[BUG] Busy Status on printer

[Elcar903]

Printer model

MK3S/+

MMU model

MMU3

Firmware versions

3.14.1-8237

Upgrades and modifications

none

Printing from...

PrusaConnect

Describe the bug

Printer shows "Busy" status on Prusa connect when its not busy and you cant start a print either from the app or from the manual controls on the printer.

Using PrusaLink 0.8.1 and MMU3 (3.0.3)

I have tried to re-flash the firmware to 3.14.1 (3.0.3) on both the printer and MMU3 unit and this doesn't fix it.
I downgraded the firmware to 3.14.0 (3.0.2) and it fixes the issue.

Sometimes resting the printer with the "X" button will fix it or resetting just the MMU3 will fix it but not always.

How to reproduce

Just turning on the printer and it goes into the Busy state.

Expected behavior

turn on the printer and being able to use it without going into busy state when its not doing anything.

Files

No response

[gudnimg]

Did the printer visually indicate in any way why its busy? Was there any message on the last line on the screen? Or was the printer showing perhaps a full screen message?

Usually the printer is only in busy state on boot-up if the printer is waiting for user feedback.

[Elcar903]

No message on the screen, everything looks normal.

I let it sit over 30 min after boot up with no changes to the status.
It wont even let me print from the SD card when it shows "Busy" on Prusa connect.

Re-flashing the firmware to Firmware 3.14.1 (3.0.3) to see if the first time it didn't do soothing correctly
on both the MK3s and MMU3 as well as doing a factory reset on both devices after
the re-flash did not fix the issue either.

Some times after several resets/power cycles it will show correctly and works just fine,

I downgraded the firmware back to Firmware 3.14.0 (3.0.2) and everything works perfectly with no issues like before.

I have spent at least 6 hours messing with everything I can think of,
Checking hardware, wires, connectors , etc. and followed all the trouble shooting guides and nothing has fixed it for me.

[3d-gussner]

@Elcar903 Thanks for the update and your time troubleshooting it.
We have been troubleshooting this issue as well and I have found last night what is causing it.

Short summary:
PrusaLink 0.8.1 tries to get the MMU firmware version and expects the response in a very strict format. While all previous MMU version matched that format the MMU3.0.3+896 frankly doesn't.

We are working on a solution.

Would you be willing to try a "hot-fix"?

[Elcar903]

@3d-gussner I wouldn't mind trying it.

[3d-gussner]

@3d-gussner I wouldn't mind trying it.

I prepared a fix prusa3d/Prusa-Link#1009 but not sure how long it takes to get this tested and released.

Do you have ssh to your RPi Zero W? If so you could change the few lines directly.

[Elcar903]

no I dont have SSH,
for now I will wait for a fix for it, the new firmware has features I like but I can print without for now.

[Paulg5678]

I'm seeing this issue as well, was working fine after firmware update until i did a power cycle, now permanently stuck in BUSY mode.

Is the current workaround just to flash back to the old firmware until the 0.8.2 prusaLink is released?

[3d-gussner]

@Elcar903 @Paulg5678 Please send me an email.

[saskot]

Hi i am having the same issue MK3S mmu2s. happend with update to 3.14.1-8237 also did update on rasp. System Version

Python

3.11.2 (main, Mar 13 2023, 12:18:29) [GCC 12.2.0]

[3d-gussner]

@saskot See #4818 (comment) or send me an email.