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