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from . import Grove_ADC
__author__ = "Yun Rock Qu"
__copyright__ = "Copyright 2016, Xilinx"
__email__ = "pynq_support@xilinx.com"
def _int2r(val):
"""Convert the integer value to the light sensor resistance.
This method should only be used internally.
Note
----
A smaller returned value indicates a higher brightness. Resistance
value ranges from 5.0 (brightest) to 35.0 (darkest).
Parameters
----------
val : int
The raw data read from grove ADC.
Returns
-------
float
The light sensor resistance indicating the light intensity.
"""
if 0 < val <= 4095:
r_sensor = (4095.0 - val) * 10 / val
else:
raise RuntimeError("Value out of range or device not connected.")
return float("{0:.2f}".format(r_sensor))
[docs]class Grove_Light(Grove_ADC):
"""This class controls the grove light sensor.
This class inherits from the grove ADC class. To use this module, grove
ADC has to be used as a bridge. The light sensor incorporates a Light
Dependent Resistor (LDR) GL5528. Hardware version: v1.1.
Attributes
----------
microblaze : Pmod
Microblaze processor instance used by this module.
log_running : int
The state of the log (0: stopped, 1: started).
log_interval_ms : int
Time in milliseconds between sampled reads.
"""
def __init__(self, mb_info, gr_pin):
"""Return a new instance of an Grove ADC object.
Parameters
----------
mb_info : dict
A dictionary storing Microblaze information, such as the
IP name and the reset name.
gr_pin: list
A group of pins on pmod-grove adapter.
"""
super().__init__(mb_info, gr_pin)
[docs] def read(self):
"""Read the light sensor resistance in from the light sensor.
This method overrides the definition in grove ADC.
Returns
-------
float
The light reading in terms of the sensor resistance.
"""
val = super().read_raw()
return _int2r(val)
[docs] def start_log(self):
"""Start recording the light sensor resistance in a log.
This method will call the start_log_raw() in the parent class.
Returns
-------
None
"""
super().start_log_raw()
[docs] def get_log(self):
"""Return list of logged light sensor resistances.
Returns
-------
list
List of valid light sensor resistances.
"""
r_log = super().get_log_raw()
return [_int2r(i) for i in r_log]
[docs] def stop_log(self):
"""Stop recording light values in a log.
This method will call the stop_log_raw() in the parent class.
Returns
-------
None
"""
super().stop_log_raw()