G92 Problem: SOLVED

Hi, I have just rebuilt the hardware on my MakerFarm 12" Prusa, at the same time I upgraded Marlin from 1.1.3 to 1.1.8. I transferred the changes I had made in the old Configuration.h file to the new one as appropriate and amazingly things appeared to work. Of course there had to be a "but" in there, so here it is.

When setting up the servo operated Z probe for UBL, the procedure calls for the print head to be centred over a spot on the bed and then the Z axis lowered so that it is just about touching the bed. All works up to this stage either by moving the print head using the LCD controls or Pronterface.

The next step is to issue a G92 X0 Y0 Z0 to give a 0 reference to the position. Now for the real issue, after issuing the G92 command the LCD position info changes to 0's but as soon as I try to move the head, either through the LCD or Pronterface, it moves away in the positive direction (away from the end stops). It stops on it's own at what I believe is the software defined endstop. A little playing around shows that if I issue only a G92 X0 then only the X axis is affected, Y and Z can be moved normally.

Any idea what I may have done wrong or overlooked in moving from 1.1.3 to 1.1.8?

Edited 1 time(s). Last edit at 06/20/2018 03:27PM by ex-egll.

I started with a clean configuration file and made my changes, this time it worked out OK. Put it down to operator error!

On some occasions after flashing an updated Marlin.
It misses reloading firmware defaults leaving the old configuration data and you need to reset to the Current firmware configuration data.
To do this issue a M502

[marlinfw.org]

Then save the new firmware data using a M500

[marlinfw.org]

Edited 2 time(s). Last edit at 06/20/2018 06:26PM by Roberts_Clif.

Thanks for the response, I usually do the M502, M500, M501 after each download. I think I had some error / bad formatting in the Configuration.h file as when I downloaded the s/w again and modified the settings all went well.