Connection Problems from Astrobox to Prusa i3 MK3


Hello, I need help. The connection to the printer is not established. There is no error message but the spinner is running “connecting”, what can I do?

The following configuration:

  • Raspberry Zero W (External power supply, USB to printer, connection via Wifi to router)
  • Prusa i3 MK3 (Current firmware, via USB to RPI)

What did I do?

  1. astroprint flashed on SD card
  2. Raspberry started and connected to the Wlan
  3. configuration of Astrobox executed via web browser
  4. in the web interface the connection tries to establish with baud rate 15200 and 25000. Neither is possible. The connection is established, the loading spinner is running but nothing happens, no error message either.

I have no idea what to do now. Please help me, thanks.


I’m having the same issue as Brainson, any suggestions?


About speed, in firmware prusa has hardcoded value 115200. Today evening I will try to connect my pi zero with prusa, for now I have it conected to other printer and it is working without problem.


For others, I changed my update channel to beta and updated to:

AstroBox_Touch - v0.14(0)
v0.6.0 - AstroBox Touch UI

and the connection to the printer is now established!


Hi Wojtek,

thank you, unfortunately, this does not help me.

Hi Jonathan,
thanks for your Information. Unfortunately, this does not help me. i use the raspberry pi 3 astroprint software version 0.13(16). which can be accessed via webfrontend.

Any suggestions?


Hmm, just checked my Prusa MK3 and Pi zero W is connecting almost without problem, almost because connecting procedure ending up with rebooting the printer… Of course I tried it during the print :stuck_out_tongue: but after that astroprint is connected and I can move the axis and everything. My firmware version is stock 0.13(16). Maybe check the cable?


thanks, the picture show a screenshot from a smartphone app?


this is web interface opened from chrome on the android phone


just built my new mk3. same issue. i am on the same new code level. what port speed settings are you running?

i am running a pi 3b


115200 and i have the same pi 3+

Yesterday i made an update to new firmware of my mk3 i3 - same problem… The connection is established, the loading spinner is running but nothing happens, no error message either.

I don’t know what else to do.


Having the same issue with mk3 i3. Latest firmware from prusa and latest Astroprint on Pi 3+.
Prusa resets and nothing happens after that. No connection estplised with 115200.


I reflashed my raspberry pi again a few days ago and for me Prusa MK3 is working fine, with both my Raspberry Pi Zero W working as Astrobox and Raspberry Pi 2 working as Astrobox Touch. I can dump my serial logs for comparison if you want.


Do you have the latest firmware on the printer?


No, I have skipped the last update from Prusa. The problem appears only on the last version?


This is our current assumption.


Will check it today after work


So, i updated my Prusa yesterday to 3.5.1-1778 version and my connection between Raspberry Pi zero W is still working fine.
I am running astrobox 0.14(0)


Ok. Just like for us here. I wonder if those having problems have some mods or perhaps SD Cards inserted with a lot of files (which can make boot up slow)


Also Prusa had 2 versions of Einsy board, I have the newest one. Maybe the problem appears on the older boards?


Is there a way to visually see which board we have?