minix/drivers/tsl2550/README.txt

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TSL2550 Driver (Ambient Light Sensor)
=====================================
Overview
--------
This is the driver for the ambient light sensor commonly found on the
WeatherCape expansion board for the BeagleBone.
Interface
---------
This driver implements the character device interface. It supports reading
through /dev/tsl2550b{1,3}s39. When read from, it returns a string containing
a data label, a colon, and the sensor value.
Example output of `cat /dev/tsl2550b3s39`:
ILLUMINANCE : 830
Illuminance is expressed in lux. Valid values are 0 to 1846.
Limitations
-----------
Extended mode isn't implemented. Normal mode should be sufficient for most
applications.
Testing the Code
----------------
The driver should have been started by a script in /etc/rc.capes/ If not,
this is how you start up an instance:
cd /dev && MAKEDEV tsl2550b3s39
/bin/service up /usr/sbin/tsl2550 -label tsl2550.3.39 -dev /dev/tsl2550b3s39 \
-args 'bus=3 address=0x39'
Getting the sensor value:
cat /dev/tsl2550b3s39
Killing an instance:
/bin/service down tsl2550.3.39