flexi-bot/docs/marlin/_gcode/G029-abl-bilinear.md

tag	title	brief	author	requires	group	related	codes	notes	parameters	examples
g029m2	Bed Leveling (Bilinear)	Probe the bed and enable leveling compensation.	thinkyhead	AUTO_BED_LEVELING_BILINEAR	calibration	M420 M421	G29	Any arguments left out of `G29` will use the default values set in `Configuration.h`. [`G28`](/docs/gcode/G028.html) disables bed leveling. Follow with `M420 S1` to turn leveling on, or use `RESTORE_LEVELING_AFTER_G28` to automatically keep leveling on after [`G28`](/docs/gcode/G028.html). To save time and machine wear, save your mesh to EEPROM with [`M500`](/docs/gcode/M500.html) and in your slicer's "Starting G-code" replace `G29` with `M420 S1` to enable your last-saved mesh.	tag optional description values A true Abort leveling procedure in-progress (`PROBE_MANUALLY`) type bool tag optional description values C true Create a fake grid for testing. (`DEBUG_LEVELING_FEATURE`) type bool tag type optional description O bool true Optional. If leveling is already enabled then exit without leveling. (1.1.9) tag optional description values Q true Query the current leveling state (`PROBE_MANUALLY`, `DEBUG_LEVELING_FEATURE`) type bool tag optional description values X true Specify X when setting a mesh value (`PROBE_MANUALLY`). type int/float tag optional description values Y true Specify Y when setting a mesh value. type int/float tag optional description values Z true Specify the Z offset when setting a mesh value. type float tag optional description values W true Write a mesh Z offset. - Use `X`,`Y` or `I`,`J` to specify the point. - Use `Z` to specify the new value to set. type bool tag optional description values S true Set the XY travel speed between probe points. tag type rate float tag optional description values E true - By default G29 will engage the Z probe, test the bed, then disengage. - Include "E" to engage/disengage the Z probe for each sample. - There's no extra effect if you have a fixed Z probe. type bool tag optional description values D true Dry-Run mode. Just probe the grid but don't update the bed leveling data type bool tag optional description values H true Set the square width and height of the area to probe. tag type linear float tag optional description values F true Set the front limit of the probing grid. tag type linear float tag optional description values B true Set the back limit of the probing grid. tag type linear float tag optional description values L true Set the left limit of the probing grid. tag type linear float tag optional description values R true Set the right limit of the probing grid. tag type linear float tag optional description values J true (Without `W`) Jettison the leveling data stored in SRAM and turn off leveling compensation. Data in EEPROM is not affected. type bool tag optional description values V true Set the verbose level type tag int 0-4	pre post code Automatic Probing examples `G29` without arguments uses your default settings. G29 ; Measure the bed post code Probe your configured N x N matrix within the bounds `X50` `Y50` to `X150` `Y150` (verbose). G29 L50 R150 F50 B150 V4 pre post code Manual Probing example Each `G29` command goes to the next step until the whole procedure is done. The `V1` parameter provides a progress report. G29 V1 ; Ready! Go to Point 1, wait... G29 V1 ; Store Z, go to Point 2, wait... G29 V1 ; Store Z, go to Point 3, wait... G29 V1 ; Store Z, go to Point 4, wait... G29 V1 ; Store Z, go to Point 5, wait... G29 V1 ; Store Z, go to Point 6, wait... G29 V1 ; Store Z, go to Point 7, wait... G29 V1 ; Store Z, go to Point 8, wait... G29 V1 ; Store Z, go to Point 9, wait... G29 V1 ; Store Z. Calculate matrix. Activate.

Automatic (Bilinear) Bed Leveling probes the bed at some fixed number of points and produces a mesh representing the imperfections across the bed.

The printer must be homed with G28 before G29.

• For AUTO_BED_LEVELING_UBL see G29 UBL and G26 Mesh Editing.
• For MESH_BED_LEVELING see the G29 MBL page.

Using an electronic probe Marlin can probe the entire bed with a single G29 command. See parameter descriptions and examples below for details.

Manual Probing

{% details %} Auto Bed Leveling now includes a PROBE_MANUALLY option for systems lacking a probe.

PROBE_MANUALLY adds these parameters to G29:

• Q : Query leveling and G29 state
• A : Abort current leveling procedure

To do manual probing simply repeat G29 until the procedure is complete.

The first G29 accepts the same parameters , shown in the Usage section below. The exact parameters available will depend on which style of bed leveling is enabled. (Note: UBL parameters are not covered on this page unless they coincide. See the G29 for UBL page for a full list of its options.)

Before probing the bed:

1. Use G29 Q to get the current status. If G29 isn't idle, abort with G29 A.
2. Use M420 V to view leveling data. You can send M420 S1 to use the existing data.

To probe the bed using G-code:

1. Use G29 to move to the first point for Z adjustment.
2. Adjust Z so a piece of paper can just pass under the nozzle.
3. Use G29 to save the Z value and move to the next point.
4. Repeat steps 3-4 until completed.
5. Use M500 to save the leveling data to EEPROM, if desired.

To probe the bed using your LCD controller: (Requires LCD_BED_LEVELING)

1. Select the Level Bed sub-menu, then choose Level Bed (not Cancel).
2. Wait for Homing XYZ to complete.
3. When Click to Begin appears, press the controller button to move to the first point.
4. Use the controller wheel to adjust Z so that a piece of paper can just pass under the nozzle.
5. Press the controller button to save the Z value and move to the next point.
6. Repeat steps 4-5 until completed.
7. Use Control > Store memory to save the mesh to EEPROM, if desired.

{% enddetails %}

Mesh Editing

AUTO_BED_LEVELING_BILINEAR adds these parameters to G29 for editing mesh points:

• W Write a mesh point. (Ignored during leveling.)
• I X index for mesh point
• J Y index for mesh point
• X logical X of mesh point
• Y logical Y of mesh point
• Z Z to store in mesh. If omitted, current raw Z.