Rockbox mail archiveSubject: Re: Battery patch
Re: Battery patch
From: Mike Holden <rockbox_at_mikeholden.uklinux.net>
Date: Sun, 27 Apr 2003 17:10:07 +0100 (BST)
William Pietri said:
> On Sun, 2003-04-27 at 03:29, Mike Holden wrote:
>> > Having looked at the different styles to present battery level and
>> charging state, I think a steady battery symbol (or, upon config
>> option, a number) plus a flashing charger plug is the most
>> informative since the actual battery level is a good indicator of
>> the progress of the charging process.
>> I suggested this the other day, but the response was that this was
>> decided against, because when the charge shows 100%, the battery is
>> not actually fully charged, and still needs some more time. Apparently
>> people were removing the charger before the unit was fully charged.
> Perhaps this is a naive question, as I'm still pretty ignorant of both
> the code and the hardware. But given that the charger knows when to
> stop, couldn't you scale that 100% figure based on whatever metric the
> charger uses? So that the number when unplugged is always >= the number
> it shows when charging is underway?
My understanding (see the battery FAQ on the website for more info) is
that the charger keeps going until it measures a slight drop in the
voltage (due to heat build up in the battery). Until it gets this, it has
no indication that the battery is almost full, it only knows when it _is_
I have an FM unit, which works differently (hardware charging, which
Rockbox doesn't control), so I must confess I have not studied te
algorithm in any depth.
-- Mike HoldenReceived on 2003-04-27