[POWER] battery calibration parameters from sysfs

[pavel@ucw.cz (Pavel Machek)]

Hi!1


>>> Yes, but in that case you might as well just purchase a coulomb
>>> counter with a built-in accumulator and an I2C/SPI/microwire interface
>>> save yourself some PCB space and cost (maybe)

Hardware is already given.

>> Well, Pavel attempts to implement a "poor man's Coulomb counter" or at
>> least "poor man's Ampere meter" for devices that are not equipped with
>> any of it.
>
> I think the "poor man's Coulomb counter" is a loser, the errors will  
> overwhelm you too rapidly.  The estimated rate of discharge could
>> work,  

Actually android phones do "poor man's Coulomb counter", and it seems
to mostly work.

> based on what clocks, regulators and so on are running, but I am not  
> sure how useful that number is really given you can't realistically  
> integrate it due to the big error it is bound to have.
...
> Otherwise for L-ion batteries, looking at the voltage level alone,  
> filtered to remove GSM transmit slots etc, is really quite workable for  
> estimating charge status.

Well, you have to compensate for backlight power; and yes, that's what
I'm trying to do.
								Pavel 

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