G29 probes only in 1 location

I moved this to a new thread


Roxy directed me to this forum and the Beckdac fork from issue#2040 about the ABL bugs.

I've uploaded the Beckdac to my Ramps 1.4 on a Mendel90, the Y endstop is at Y max and the X endstop is at X max (back right of the bed)

When I send a G28, homing takes place at the back right and then when I send G29, there is no movement in X or Y and the same point is probed each time. I've tried switching the origin from front left to back right with no change. EEPROM and chitchat are disabled.

I also tried a M48 L 10 which Roxy suggested elsewhere and there was no movement in X and Y.

Even with safe Z homing enabled, homing and probing is at back right.

I able to manually jog X and Y but they both stop a bit short of the bed edges.
I've attached a link to my configuration.h and Marlin_main.h and will be grateful for any assistance in fixing this.

configuration.h http://pastebin.com/T6u1Gghk
marlin_main.cpp http://pastebin.com/NbATys7k

Your home limit switches are at the Max side of the bed for X & Y ???? And when you say it only probes one point, does it probe that same point multiple times?

I'm not positive this is the problem, but you have:

Code:

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#define min_software_endstops true // If true, axis won't move to coordinates less than HOME_POS.
#define max_software_endstops true  // If true, axis won't move to coordinates greater than the defined lengths below

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And below you have:

Code:

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#define MANUAL_X_HOME_POS 195
#define MANUAL_Y_HOME_POS 195
#define MANUAL_Z_HOME_POS 0

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Let's turn off the software end stops until we get this figured out!

Update: I just noticed this:

Code:

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    // set the rectangle in which to probe
    #define LEFT_PROBE_BED_POSITION 7
    #define RIGHT_PROBE_BED_POSITION 140
    #define FRONT_PROBE_BED_POSITION 13
    #define BACK_PROBE_BED_POSITION 181
...
  // these are the offsets to the probe relative to the extruder tip (Hotend - Probe)
  #define X_PROBE_OFFSET_FROM_EXTRUDER -38    // Probe on: -left  +right
  #define Y_PROBE_OFFSET_FROM_EXTRUDER -8    // Probe on: -front +behind
  #define Z_PROBE_OFFSET_FROM_EXTRUDER -1.11  // -below (always!)

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We might be running into trouble because of the Probe Offsets. Let's try changing these to:

Code:

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    #define LEFT_PROBE_BED_POSITION 50
    #define RIGHT_PROBE_BED_POSITION 125
    #define FRONT_PROBE_BED_POSITION 50
    #define BACK_PROBE_BED_POSITION 125

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Also, when you do the G29, it might be useful to do it with and without the T option. The loops behave slightly differently depending upon whether you are trying to produce a Bed Topology report.

Quote:

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Your home limit switches are at the Max side of the bed for X & Y

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Sorry, I confused myself. X endstop is at max end but Y is at min (front)

Quote:

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does it probe that same point multiple times?

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yes although it thinks that it is moving to different points. I think that the problem starts with G28, I can't get it to home any where else but back right of the bed irrespective of enabled/disabled safe z homing which should home in the centre? I've also tried enabling manual home positions with different values but the home position doesn't change.

I also turned off software endstops and changed the probe points as you suggested but it's made no difference. I'm sending plain G29 without topology report.

It would also be helpful to see the output of the G29 with a high verbose level: G29 T V 4 We should be able to see if it is looping through all the points it is supposed to.

Here's the log, probing took place in one location only (back right)

Code:

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15:16:45.706 : N538 G28 *61
15:16:49.653 : ok
15:17:00.698 : N544 G29  T V4 *33
15:17:00.698 : Roxy's Enhanced G29 Auto_Bed_Leveling Code V1.81:
15:17:00.713 : Full support at http://3dprintboard.com
15:17:06.002 : Bed x: 50.00 y: 50.00 z: 1.12
15:17:12.039 : Bed x: 87.00 y: 50.00 z: 1.11
15:17:18.061 : Bed x: 124.00 y: 50.00 z: 1.12
15:17:24.098 : Bed x: 50.00 y: 87.00 z: 1.11
15:17:30.135 : Bed x: 87.00 y: 87.00 z: 1.11
15:17:36.172 : Bed x: 124.00 y: 87.00 z: 1.11
15:17:42.210 : Bed x: 50.00 y: 124.00 z: 1.11
15:17:48.262 : Bed x: 87.00 y: 124.00 z: 1.11
15:17:54.300 : Bed x: 124.00 y: 124.00 z: 1.12
15:17:54.300 : Eqn coefficients: a: 0.00 b: -0.00 d: 1.12
15:17:54.315 : Mean of sampled points: 1.112673
15:17:54.315 :
15:17:54.315 : Bed Height Topography:
15:17:54.315 : --0.00392 --0.00580 +0.00233
15:17:54.315 : +0.00045 --0.00049 --0.00017
15:17:54.315 : +0.00326 +0.00201 +0.00233
15:17:54.315 :
15:17:54.315 : planeNormal x: -0.00 y: 0.00 z: 1.00
15:17:54.315 :
15:17:54.331 : Bed Level Correction Matrix:
15:17:54.331 : 1.000000 0.000000 0.000021
15:17:54.331 : 0.000000 1.000000 -0.000068
15:17:54.331 : -0.000021 0.000068 1.000000
15:17:56.031 : ok
15:17:56.031 : echo:endstops hit:  X:125.00 Y:108.00 Z:1.12

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The output should look like:



Bed Level Correction Matrix:
1.000000 0.000000 -0.000449
0.000000 1.000000 0.000548
0.000449 -0.000548 1.000000
echo:endstops hit: Z:4.72

It should say the Z endstop was hit... But not the X & Y. I think that is the explanation for why it is refusing to move the X & Y.

I don't know what your end stop configuration is... But switching one of these might make it go:

const bool X_MIN_ENDSTOP_INVERTING = false; // set to true to invert the logic of the endstop.
const bool Y_MIN_ENDSTOP_INVERTING = false; // set to true to invert the logic of the endstop.

or maybe...

const bool Y_MAX_ENDSTOP_INVERTING = true; // set to true to invert the logic of the endstop.
const bool Z_MAX_ENDSTOP_INVERTING = true; // set to true to invert the logic of the endstop

PS. Make sure you have a finger on the reset button when you tell it to home! Like I say, I don't know how your end stops are wired. But it would be unusual to have some one way and others a different way. My guess is flipping the true and false on either the Min or the Max might make it go.

Thanks, that helped. I got myself into a bit of muddle with the min/max and direction of the Y axis

Quote:

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Originally Posted by paulnd

Thanks, that helped. I got myself into a bit of muddle with the min/max and direction of the Y axis

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So??? Is it working? If so... You can start increasing the size of the probe area! It is better to have it probe a large area, but because we didn't know what was wrong, we needed to shrink that to make sure that wasn't causing problems!

yes, it's working. thanks for your help!