CoreInk display fades

desmbr · Feb 28, 2025, 6:19 PM

Hi, I'm trying to solve fading display color. After a few cycles of light sleep CoreInk dispay becomes pale. I found a post with solution for UiFlow ver.1 https://community.m5stack.com/topic/3158/core-ink-screen-fades-on-reset

How can I achieve the same with UiFlow2? Is there a "Set Screen HV" block? Or what is the equivalent in python?

Thanks.

ajb2k3 · Feb 28, 2025, 6:19 PM

@desmbr If you want data to remain visible after shutdown or sleep, you do as you have surmised have to trigger the Screen HV, write the data then shut down.
The fading without the set screen HV is normal.

desmbr · Mar 2, 2025, 10:05 AM

Hi @ajb2k3 ,
That is what I'm asking :) I don't see which widget/code can do so. Can you show an example please?

Btw, what does HV stand for?

desmbr

Sorry for bumping the topic, but I would really appreciate any kind of advice. I suppose missing Set screen HV block in UIFlow2.0 is a gap and is probably planned in a future release?

Is there an equivalent in python code for that?

felmue

Hello @desmbr

I created an UIFlow2 light sleep example for M5CoreInk but I cannot confirm the display fading you are reporting.

You can find my example in the UIFlow2 ProjectZone called: M5CoreInk_LightSleep_Test_UIFlow2.2.3

Thanks
Felix

desmbr

This post is deleted!

desmbr

There is something wrong with my device then.. This is what I see with your example project:

felmue

Hello @desmbr

hmm, yes, that doesn't look good.

Have you tried without the hat connected?

Have you tried when running from battery?

Have you tried to fully power off / on M5CoreInk? E.g.

disconnect USB-C
press and hold RST button in the back for 5 seconds
turn back on via side button (or by plugging in USB-C)

Also, are you running the latest UIFlow2 v2.2.3 firmware? Maybe use M5Burner to fully erase first and then reinstall UIFlow2 v2.2.3?

Thanks
Felix

desmbr

Hi @felmue ,

I disconnected everything. Updated UiFlow to 2.2.3.
After complete reset I see Ui logo, then for a second I see startup menu and then screen blinks and everything disappears.

felmue

Hello @desmbr

have you checked the boot option? In M5Burner click onto the Configure (yellow) button and then set Boot Option to Show startup menu and network setup. Then click onto Next to set the new boot option.

Thanks
Felix

desmbr

@felmue said in CoreInk display fades:

Hello @desmbr

have you checked the boot option? In M5Burner click onto the Configure (yellow) button and then set Boot Option to Show startup menu and network setup. Then click onto Next to set the new boot option.

Thanks
Felix

As I mentioned before, I tried that. The screen flashes a few times and then it is blank and I only see a vertical line on the right. If you look closer there are slightly whiter traces of UI

This is how it behaves: https://youtube.com/shorts/s7ljTruGtDk

And this is what remains:

felmue

Hello @desmbr

indeed, that doesn't look good. I wonder if maybe the internal battery is defective preventing the power rails from reaching the proper voltages.

Edit: first, however I would unplug the hat and maybe try a different USB power supply.

If you still have warranty, I suggest you ask for a replacement.

If not, you might try to open it and disconnect the battery to see if that helps. These pictures I took a while ago might be helpful opening M5CoreInk.

Thanks
Felix