Laptop Battery monitor

amjith · 10-02-2004, 02:49 AM

Is there is a way to find out the battery charge in Yoper?

psisquare · 10-02-2004, 07:06 AM

your kernel has to support ACPI for this to work. try
$ cat /proc/acpi/battery/BAT0/state
to find out.
if that works, you can use one of those nifty battery status monitors for your preferred desktop (i use wmacpi with Window Maker).

amjith · 10-02-2004, 11:10 AM

/proc/acpi is there, but there is no battery/BAT0/state inside the acpi. How do I make my kernel support acpi. Do I have to recompile it? If so with what options and can you point me to a thread where kernel recompiling is discussed?
Thanks

psisquare · 10-02-2004, 12:46 PM

i suggest you try loading the battery kernel module first:
# modprobe battery
if that helps, you can auto-load it on boot by adding a line reading "battery" to /etc/modules.

if it doesn't, you need to recompile the kernel. there's a kernel compilation tutorial on this site.
The Linux Documentation Project also maintains a Kernel-HOWTO, but it seems to be offline right now.

When configuring the kernel, you'll find the battery support under Power Management/ACPI/battery

amjith · 10-02-2004, 03:04 PM

Hi,
Thanks a lot. That helped. I did a modprobe battery and checked to see if there are any errors by using dmesg. I found no errors and I could find the state by doing a less /proc/acpi/battery/C152/state.

mightypile · 10-06-2004, 03:14 PM

Thanks psisquare!

I'd been wondering the same thing, followed your advice, and bingo, I'm off and running.