c58da9fbc3
IMPORTANT: this change has a docs/UPDATING entry! This rename is unfortunately necessary because NetBSD has decided to create its own service(8) utility, and we will want to import theirs as well. The two can obviously not coexist. Also move ours from /bin to /sbin, as it is a superuser-only utility. Change-Id: Ic6e46ffb3a84b4747d2fdcb0d74e62dbea065039
47 lines
1.1 KiB
Plaintext
47 lines
1.1 KiB
Plaintext
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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/sbin/minix-service up /service/tsl2550 -label tsl2550.3.39 \
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-dev /dev/tsl2550b3s39 -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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/sbin/minix-service down tsl2550.3.39
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