[BFW-5600] [BUG] Flashing screen on MINI 5.1.0 alpha

[Erik262]

Printer type - MINI

Printer firmware version - original

Original or Custom firmware - 5.1.0 alpha

Optional upgrades - Filament Runout Sensor

USB drive or USB/Octoprint USB and also same happens via PrusaConnect

Describe the bug Right after the Warning message about Alpha Firmware, the whole screen keeps refreshing every 3 second

How to reproduce This error happened right after flashing the alpha firmware

Expected behavior No permanent flashing screen UI

G-code Not necessary

Crash dump file The printer keeps printing fine without any issues.

Video https://github.com/prusa3d/Prusa-Firmware-Buddy/assets/11977647/d3cedbca-3a62-4501-be4d-6dd3035e3af1

[diminDDL]

I have the exact same issue. I believe it's a signal integrity issue, as I have scoped out the data lines during the bootloader/alpha firmware warning screens (when this issue is not present) and then the main home screen.

Boot screen signals:

Boot screen signals, zoomed in:

Home screen signals:

Home screen signals, zoomed in:

Home screen signals, zoomed in (different section):

As can be seen above, the display updates during the boot screen phase all have pretty good edges no overshoots and in general you can clearly see a digital signal there. The home screen updates show a very ringy and triangular looking signal. So it appears that during an effort to either increase the screen refresh rate or while porting from a different display, some clocking settings have been set slightly too high where it works fine on some machine, but breaks on certain others.

[Ferrugius]

Same here.

https://github.com/prusa3d/Prusa-Firmware-Buddy/assets/16562546/e92f2e83-7b68-4016-9bde-4aaa6ab138f2

[D3nkis]

Hi folks, the issue is same.

[PhilippeGalid]

Hi after Update to MINI 5.1.0 alpha Firmware i have the same problem, Flashing Screen, i go now back to the old Firmware

[crazy-hair]

Same here. Printer seems to operate normally other than the fact that it constantly refreshes the screen. It's interesting how it doesn't happen in certain menus, like the z adjust or the alpha warning.

[R4ynor]

I have the same problem, but in my case when a motor is running I can here it glitching. The worst case is the extruder motor:

https://github.com/prusa3d/Prusa-Firmware-Buddy/assets/9499061/5cb1af4c-beb1-4422-be97-9e76044ef2ae

[Lino77]

I have this problem only on the display, 3.2" and on the 2.8"from Fysetec. On the 2 original from Prusa LDO A01 and A03 that I have and one from Bigtreetech I do not have this problem.

[CuriousTimo]

So @R4ynor seems to be running an original Prusa Mini. But are the others running an original printer or a Fysetc clone? And if it's a clone, what screen? The 3.2" or 2.4"?

[fabry-68]

I have the same problem on 2 x Fysetc clones with 3.2" LCD.

[ZeekWorld]

Same, Fysetc 3.2".

[Audiard-Jerome]

Same, Fystec 2.8"

[Ferrugius]

Fysetc 3.2" here.

[CuriousTimo]

So it looks like this issue is mainly seen on Fysetc displays.

@R4ynor I can see that your X-axis is using a Prusa Stepper motor. Are you running a replacement Fysetc display? Or is there anything else special our your Mini? Is it an original Prusa Mini?

• If for instance, you are running a replacement display or buddy board by Fysetc we can narrow the issue down.

• Since this issue was not there on the older firmware I'm wondering if there are changes in the code related to the st7789 display. Or are we maybe looking at an SPI related issue that the Fysetc display is venerable to?

[KR4DIO]

Are you running a replacement Fysetc display? Or is there anything else special our your Mini? Is it an original Prusa Mini?

I'm not the OP, but I have the same issue with the fysetc 3.2" display. It's the only non-Prusa part on a bone stock original Prusa Mini. I think I still have the original display board around here somewhere, so I plan to compare to see if there's any difference in signal termination. I'll also try a ferrite choke around the ribbon cable.

[xXNoceboXx]

I have the same issue with Fystec 2.8 screen

https://github.com/prusa3d/Prusa-Firmware-Buddy/issues/3301#issue-1908538040

[nolookjones]

same issue with a Fysetc 2.8 screen...the printer still works though except for this

[Gabri988]

Same problem...Fysetc 3.2 lcd

[EnnjiBennji]

same issue with a Fysetc 2.8 screen

[g8toparadise]

Any news from Prusa on this issue ? Since it seems to happen mainly on clone do you think we can hope for a correction ?

[SteynGuelen]

Same issue here with 2.8 Fysetc screen.

[diminDDL]

Any news from Prusa on this issue ? Since it seems to happen mainly on clone do you think we can hope for a correction ?

Prusa does not actually develop in this repository, this appears to be just a mirror they push to every major release, so we will likely see/hear about it after the next release.

