Beaglebone Black meta-ti + (LCD 7'' cape)

Hi,

I build an image for a beaglebone black using the yocto + meta-ti (3.14). My main idea is to output on an 7’’ LCD cape.

From now only the HDMI output is working. I test different resolution by changing some setting in the uEnv.txt and it work like a charm :slight_smile:

Back to the LCD, to get it working I tried several thing :

  1. I compiled this dts file (https://github.com/RobertCNelson/dtb-rebuilder/blob/3.14-ti/src/arm/am335x-bone-4dcape-70t.dts) to a dtb (with the dtb-rebuilder), copy it to the boot folder and
    adding “dtb=am335x-bone-4dcape-70t.dtb” to the uEnv.txt. I plug the LCD, unplung the HDMI and then put power on the BB. LCD still not working :frowning:

  2. Keeping the BB on power, I then tried pluging the HDMI also and now I get something on the LCD ?!? If I unplug the HDMI, LCD turns off. What is that ?

  3. Robert Nelson advise me to set the kernel backlight setting to yes. CONFIG_BACKLIGHT_GPIO=y The only problem is that I’m not able to do that using Yocto :frowning:

I’m curious, is the LCD supposed to work while having the right dtb file or I also need to applied change to kernel configuration ?

Best regards,