MX8-DSI-OLED1A color problem

[nao_m]

Hi,

I'm using an imx8M Plus with MX8-DSI-OLED1A panel. When I checked a ramp test pattern, some colors at low level have problem as the attached picture. It looks the blue bits are missing at low level.

I also checked HDMI output if this symptom occurs, but it didn't. This symptom occurs only on MX8-DSI-OLED1A.
Does anyone know how to fix this issue? Thanks.

[Rita_Wang]

Which version BSP are you using? Are you using the NXP i.MX8MP reference board?

[YKL]

我使用的硬件是i.MX8qm（MX8-DSI-OLED1A），下载的是官方的android_13.0.0_1.2.0演示图像。

显示的图像颜色不正确，无法触摸。

请帮帮我，谢谢！

[nao_m]

Hi,

BSP version is LF_v5.10.72-2.2.0, and yes, I'm using the i.MX8MP reference board.

Thanks!

[Rita_Wang]

Are you using the demo images? Or images you build yourself?

[nao_m]

It's a PNG image file. First, I found the color issue on my application demo. So, I tested with the PNG ramp pattern without the demo to make the issue simple. Stored the attached image in a directory and set "background-image" in weston.ini to the PNG file.

[Rita_Wang]

How about running the demo images? Recommend you to use the demo images to have a test firstly, and share us the test result.

Wish you have a nice day

[nao_m]

Could you tell me where I can get the demo images and how to run them?

Thanks,

[Rita_Wang]

The linux demo images links https://www.nxp.com/design/software/embedded-software/i-mx-software/embedded-linux-for-i-mx-applicat...

Android demo images linkshttps://www.nxp.com/design/software/embedded-software/i-mx-software/android-os-for-i-mx-applications...

You can follow the related user guide document to download and boot up board.

Then to see if the screen can display well or not.

[nao_m]

I might misunderstood the meaning of "demo". Actually, I'm using the Linux image that I downloaded from the link you shared. The color issue occurred on the Linux image. I didn't build the Linux image myself.
And I used uuu to update the Linux image on the board, executed uuu.auto that is stored in the LF_v5.10.72-2.2.0_images_IMX8MPEVK.

Thanks,

[Rita_Wang]

Does the system boot up success? And have you set the proper parameters for the OLED display, you can show us you u-boot command line and boot up log file to us? We can help check.

If it still not work, the screen maybe broken, you can apply to change new one.

[nao_m]

In u-boot, I set the following command to use MX8-DSI-OLED1A

U-Boot > setenv fdtfile imx8mp-evk-rm67199.dtb
U-Boot > run bootcmd

System looks working well after boot up. An application I created is running on the screen, and touch screen works.

Please find the attached bootup log.

Thanks,

[nao_m]

Hello, Have you found anything wrong in the boot-up log?
And, I was wondering if this issue is only in this particular display I'm using or could be reproduced in your side?

Thanks,

[Rita_Wang]

You boot up is OK, no problem. I have tested on our board for this screen, it works well. I run the demo images.

Can you give us your details steps?

[nao_m]

Thank you for taking your time to test on your board. The below is my details steps.

• When I received a i.MX 8M Plus PEVK board, Linux Binary version "L5.4.70-2.3.2" was preinstalled in the board.
• I downloaded the latest version of Linux image "LF_v5.10.72-2.2.0" from the NXP website, and I updated the Linux image on the board by uuu. I ran uuu.auto that is stored in the LF_v5.10.72-2.2.0_images_IMX8MPEVK. (I executed the command uuu -d uuu.auto from Windows PowerShell.)
• Power on the board and edit /etc/xdg/weston.ini with adding the script below to remove menu-bar shown at the top of screen.

[shell]

panel-location=""

panel-position=none

• Reboot the board and interrupt auto-boot in the serial terminal. Change the device tree file by entering the commands below.

U-Boot > setenv fdtfile imx8mp-evk-rm67199.dtb

U-Boot > run bootcmd

I ran an application I created, then I found this color issue, some level of gray color was green. To make sure if the issue is caused by my application or not, I displayed a ramp test pattern image without running my application as following steps.

• Store ramp test pattern images under the root folder.(See attached files for testpatterns I used)
• Edit weston.ini with adding the script below.

[shell]

background-image=/home/root/ramp_pattern.jpg

• Reboot the board and change device tree to rm67199 in u-boot.
• The color issue occurs in the ramp image.(See attached files for the color issue on display)

Thanks,

[Rita_Wang]

I am not sure it is caused by your application, another way is to run the Android BSP demo images in our website, to see if the screen can display or not, if it display still, this will confirm that it caused by the broken screen. You can try it and give me the feedback.

[nao_m · Accepted solution]

Hello NXP TechSupport,

I purchased another display and confirmed this color issue was not occurred. It was a hardware issue.

Thank you so much for your support.

Thanks!

[Rita_Wang]

Good news it works well and thanks a lot for your kindly sharing.