Class: BH1750

Inherits:
Object
  • Object
show all
Defined in:
lib/bh1750.rb

Overview

BH1750 - ambient light sensor

Constant Summary collapse

DEVICE =

I2C sensor address

0x23
POWER_DOWN =

off state

0x00
POWER_ON =

on state

0x01
RESET =

reset state: POWER_DOWN = 0x00

0x07
CONTINUOUS_LOW_RES_MODE =

Measure with resolution 4.0 lx and timing ~16 ms

0x13
CONTINUOUS_HIGH_RES_MODE_1 =

Measure with resolution 1.0 lx and timing ~120 ms

0x10
CONTINUOUS_HIGH_RES_MODE_2 =

Measure with resolution 0.5 lx and timing ~120 ms

0x11
ONE_TIME_LOW_RES_MODE =

Measure with resolution 4.0 lx, POWER DOWN after measuring

0x23
ONE_TIME_HIGH_RES_MODE_1 =

Measure with resolution 1.0 lx, POWER DOWN after measuring

0x20
ONE_TIME_HIGH_RES_MODE_2 =

Measure with resolution 0.5 lx, POWER DOWN after measuring

0x21

Instance Method Summary collapse

Constructor Details

#initialize(i2c_bus = '/dev/i2c-1') ⇒ BH1750

Returns a new instance of BH1750.



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# File 'lib/bh1750.rb', line 17

def initialize(i2c_bus='/dev/i2c-1')
  @sensor_name = 'BH1750'
  @i2c_bus = i2c_bus
  @device = I2CDevice.new(address: DEVICE, driver: I2CDevice::Driver::I2CDev.new(@i2c_bus))
  @resolution = ONE_TIME_HIGH_RES_MODE_1
  @length = 2
  @value = read_sensor
end

Instance Method Details

#lux ⇒ Object

Return value in Lux



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# File 'lib/bh1750.rb', line 33

def lux
  read_sensor
  @value
end

#read_sensor ⇒ Object

Read raw data from sensor and convert it to numeric



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# File 'lib/bh1750.rb', line 27

def read_sensor
  data = @device.i2cget(@resolution, @length)
  @value = to_f(data)
end