Which .dtb file does the beagle bone black use?

I am trying to figure out which .dtb file my current version of u-boot is using on my beaglebone black so that I can make edits to it, whenever I edit the am335x-boneblack.dtb my changes have no effect on reboot. If someone could point me to which file my board is using or how to find it I would be very grateful, so far my attempts at finding which file u-boot uses have been unsuccessful.

I’m new to Linux, but I believe the /boot/uEnv.txt file has the list of .dtb files that are currently in use. I modified this file to turn off HDMI and turn on the universal cape so I can use all the encoders, and it worked.

Hi @jamianv , it’s complicated when enable_uboot_overlays=1 is set in /boot/uEnv.txt…

https://elinux.org/Beagleboard:BeagleBoneBlack_Debian#U-Boot_.2Fboot.2FuEnv.txt_configuration

As we generate the final *.dtb in few steps in u-boot…

Thus if you disable enable_uboot_overlays=1 it’ll just be… am335x-boneblack.dtb

Regards,

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I see, thank you very much @RobertCNelson that makes a lot of sense. I was able to figure out how to do what I needed using the file am335x-boneblack-uboot-univ.dtb, but given this information I may do something different. If I disable enable_uboot_overlays=1 I won’t be able to use any overlays at all correct?

It’s your choice, nuking enable_uboot_overlays=1 means you need to do everything in am335x-boneblack.dtb, and u-boot won’t try to do any overlays…

Also if you disable: enable_uboot_cape_universal=1 then the file is: am335x-boneblack-uboot.dtb vs “*uboot-univ.dtb”

Regards,