[BUG] Z Stealthchop is destroying baby steps

[emaayan]

Bug Description

when StealthChop for z is enabled trying to do babystepping doesn't work, initially the motor will move just a little then it will stop moving completely and even after the build it won't move at all unless reset

My Configurations

this is marlin build 2.0.x from 18.01.2020

Marlin.zip

Steps to Reproduce

1. enable z stealthchop and babystepping
2. start a print , during pring adjust the knob on the z-offset

Expected behavior:
z axis moving according the knob

Actual behavior:
z axis stops moving after a few turns and is completely disabled afterwords

Additional Information

hardware is tmc 2208 skr 1.4

[thinkyhead]

Please test the bugfix-2.0.x branch to see where it stands. If the problem has been resolved then we can close this issue. If the issue isn't resolved yet, then we should investigate further.

[emaayan]

Please test the bugfix-2.0.x branch to see where it stands. If the problem has been resolved then we can close this issue. If the issue isn't resolved yet, then we should investigate further.

this w as tested on a firmware from the 18th..

[emaayan]

Please test the bugfix-2.0.x branch to see where it stands. If the problem has been resolved then we can close this issue. If the issue isn't resolved yet, then we should investigate further.

this w as tested on a firmware from the 18th..

i've updated the bug when i said 18 i mean from the 18th this month as in marlin 2.0.x

[thinkyhead]

This issue is confirmed. For now the solution is to lower your babystep multiplier setting and re-flash. Try dividing it in half as a starting-point.

[sjasonsmith]

I have been unable to reproduce this. I tried with my original SKR 1.3 configuration, then with several modifications to get closer to the posted configs. I even swapped out my 2208 for the specific module I was using to test shutdowns with linear advance.

During my tests I had visible Z activity due to bed leveling, and also tested in vase mode to allow testing during continuous Z movement.

I'm out of ideas to get it to happen on my machine. My goal was to reproduce the issue, the do a mixed-signal capture of the motor outputs and the step pulses at the same time. My hypothesis is that prior to shutdown, we will see two step pulses unreasonably close together just before the motors turn off.

[sjasonsmith]

Can somebody experiencing this issue post an STL and sliced gcode that you can reproduce it with? Maybe there is capability used in the file (Z-hop maybe?) that behaves poorly along with babystepping.

[emaayan]

Can somebody experiencing this issue post an STL and sliced gcode that you can reproduce it with? Maybe there is capability used in the file (Z-hop maybe?) that behaves poorly along with babystepping.

perhaps it's an issue with 1.4? i don't think it's related to a specific g-code i have several of them

[InsanityAutomation]

Mine hasn't made it here from China yet unfortunately....