Auto_Bed_Leveling: Enhanced G29 command

[Roxy]

Will just typing G29 V 4 into my start g-code make it work or will I need to do more?

The default is a 3x3 grid if you don't specify the number of points. So you would want G29 u4 T V4 or G29 P4 T V4 depending on where you got your code from.

You might want to try the RCBugFix file at www.github.com/MarlinFirmware/Marlin and turn on Mesh Bed Leveling. That might help you with the not flat bed.

[inventabuild]

Hi Roxy,

I finally got my auto bed leveling working. Here's a video demonstrating it:

https://www.youtube.com/watch?v=AnHCrnXoj9k

and here's the more lengthy post that includes a little more detail about the setup:

https://forum.lulzbot.com/viewtopic.php?f=16&t=4309

When will auto bed leveling with matrix be ready? I'll have to do some mods to my setup when that comes out.

Thank you very much for your help!!!

Mitch

[Roxy]

When will auto bed leveling with matrix be ready? I'll have to do some mods to my setup when that comes out.

Thank you very much for your help!!!

It is difficult to predict. The problem is free time that can be allocated to it. But I'm hoping it will be available for download in a couple of months.

[inventabuild]

It is difficult to predict. The problem is free time that can be allocated to it. But I'm hoping it will be available for download in a couple of months.

Hi Roxy, is auto bed leveling with matix available yet or is it still a work-in-progress? I could really use that functionality; hence the reason for my question.

[TopJimmyCooks]

Hi Roxy,
I am having a problem getting my G29 to probe four points only. This is the BeckDac fork from about 15 months ago. If it would help to update to newer marlin I could do so.

I have the following in configuration.h. Thanks for any help!

#define AUTO_BED_LEVELING_GRID  // with AUTO_BED_LEVELING_GRID, the bed is sampled in a
  // AUTO_BED_LEVELING_GRID_POINTSxAUTO_BED_LEVELING_GRID_POINTS grid
  // and least squares solution is calculated
  // Note: this feature occupies 10'206 byte
#ifdef AUTO_BED_LEVELING_GRID


    // set the rectangle in which to probe
    #define LEFT_PROBE_BED_POSITION 0
    #define RIGHT_PROBE_BED_POSITION 110
    #define BACK_PROBE_BED_POSITION 195
    #define FRONT_PROBE_BED_POSITION 0


    // set the max number of grid points per dimension
    // The G29 command defaults to 3 if nothing is specified.  But setting the number of probed 
    // points higher is very useful when getting a Bed Topology Report  (G29 n 5 T)
    #define AUTO_BED_LEVELING_GRID_POINTS 2


    // Uncomment one of the following four lines so the Bed Topology Report can produce a map
    // that relates accurately to your bed orientation.  


    //#define ORIGIN_FRONT_LEFT
    //#define ORIGIN_BACK_LEFT
    //#define ORIGIN_FRONT_RIGHT
    #define ORIGIN_BACK_RIGHT


  #else  // not AUTO_BED_LEVELING_GRID
    // with no grid, just probe 3 arbitrary points.  A simple cross-product
    // is used to esimate the plane of the print bed


      #define ABL_PROBE_PT_1_X 0
      #define ABL_PROBE_PT_1_Y 0
      #define ABL_PROBE_PT_2_X 115
      #define ABL_PROBE_PT_2_Y 0
      #define ABL_PROBE_PT_3_X 115
      #define ABL_PROBE_PT_3_Y 190


  #endif // AUTO_BED_LEVELING_GRID

[Roxy]

The default number of points (if you don't specify a number) is 3. You should be able to say: G29 n 2 to get 4 points (2x2) probed. Please be aware that it would be: G29 P 2 in the GitHub code. You should probably leave the

#define AUTO_BED_LEVELING_GRID_POINTS 5

Just because you have space declared for a bigger set of points doesn't mean you have to use them.

I do suggest you load up the RCBugFix when you have time. It has a lot of good stuff in it. And you will need to have your settings crossed over to it's Configuration.h format to run the Unified Bed Leveling that is coming out soon.

[TopJimmyCooks]

Ok, I did the change to #define AUTO_BED_LEVELING_GRID_POINTS 5

I went to pronterface, ran G28.
when I sent G29 n 2 i got this error message:

>>> g29 n 2SENDING:G29 N 2
Error:Line Number is not Last Line Number+1, Last Line: 0
[ERROR] Error:Line Number is not Last Line Number+1, Last Line: 0


Resend: 1

I'm searching for information on this error but not getting anything definite - Thanks for any ideas.

[TopJimmyCooks]

Ok, I transferred all the information from configuration.h to the new one for RC6 bugfix and flashed it. I can't get it to home to the back right as my endstops are set up for (and as a lot of makerfarm I3v's are set for) previously there was a place to define the home as back right which I don't find in the new configuration.h. I saw somewhere a positive/negative homing direction setting, I will go look for that.

[Roxy]

I went to pronterface, ran G28.
when I sent G29 n 2 i got this error message:

This is a problem with the GCode protocol. You can't send a capital N because that says what line of GCode was transferred. That is why a lower case 'n' is used. But because it was causing so many problems (like you just ran into), the parameter was changed to 'P' in the new code.

(If you look at what the error code says... You actually sent a Capital N. Probably a lower case 'n' would have behaved as expected.)

[TopJimmyCooks]

If I ignore pronterface, which forces all alpha characters to UC, and use a gcode file with the LC n will it work? i'm on 1.1 rc 6 bugfix now. is the P implemented in rc 6 or yet to be changed?

I would go ahead and just try it but I'm still wrestling with the allowable probed area of the bed vs probe offset vs homing at the right back thing.

[....later]
OK, reflashed back to old DACB fork and ran a test gcode file with "G29 n 2" and it worked, probed four points as expected. I'm going to stick with this until I get a better understand the new bed layout setup in RC bugfix. Thanks very much for the help and for your work as a Dev!