Basic Information: Printer Model:Voron 2.4 MCU / Printerboard: 2-SKR 1.4 controllers, EBB SB2209 USB V1.0, AFC-Lite V1.1 Host / SBC: BTT pi klippy.log klippy (2).log (4.0 MB) Fill out above information and in all cases attach your klippy.log file (use zip to compress it, if too big). Pastin…

performed a roll back. cd ~/klipper sudo service klipper stop git checkout 126275d1f sudo service klipper start verified 2209 uart address was 0. Everything is working.

It seems that PREP command does not belong to Klipper. Git version: 'v0.13.0-193-gbcd451095-dirty' Untracked files: klippy/extras/AFC.py, klippy/extras/AFC_BoxTurtle.py, klippy/extras/AFC_HTLF.py, klippy/extras/AFC_NightOwl.py, klippy/extras/AFC_QuattroBox.py, klippy/extras/AFC_assist.py, klippy/ex…

From the link in my last post. Update Implications Another very important aspect is that Klipper’s internal methods are not guaranteed to remain stable. As a result, Klipper’s internal functions may change with each update. This can easily lead to a non-functional system (errors at startup) or som…

I don’t use BoxTurtle. You’re not alone. [Other]: Internal error on command:"PREP" at startup after AFC install opened 12:35PM - 20 Aug 25 UTC (UTC) [image] JacquesRooswinkel …

You should post your experience as a reply to the “issue report” linked above at github. The devs might be waiting for conformation that Klipper updates break their addins.

The main devs of both AFC software and Happy Hare are aware of the changes and announcements have been posted to both their Discord servers, along with instructions to roll back to a previous Klipper commit until the software can be updated for the new Klipper.

[image] fargkenob: performed a roll back. cd ~/klipper sudo service klipper stop git checkout 126275d1f sudo service klipper start verified 2209 uart address was 0. Everything is working. Armored Turtle discord provided a helpful solution.

So the rollback was his solution?

So the author tells the users to downgrade Klipper (and missing improvements) instead of fixing his code.

Internal error on command:"PREP"

General Discussion

fargkenob August 20, 2025, 3:38pm 3

the command is used to PREP the Armored Box Turtle using an AFC-lite board with btt 2209’s

System was working fine until update.

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Internal error on command:"PREP"

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