Re: Low battery -> power down + clock set back to 1904-01-01
On 23 Jan, this message from Michael Schmitz echoed through cyberspace:
> 1) battery capacity tends to decrease over time. To see how much
> capacity is left, run without pmud (or similar service), remount
> everything ro and wait for it to power off.
Here is some anectdotical information about my dying battery, just to
show what _can_ happen:
My max_charge (from /proc/pmy/battery_0) is down to 465; but was down to
225 already before (from an original, brand-new value of between 3000
and 4000).
My battery will last, according to its controller, some 30 minutes only.
But voltage will still be above 14.0 when 0 charge is indicated.
I therefore deactivate pmud, so I don't get the automatic sleep or
shutdown happening after the 30 minutes. Anyway, the battery charge will
go in a matter of a mnute from 20% to empty.... leaving no time to react
after the initial warning.
That way, I can run for maybe 2 hours (depending on useage and backlight
level) before the battery voltage gets too low. The battery controller
actually goes on providing power until the battery voltage drops to
12.5V, which is the end-of-discharge voltage of Li-ion batteries as used
in this Powerbook.
It would be interesting for pmud to be able to work on battery voltage
instead of the time left as indicated by the obviously mislead battery
controller...
Cheers
Michel
-------------------------------------------------------------------------
Michel Lanners | " Read Philosophy. Study Art.
23, Rue Paul Henkes | Ask Questions. Make Mistakes.
L-1710 Luxembourg |
email mlan@cpu.lu |
http://www.cpu.lu/~mlan | Learn Always. "
Reply to: