Editing N900 Hardware Charge Meter

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There is no kernel driver in the default N900 software for this chip, a [http://tomoyo.sourceforge.jp/cgi-bin/lxr/source/drivers/power/bq27x00_battery.c partial third party driver bq27x00_battery exists].
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There is no kernel driver in the default N900 software for this chip, a [http://tomoyo.sourceforge.jp/cgi-bin/lxr/source/drivers/power/bq27x00_battery.c partial third party driver exists].
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This third party driver has some issues - for example - the 'current_now' value it exports is not mA, but needs multiplied by (3.57/n) - where n is the sense resistor in the N900. The sense resistor seems to be between 20 and 22 mR - but no accurate measurements have been performed, and the schematic does not help with this.
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This third party driver has some issues - for example - the 'current_now' value it exports is not mA, but needs multiplied by (3.57/n) - where n is the sense resistor in the N900.
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Now on kernel mailinglist is series of patches which improve (report more properties about battery then BME) kernel driver bq27x00_battery. All these issues are fixed. Backported patches for N900 are here: http://talk.maemo.org/showpost.php?p=925980&postcount=674
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The sense resistor seems to be between 20 and 22 mR - but no accurate measurements have been performed, and the schematic does not help with this.

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