RE:
for me isent the printer... isent display but some elettrical interference... now i try add EMI filter.. all work whit high refresh rate....
I will monitor the situation for a few days and let you know.
What EMI filter did you use? Some kind of plug or a ferrite-core?I think of trying two ferrit cores at both ends of the power cable for testing.
Those are easy to get for a few cents.
A week has passed since my last post.
- I reseated the goldish cables
- I added 6.5mm clip-on ferrite cores to both ends of the power cable
Due to an old GitHub post from Prusa-Support where they told that in the past (MK4) they have some of the screens returned and all of them working fine if grounded correctly - I checked that.
- Tested my socket -> Grounding fine
- changed the short power cord to a longer one where I don't need an extension and added there the ferrite cores as well.
Result: Since a week no occurence of any screen problems in high refresh rate. Maybe it was the crappy extension or the power plug was not sitting correctly in the outlet - at least this was one thing I noticed. I hope it stays like that. Keep you updated, if something changes again!
RE: Core One screen flickering / black screen
I had the same issue. None of the other ideas did help (and TBH while it helped for a few, I don't buy into the EMI topic).
What did help me was reseating the display panel flatflex cable: Remove the display module, open the latches of the flat flex cable, pull it out, clean the contacts with IPA and cotton swab, plug and lock it again.
After that, it did boot and display past the boot loader!
For now I chickened out and went to low refresh rate, until all other issues with my Core One are fixed and I had some time to enjoy it. Then I'll give "high" a chance.
I guess the flatflex was corroded or contaminated prior to/during assembly, increasing surface resistance, and thus degrading the signal. This has more effect the higher the signal frequencies are, thus the effect with "high" refresh rate (and possibly higher sensitivity to HF noise on the power lines).
My argument against issues with grounding or the flat cable to the main board: USB transfer (which is also high-bandwidth and goes over the same cable) was never affected.
Also sent that to Prusa Support, and they were quite curious to relay that to the QA team. I guess they still collect data before issuing a general statement.
RE:
For me, the reconnecting incl. cleaning of the flex cable was not the way to success, though.
I did this as step one, and relatively quick my screen issue came back - only the new power cable and checking the grounding seems to help.
Also on Reddit I see the issues with screen blackouts/flickering are getting more - pretty curious if we're seeing an official statement about this somehow.
RE: Core One screen flickering / black screen
I also celebrated too early. While it is still useable, I noticed that it still flickers and resets the display here and there with "low" refresh rate.
I also have a feeling that it happens more and more often over time. I contacted support, let's see what happens....
RE: Core One screen flickering / black screen
This started for me on a Core One kit shortly after flashing the firmware to 6.3.3.
It would just boot up to a black screen instead of the home screen.
You could hear the clicks, just nothing on the screen.
After reseating both ends of the screen ribbon cable, as noted in other posts, it booted up to the normal home screen.
As to how long it stays this way.......
Note that I have been running this assembled kit for about 2 weeks without any issue prior to this.
The printer has not moved location.
It is not known if the start of the problem was the time running or the flashing of the firmware. Since others have had the same issue on 6.3.2, it suggests time running, so this may pop up again.
RE: Core One screen flickering / black screen
I just had the same problem - flickering screen, goes black, can't even navigate to settings. Changing USB stick didn't help, as well as reseating grounding cables.
I was glad and surprised to resolve the issue by just cleaning the LCD screen thoroughly with a cotton cloth. I think my wet fingers left too much conductive dirt on the screen, which made it recognize false tapping in some place for n the screen.
RE: Core One screen flickering / black screen
Same issue here. Sometimes the screen is black when I turn on the machine. Then I turn it off and turn it on again. And then the screen is ok. But but now it is flickering a lot. It is a pre-assembled machine . ..
RE: Core One screen flickering / black screen
Just to follow up: After sending a video of the phenomenon (mine boots fine and is perfectly useable, but flickers/redraws the screen even in "low refresh rate" mode from time to time) and detailed photos of the wiring (to rule out pinched cables or bad routing), Prusa Support will send me a replacement part.
While I probably have _all_ widespread issues known for Core One at the same time, at least their support is very friendly and helpful.
RE: Core One screen flickering / black screen
I have the same issue on my Core One, and it is only happening when the device is "cold", once the chamber or something gets some heat, it works as expected. It's just abit of a shame that this is not captured during QA or something as the device ain't that cheap...
RE: Core One screen flickering / black screen
I experienced the same flickering issue. It was caused by an improperly inserted Wi-Fi module, which was somehow affecting the display. Once I securely inserted the Wi-Fi module, the display functioned correctly.
RE: Core One screen flickering / black screen
I guess I need to take a look at it then today, I have mine hooked up via ethernet, so not even using the wi-fi on it. Was there something specific with it or, just in general check the connection etc.?
