Strange error (freertos configASSERT)  

RE:

Also, now if I try and do an 'Auto Home', it reboots the device.  No error, just a straight up reboot.

Edit: I moved all my axis manually, then did a Z calibration, then auto-home didn't cause a reboot.  But still no idea what happened.

RE: Strange error (freertos configASSERT)

I have seen this error in one other thread:

https://forum.prusa3d.com/forum/postid/664425/

RE: Strange error (freertos configASSERT)

Thanks - my printer is now boot looping.  If I turn it on, it tries to auto home, which immediately causes a reboot.  I'm trying to contact tech support.

RE: Strange error (freertos configASSERT)

I have had that error a few times. I suspect it is the board overheating inside an enclosure. You can watch the board temperature via Home > Info > Sensor Info > Board Temperature.

RE:

My board temp is only 39.8 ... which is nothing.

I've been printing for days without a problem.  I had only JUST started printing today, it was on the first layer still.  Not really enough time to heat up the board presumably.  But nope.  I'm not sure this is board temp.

Especially since just doing an 'auto home' causes it to reboot.

RE:

I have reported this screen to email support on May 27. When I mentioned that I was printing via OctoPrint they only got hung up on that fact and did not offer any explanation for that screen. Just that I should not use OctoPrint and print from USB stick. This went on back and forth a few times. I did follow that advice and used the USB stick, but the error reoccurred nonetheless. During my use I could establish a correllation between temperatures (ambient, inside enclosure, board) and that red screen. It is not specific to a gcode file or a version of the firmware and it happens at different times during a print, sometimes right at the start, if the printer did print something else before and is still warm/hot, sometimes at hour 10 of an 11 hour print. I turned to cooling the board via a fan and this seems to help so far. I have only my own experiences to base this on.
I had no reboots so far.

RE: Strange error (freertos configASSERT)

I'm not using octoprint, so hopefully support will not get hung up on this.  I printed via. PrusaLink at first, and if I try and start the print again via. the USB stick (since PrusaLink uploads to the USB), it causes a reboot.

I've not seen the red error screen since the first time, just reboots.

RE: Strange error (freertos configASSERT)

So perhaps/hopefully we can get some more information on this! 🙂
I have had this screen several times, at least once with every version of the firmware released since the beginning.
Please report back here!

RE: Strange error (freertos configASSERT)

Wouldn't you know it, once I finally got through to support, the auto-home didn't cause a reboot, and I was able to just start up a print.

They wanted me to provide a video of it rebooting, but I didn't think to capture it on video.  So if it happens again, I'll make sure to capture a video.  I re-started the same print that I originally got the error on.  Who knows.

RE: Strange error (freertos configASSERT)

Had this error happen again last night, mid-print (I was in bed), hours into a print.  I tried hitting reset, then I kept getting the power panic cable error instead.

As I have a quick disconnect for all my cables (power and power panic), because my PSU is outside the LACK enclosure, I re-did the quick disconnect for my power panic cable (just in case).  I also decided to update to the 5.0.0 beta4 firmware, since that is also reported to have fixed the power panic issue.

Back to printing.  I will report if I get the original error again.  Side note, printing with input shaping is DAMN fast 🙂

If this IS temperature related, then the buddy board can't handle anywhere NEAR enough heat (modern CPUs go up to 100C before thermal protection kicks in).  Which presumably is made worse due to the thermal transfer pads included in the MK4 (ostensibly, they're supposed to turn the entire metal back into a heat sink, offloading heat from the board into the metal housing - but the metal housing might be getting heated up due its the proximity to the heat bed, making the thermal transfer at best ineffective, at worst, work in reverse, transferring the heat from the housing TO the buddy board).

But I'm still not 100% convinced this is temperature based.