Messages in this thread | | | Subject | Re: [POWER] battery calibration parameters from sysfs | From | Stanislav Brabec <> | Date | Wed, 16 Dec 2009 00:32:18 +0100 |
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Aras Vaichas wrote:
> 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)
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.
- We know the time. - We know the backlight power consumption, it's dependent only on brightness. - We know how much eats the HDD and how long it is on. - We know how much eats the CPU and companion chips (it is not as stable, but it eats less). - We don't know, how much USB host eats, but we know how much USB clients claim to eat. - Well, and we don't know how much eats CF and SD.
=> We can guess how many Coulombs the device already consumed. If the Coulomb counting would be inaccurate, we can at least correct voltage -> remaining energy table using current power consumption guess.
________________________________________________________________________ Stanislav Brabec http://www.penguin.cz/~utx/zaurus
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