Printer Cannot Complete A Job, Always "lost communication w/ MCU"
Looking for any help / guidance with problem I've been having for couple days now. Whenever I start a print job, sometimes it could be minutes, sometimes it could be an hour, klipper will always shutdown with a "lost communcation w/ mcu" error. It's been an issue with toolheads, I've seen both T0 and T1 instances, it's been Beacon. It's not the same thing every time, but it's always a "lost communciation w/ MCU" shutdown and the printer crashes. Attaching latest klipper log, but I am not experienced enough w/ klipper to glean much from it. Anyone have guidance for this kind of issue? It almost seems like a hardware problem, mabye w/ octopus board or somehting becuase it's not usually the same malfunctionioning device, but it's always some malfunctioning device.
Solution:Jump to solution
Thank you for the input, and you were pretty much spot on. It was USB system. I was able to narrow it down to that, shoudl have updated this thread that I was able to address the problem.
3 Replies
Generally speaking this is a power or capacity issue.
Usually it means there are too many USB devices and you need a powered USB hub to run them.
If you already have a hub and it is powered then the HUB is an STT device and you need an MTT hub to handle a printer with lots of MCUs because of timing constraints.
You can check for the chipset a hub uses when it advertises and look if its MTT. Personally that solved 99% of disconnect issues I ever had.
If you already meet this minimum requirement you may have a short somewhere that's taking everything offline.
I once had my 5v power shorted to one of teh 2 USB-A data lines and it would kick everything offline intermittently.
I could tell this was the problem cause only a full power cycle would fix it where as a hub not being powered stuff would come back.
Solution
Thank you for the input, and you were pretty much spot on. It was USB system. I was able to narrow it down to that, shoudl have updated this thread that I was able to address the problem.
@rms497 Awesome, at least now anyone else that comes across it will know. Good luck in your printing adventures.