[CuriousTimo]

As a quick test, I have ordered a new LCD screen made by Bigtreetech.

I can confirm that swapping over only the LCD from a Fysetc one to a Bigtreetech fixes the issue. Everything else including the ribbon cable was left in place.

So the flashing issue seems to be with the Fysetc screens.

I doubt that Prusa will fix a clone hardware-related issue. So in my personal situation, this will be my permanent fix.

[KR4DIO]

I can confirm that swapping over only the LCD from a Fysetc one to a Bigtreetech fixes the issue. Everything else including the ribbon cable was left in place.

Did you swap the LCD panel onto the fysetc board? Or swap the whole assembly? If the latter, are there any obvious differences in the components between the pin header and FPC connector?

[ZeekWorld]

As a quick test, I have ordered a new LCD screen made by Bigtreetech.

I can confirm that swapping over only the LCD from a Fysetc one to a Bigtreetech fixes the issue.

Everything else including the ribbon cable was left in place.

So the flashing issue seems to be with the Fysetc screens.

I doubt that Prusa will fix a clone hardware-related issue. So in my personal situation, this will be my permanent fix. Can you share the link for the screen?

[g8toparadise]

@CuriousTimo Thanks for the head up !!!! Can you confirm the screen I linked is suitable ?

@ZeekWorld https://fr.aliexpress.com/item/4001267632446.html?spm=a2g0o.productlist.main.21.3134dT0MdT0MHB&algo_pvid=fd49074d-0f17-481f-a8d9-02704fd9cf50&algo_exp_id=fd49074d-0f17-481f-a8d9-02704fd9cf50-10&pdp_npi=4%40dis%21EUR%2119.11%2112.8%21%21%2119.64%21%21%40211b440316974778766633708e93f8%2110000015531261574%21sea%21FR%21731355889%21&curPageLogUid=eAsfLLECGhkn

[CuriousTimo]

I can confirm that swapping over only the LCD from a Fysetc one to a Bigtreetech fixes the issue. Everything else including the ribbon cable was left in place.

Did you swap the LCD panel onto the fysetc board? Or swap the whole assembly? If the latter, are there any obvious differences in the components between the pin header and FPC connector?

I only swapped the LCD. Nothing else. I will have to check if I can find any obvious differences between the two.

@g8toparadise Yes it is item 4001267632446.

[PhilippeGalid]

Did we have to buy the bigtreetech Display to fix the Problem on the Prusa Mini Clone, or you think Prusa will fix the Problem with a New Firmeware for the Display, did we have to what or buy now a new Display is cost 20euro. Bescause Impute Shaping is a very cool future in the New Firmware,50% faster Print.

https://biqu.equipment/products/clone-prusa-mini-buddy-control-board-integrated-tmc2209-driver-mini-lcd28-v1-0-switch-3d-printer-parts-for-prusa-mini-printer

[R4ynor]

In my case I put this Bigtreetech display in my original Prusa as a replacement and couses the flashing problem. I'll try tomorrow to swap the LCD in the original board with this one like @CuriousTimo.

[R4ynor]

I can confirm that the problem is related to the PCB and not with the LCD from bigtreetech, my printer now works flawlessly.

[CuriousTimo]

Update with bad news:

My BTT LCD worked flawlessly for about three days. Last night I noticed it started flashing.

• I leave my mini on 24/7
• Tried a restart
• Tried going back to the Fysetc LCD

It keeps flashing now every time.

Unfortunately, I do not have the equipment to do any further in-depth measuring. But I think that @diminDDL is on the right track that in the newer firmware something has changed causing issues on the data lines and clock signal.

The clone LCD screen seem to be less tolerating.

[PhilippeGalid]

There is a New Fireware out now did the Fysetec LCD problem fix it now with the New Firmware ? Did some tested ?

[KR4DIO]

There is a New Fireware out now did the Fysetec LCD problem fix it now with the New Firmware ? Did some tested ?

No change here with the Fysetc 3.2 LCD

[RasmusLauritsen]

There is a New Fireware out now did the Fysetec LCD problem fix it now with the New Firmware ? Did some tested ?

No change here with the Fysetc 3.2 LCD

It's the same for me. Still flashing the Fysetc 3.2 LCD.

[PhilippeGalid]

I'm not a programmer but my idea is perhaps if you know better and also have a clone, you can't compare the source code of the old firmware with the new one, what the frequency of the firmware is for the display and the new one with the old one Switching over and then creating a firmware file is just an idea. I would like to print faster but don't want to buy an original board and display for 150 euros. Maybe someone has an idea. Or an adapter between the cable and display fixes it with transistors,... there must be a solution, or Fysetc should find a solution.