RE: Core One screen flickering / black screen
I also removed the cover of the wifi module and didn't put it back
RE: Core One screen flickering / black screen
I have had a new screen, ribbon cables and xbuddy board from support, nothing has fixed it other than changing the refresh rate
Today I had this reply indicating it’s a firmware issue
Thank you for getting back to me, I am glad to hear that the issue is fixed now! We released a beta firmware just recently that fixes this issue as well and sets a lower referesh rate by default, you might want to flash it from https://github.com/prusa3d/Prusa-Firmware-Buddy/releases/tag/v6.3.4-RC. Thank you for your feedback, we do appreciate it!
RE:
I ran into the same problem (bootup sequence have info displayed correctly, but as soon as bootup finished screen sometime goes black directly, sometime goes black after I touch the nub) this morning with firmware 6.3.3. Did all sort of troubleshooting, nothing really fix the problem, until I flash it with firmware 6.3.4-RC.
Correct link at:
https://github.com/prusa3d/Prusa-Firmware-Buddy/releases/tag/v6.3.4-RC
RE: Core One screen flickering / black screen
I did also install the 6.3.4 RC, and it did fix and actually gave me the prompt that it is detecting the specific issue mentioned, but reading through release notes all it does is that it lowers the refresh rate. Kind of still leaves a bit sour taste how they are handling this, making it feel like that it would say it in the tin that "this issue exist get on with it."
RE: Core One screen flickering / black screen
I have had the same problem with the display. The support told me they will ship a replacement, but no news from them. After reading the release notes of the firmware 6.3.4 RC I have seen they have done some changes to the refresh of the display and days before, when I have opened an issue on GitHub, they told me it is not a bug of the firmware 😀
Anyway after flashing the new firmware it is usable again, but I still see flickering when it changes the page. But then the page is displayed. Personally, I think there is a mix of hardware and firmware bugs, or a stock of displays not gone very well. Let's see what will happen in the coming days.
RE: Core One screen flickering / black screen
Update:
After speaking to support (thanks for the fast response), the advise was to reassemble / reorder the data-cable for the display. Unfortunatly this fixed the display issue for me. 😀
RE: Core One screen flickering / black screen
My Core One (built from a kit) has been in operation for 3.5 months now -- and today it decided to also develop the screen flicker problem. This occurred at the first start after the printer had sat idle for a couple of weeks while I was on vacation. I noticed the problem when I was about to install firmware 6.3.4, still running the prior firmware.
The new firmware mitigates it by detecting the transfer problems and offering to switch to a lower screen refresh rate. That seems to largely fix it, although I still saw a few glitches while running the Input Shaping calibration a bit later. But I don't like the lower screen refresh; for my taste it changes the display interaction from "nice" to "meh".
I would prefer to understand and fix the underlying hardware issue. Since it has changed over time, just by sitting there, it seems likely that there is a bad contact somewhere which slowly oxidized or shook loose. When I removed the display to check that its ribbon connector is properly seated, I noticed a nasty kink in the ribbon cable, but it does not appear to have broken a wire.
Has anyone found a specific root cause in their printer? Should I just go ahead and order a replacement data cable on a hunch?
RE: Core One screen flickering / black screen
My Core One (built from a kit) has been in operation for 3.5 months now -- and today it decided to also develop the screen flicker problem. This occurred at the first start after the printer had sat idle for a couple of weeks while I was on vacation. I noticed the problem when I was about to install firmware 6.3.4, still running the prior firmware.
The new firmware mitigates it by detecting the transfer problems and offering to switch to a lower screen refresh rate. That seems to largely fix it, although I still saw a few glitches while running the Input Shaping calibration a bit later. But I don't like the lower screen refresh; for my taste it changes the display interaction from "nice" to "meh".
I would prefer to understand and fix the underlying hardware issue. Since it has changed over time, just by sitting there, it seems likely that there is a bad contact somewhere which slowly oxidized or shook loose. When I removed the display to check that its ribbon connector is properly seated, I noticed a nasty kink in the ribbon cable, but it does not appear to have broken a wire.
Has anyone found a specific root cause in their printer? Should I just go ahead and order a replacement data cable on a hunch?
Sounds familiar...the black screen issue also showed up the first time after the machine sat on the counter for 10 days while I was on vacation...after that, issues started - but now - since I added ferrite cores and used a different power cable it did not happen again (even on high refresh rate). Fingers crossed.
RE: Core One screen flickering / black screen
since I added ferrite cores and used a different power cable it did not happen again (even on high refresh rate). Fingers crossed.
That sounds promising. Which power cable are you referring to? The display has the ribbon cable which combines power + serial data, plus a ground strap. Did you replace the entire ribbon cable and its connectors? Also, what type of ferrite did you use, and how many passes of the cable through the ribbon? -- Many thanks!
The pinout used on the ribbon cable looks pretty fishy to me, by the way. The fast SPI serial data and clock lines (MOSI, MISO, SCK) are right next to each other, without any shielding. With so many spare wires on the ribbon cable, why didn't the designer interleave these data lines with GND lines?!
This seems like a similar design blunder as what happened with the Love Board on the print head, where heater current and sensitive signals apparently share the same GND return path. Same electronics engineer? 🙄
