from .adc_base import ADCBase
[docs]class LightSensor(ADCBase):
"""Encapsulates the behaviour of a light sensor module.
A simple analogue photo transistor is used to detect the intensity of the light striking
the sensor. The component contains a photoresistor which detects light intensity. The
resistance decreases as light intensity increases; thus the brighter the light, the
higher the voltage.
Uses an Analog-to-Digital Converter (ADC) to turn the analog reading from the sensor
into a digital value.
By default, the sensor uses 3 samples to report a :attr:`~.LightSensor.reading`, which takes around 0.5s.
This can be changed by modifying the parameter :attr:`~.LightSensor.number_of_samples` in the constructor.
:param str port_name: The ID for the port to which this component is connected
:param str number_of_samples: Amount of sensor samples used to report a :attr:`~.LightSensor.reading`. Defaults to 3.
:param str name: Component name, defaults to `light_sensor`. Used to access this component when added to a :class:`pitop.Pitop` object.
"""
def __init__(
self, port_name, pin_number=1, name="light_sensor", number_of_samples=3
):
ADCBase.__init__(
self,
port_name=port_name,
pin_number=pin_number,
name=name,
number_of_samples=number_of_samples,
)
@property
def reading(self):
"""Take a reading from the sensor.
:return: A value representing the amount of light striking the sensor at the current time
from 0 to 999.
:rtype: float
"""
return int(self.read())
@property
def value(self):
"""Get a simple binary value based on a reading from the device.
:return: 1 if the sensor is detecting any light, 0 otherwise
:rtype: integer
"""
if self.reading > 0:
return 1
else:
return 0
@property
def own_state(self):
return {
"value": lambda: self.value,
"reading": lambda: self.reading,
}