What is rc_check_battery reporting?

I’ve got my beaglebone black powered by usb and also connected to a wired ethernet but there is no battery anywhere in sight. When I run rc_check_battery it reports changing values

Pack: 18.79V Cell: 9.40V DC Jack: 18.65V

Is the USB cable supplying 18 volt power? What is it reporting.

I am just curious. Nothing seems to be wrong.


Are you using the BBBlue or the BBB? I think the file rc_check_battery was for the DTS files directed at the BBBlue. So, in this idea, I think there would be some odd reporting in output. It is not reporting correctly obviously. I think maybe, if using the BBB w/ Robotics Cape, there may be some slight differences in output.

Have you seen the DTS files, dtsi files, and moved to using the Robotics Cape specific dtbo file?

@cre , I have not heard of USB connections from the host allowing for 18.x+ volts. That would be odd for the board in question and probably would disable it.


Sort of an update here…

Just thinking here and accuse me or call me out if I am over-the-line…

I think w/ u-boot, thekernel`, and installed image, there is a lot going on that may be hard to track down…

For instance, would you give out some info? I personally would like the output of the commands listed:

cat /etc/dogtag
uname -a

cat /boot/uEnv.txt

Are there changes made to the lib. that you have made yourself, e.g. in the files listed that may counteract its use?

This could be a reason or another reason I see just from guessing so far would be the .dtb file used if used in the /boot/uEnv.txt file. Maybe the .dtb file, if needed or not needed, is there or not. Either/or/if/not, tracking down older lib. errors that are not used much or updated for recent distros and images causes this oddity.

So, I saw in u-boot a while back, some changes to the way the boards interrupted DTS files (.dtb, .dtsi, .dtbo).

Also, the kernel has been updated and is for now, the kernel (depending on what kernel is being used).

Updates and finding the window of use sometimes comes and goes but…

If it works, do not break it (most of the time)…

I like trying to get the BBBlue up and running still for learnin’ about u-boot changes, kernel ideas, and programming. That board has been the most dramatic learning experience so far for me. Anyway, if you need more ideas on specifics, I can try to get more technical.