pinkish frame about the epaper screen

[d3kzar4]

Hello.
A question about the library GxEPD2 from Author ZinggJM.
I use a Waveshare e-paper 2.13inch HAT (B) experimentally with an Arduino Nano.
In the GxEPD2 library I select the right 3color display.

The problem or the blemish that i have is a pinkish frame around the edge of the display.
(i would like to add a photo, but i'm afraid of being banished again)

If i use the library from the manufactor Waveshare the pinkish frame disappear.
But i want to use the GxEPD2 library, there is a lot advantages.

Does anyone know how to prevent the pinkish frame?

Thanks a lot

[ZinggJM]

@d3kzar4,

Hello, welcome to the forum. If you haven't done yet, please read How to get the best out of this forum (short version).

Here in the display section, in addition we very much like you to post clickable links to the devices in question.
e.g. 212x104, 2.13inch E-Ink display HAT for Raspberry Pi, three-color.

Thank you for pointing me to this issue. The display driver code for most panels is derived from demo code from Good Display. And some of the code is already quite old. The Waveshare code may be newer.
Maybe it is just the selection of the border waveform that is different. You could take a look at the display initialization code. Or hope and wait for an improvement in a later version of GxEPD2 (not the one that is pending to be released), if I remember your post.

Readers of my topic Waveshare e-paper displays with SPI know that I don't really like 3-color displays.

BTW: if you want to attach photos, you can reduce the resolution, e.g. to 20%, e.g. with MS Paint and save as jpg.

Jean-Marc

The reason may be a change in the panel provided. GxEPD2_213c was done for GDEW0213Z16.
The actual panel may be GDEH0213Z19.

[d3kzar4]

@ZinggJM
Thank you for taking care of my concerns.

Here in the display section, in addition we very much like you to post clickable links to the devices in question.

I did that, I was banned and my account was lost.....that wasn't a good feeling.

I think I don't like 3color version too. The costs were very cheap, just right to experiment.

Although you understood my problem, I would like to add the photo

Maybe it is just the selection of the border waveform that is different. You could take a look at the display initialization code.

Could you please explain which library file I need to look into?

[ZinggJM]

@d3kzar4,

you could try to change line 364 of file GxEPD2_213c.cpp in src/epd3c:

from

  _writeCommand(0X50);
  _writeData(0x37); //VCOM AND DATA INTERVAL SETTING

to

  _writeCommand(0X50);
  _writeData(0x77); //VCOM AND DATA INTERVAL SETTING

this is different from the older demo source to the actual one:

    EPD_W21_WriteCMD(0X50);     //VCOM AND DATA INTERVAL SETTING      
    EPD_W21_WriteDATA(0x77);    //WBmode:VBDF 17|D7 VBDW 97 VBDB 57   WBRmode:VBDF F7 VBDW 77 VBDB 37  VBDR B7

The change makes no difference on my display. It has the same narrow light pink border in both cases, also around the round connection dot. I don't know if this is the border that should be controllable by some bits of this command.

Please report if this has the desired effect on your display.

Jean-Marc

[d3kzar4]

@ZinggJM

It works ..... I changed it so

...here to:

void GxEPD2_213c::_InitDisplay()
{
 ...
 ...  
 _writeData(0x77); //VCOM AND DATA INTERVAL SETTING
 ...
 ...
  }

...and here to:

void GxEPD2_213c::_Init_Part()
{
  ...
  ...
  _writeData(0x77);    //WBmode:VBDF 17|D7 VBDW 97 VBDB 57   WBRmode:VBDF F7 VBDW 77 VBDB 37  VBDR B7
  ...
}

the display looks much better now

Thank you man!

[ZinggJM]

@d3kzar4,

thank you for the feedback!

I will add this change to the next release, to work with the new panel version.

Jean-Marc