Can't use copy mode M605 S2 via back USB port

Hey there,

I connected my J1 via a Raspberry on the back USB print to print via OctoPrint. It works pretty well so far, except I can’t print in copy mode.
These are the very first uncommented lines of gcode:

M82 ;absolute extrusion mode

;Start GCode begin
;M605 S0 ;Full control mode
;M605 S1 ;Auto-park mode
M605 S2 X150 R0
;M605 S3 ;Mirror
M140 S45 ;Start Warming Bed

My slicer is prusa, but I don’t see any difference to the first lines of Luban Slicer.
I wonder because the mirror mode works fine.
What I’m missing?



So I sliced a model in Luban an selected “Copy Mode”. When I print the file via backside USB connection only the left extruder print the object. But both hotends are heated.

But when I put the same file on a USB stick an just hit the touchscreen and select the file, the copy mode is already enabled (as expected) and it also print in copy modus.

So why cant I print via USB connection (without USB stick, or touchscreen) the copy mode?
The mirror mode works fine via USB connection also.

I suspect this is probably related to the issue’s I’m having with OctoPrint and any multi-extruder print.

Single extruder stuff typically goes through just fine.

Here are my actual findings:

  1. M605 S2 command works via USB with FW v2.3.5, the oldest available FW. Any next FW (started v2.4.8 on screen/ v2.1.28 via USB) does not work correctly with M605 S2 command. (Update: The older FWs are no more available for download but I can share it.)
  2. Any other modes (S0, S3 tested) seems to be OK.
  3. OSS versions of FW started as v 2.2.11 doesn’t work as well.
    Can local staff check which change (v2.3.5/v2.4.8) can be the key issue here?

Note: Similar issue has Marlin itself (but with S2 and S3 modes of M605 command). One possibility is that this issue is “imported” from Marlin.

1 Like

Did you contacted with snapmaker support team? did you created ticket and get response from them?

Yes, I did but no response. Sad is here is no real response to much older tickets.

Bug update:
The bug is caused by commit c6c56a2: Pref: right extruder do not wait temper in the middle of bed when work in copy mode.
Since this commit, copy mode is not working via USB, commits works as expected.