N900 light meter

(Software: meego)
(Hardware: TAOS->AMS)
Line 3: Line 3:
The device is a TAOS [http://www.taosinc.com/downloaddetail.aspx?did=141 TSL2563].
The device is a TAOS [http://www.taosinc.com/downloaddetail.aspx?did=141 TSL2563], now AMS [http://www.ams.com/eng/content/download/250126/975581/TSL2563_Datasheet_EN_v1.pdf TSL2563]

Revision as of 14:24, 20 October 2014

The light meter lets the software on the N900 sense ambient light levels.


The device is a TAOS TSL2563, now AMS TSL2563


It is handled by the kernel module tsl2563.

The kernel driver exposes the lux value in the sysfs file

cat /sys/class/i2c-adapter/i2c-2/2-0029/lux

Under MeeGo it's available as

cat /sys/class/i2c-adapter/i2c-2/2-0029/device0/illuminance0_input

Note: please check! This might only be one of the two different spectral channels and thus yield vastly incorrect LUX values when massive IR or UV light has impact on the sensor. The lux value of N900 is generic and derived from an algorithm calculating visible lux from roughly a difference between the two sensor values the ALS provides

Third party applications that use this sensor include Luxus Light Meter and photographic light meter.

The sensor is also used to modulate the backlight in response to ambient light, although this behaviour can be disabled.