[KR4DIO]

what the frequency of the firmware is for the display and the new one with the old one

I spent a little time looking through the source, but couldn't find where the SPI frequency was changed. However, as far as I can tell, the flashing doesn't actually affect printing. If I'm printing with the enclosure open and the flashing is annoying, I just go to Live Z Adjust mode, where the screen doesn't flash. It's not ideal, but at least for now the inconvenience is worth it for fast smooth prints.

[pchrist]

I finally got hold of a Fysetc display, I hooked up a logic analyzer to the SPI signals between the MCU and the display controller. I found out that a read command to the display is issued every 2 seconds (on the SDA line). On a Prusa display the response is seen on the SDO line. On the Fysetc display the response is seen on the SDA line.

It looks like the Prusa display is running in full duplex mode and the Fysetc display is running in half duplex mode. As long as nothing is read back from the display this does not matter. Since release 4.6.1 a LCD communication check is executed every 2 seconds. The check will fail when running half duplex mode, resulting in a display reset, seen as a white screen.

The half/full duplex configuration is done on the display by pulling some configuration pins high or low. These pins are not easily accessible on the Fysetc display.

[diminDDL]

@pchrist could you share what the pins are even if they aren't easily accessible? Unless they are not broken out to the flat flex altogether.

[CuriousTimo]

I'm looking at the st7789 datasheet and I think it has to do with IM3 pin.

SDA: -When IM3: Low, SPI interface input/output pin -When IM3: High, SPI interface input pin

So IM3 should be pulled high

[CuriousTimo]

I compiled and flashed version 5.1.0-alpha2

In file: src/gui/display_hw_checks_MINI.cpp I commented out line 21.

void check_lcd() {
    uint8_t data_buff[ST7789V_MAX_COMMAND_READ_LENGHT] = { 0x00 };
    display::ReadMADCTL(data_buff);

    if ((data_buff[1] != 0xE0 && data_buff[1] != 0xF0 && data_buff[1] != 0xF8)) {
        //reinit_lcd_and_redraw();
    }
}
} // anonymous namespace

My Fysetc 3.2" LCD is not flashing anymore.

The disadvantage is that you have to break out the tab on the Buddy board to run self-compiled firmware for this to work.

[PhilippeGalid]

Thanks for your Info and Help,I hope Pruse see this and fixe this in the next Update.

[Gabri988]

I compiled and flashed version 5.1.0-alpha2

In file: src/gui/display_hw_checks_MINI.cpp I commented out line 21.

void check_lcd() {
    uint8_t data_buff[ST7789V_MAX_COMMAND_READ_LENGHT] = { 0x00 };
    display::ReadMADCTL(data_buff);

    if ((data_buff[1] != 0xE0 && data_buff[1] != 0xF0 && data_buff[1] != 0xF8)) {
        //reinit_lcd_and_redraw();
    }
}
} // anonymous namespace

My Fysetc 3.2" LCD is not flashing anymore.

The disadvantage is that you have to break out the tab on the Buddy board to run self-compiled firmware for this to work.

would you be so kind as to post your modified fw? I have the same fystec LCD and would like to solve the flashing problem

[CuriousTimo]

Mini 5.1.0-alpha2-no_reinit_lcd.zip

To force a firmware update on the Mini:

• Push the reset-button, immediately followed by double-pressing the selector-knob.
• On the new screen, confirm the update by selecting the "FLASH" button and pressing the knob.

[Gabri988]

Mini 5.1.0-alpha2-no_reinit_lcd.zip

To force a firmware update on the Mini:

* Push the reset-button, immediately followed by double-pressing the selector-knob.

* On the new screen, confirm the update by selecting the "FLASH" button and pressing the knob.

A thousand thanks! Just installed on buddy clone board without needing to cut the jumper. it seems to work

[PhilippeGalid]

Mini 5.1.0-alpha2-no_reinit_lcd.zip To force a firmware update on the Mini:

* Push the reset-button, immediately followed by double-pressing the selector-knob.

* On the new screen, confirm the update by selecting the "FLASH" button and pressing the knob.

A thousand thanks! Just installed on buddy clone board without needing to cut the jumper. it seems to work

Thanks for your Work and Help

[PhilippeGalid]

Mini 5.1.0-alpha2-no_reinit_lcd.zip

To force a firmware update on the Mini:

* Push the reset-button, immediately followed by double-pressing the selector-knob.

* On the new screen, confirm the update by selecting the "FLASH" button and pressing the knob.

Thanke for your Work and Help

[diminDDL]

Can confirm that this fixes the flashes completely.

[hreality]

Cofirmed.. flashing resolved with posted firmware

[ZeekWorld]

Amazing work!

[Lino77]

press ignore

[Lino77]

@CuriousTimo The IM3 pin which is the one on the Fysetec display, I would like to use the 3.2 display, but I don't want to break the seal, it´s on original Mini.