[Tip] disable the prusa mk3 firmware reset

General
1

As i learned on a livestream by tom:

you can disable the reset with:

;C32u2_RMD

for enabling again

;C32u2_RME

So then you shouldn't need a cable with the power lines cut as far i understand.

source:
https://cfl.prusa3d.com/display/PI3M3/UsbSerial+commands

2

The backpowering "issue" is something different than the printer reset on USB connection.

But I'll have a look on that tube...

3

ah ok
haven't tested it yet.
thought this maybe solves this issue

4

In all, this is a SD card simulator. So you don't have the full functionality of OctoPrint.

If you just want to cut the Vcc in the USB, you can use something like this:

https://www.amazon.de/PortaPow-USB-Power-Blocker/dp/B094FYL9QT/ref=asc_df_B094FYL9QT/?tag=googshopde-21&linkCode=df0&hvadid=526320444366&hvpos=&hvnetw=g&hvrand=1687655464642959149&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=1004707&hvtargid=pla-1480478050957&psc=1&th=1&psc=1

5

As I have seen at 2:10:10, the Prusa is resetting at the moment this box establishes the USB connection.

6

Yeah sadly Power BLough-R from Brian Lough on Tindie
isn't actually available.

7

IIRC Prusa doesn't have the same issues with packpowering as Creality machines, but the reset on serial connection could be problematic if you are say printing from SD card and decide to connect OctoPrint while it's printing. That would reset the board and as a result kill your SD print.

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8

Is there a way to send those commands via Octoprint? The semicolon seem to be filtered by the terminal windows (it may think it is the beginning of a comment).

9

Well you can create a text file for each command with the ending .gcode and then print it.
I guess when it is in a file there should be no filtering.
@foosel ?

10

OctoPrint will strip gcode comments before sending it to the printer, so I don't think you'll be able to send these commands through it.

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