilt) is enabled.

#### Z_TILT_ADJUST
`Z_TILT_ADJUST [<probe_parameter>=<value>]`: This command will probe
the points specified in the config and then make independent
adjustments to each Z stepper to compensate for tilt. See the PROBE
command for details on the optional probe parameters.