def read(self):
"""Get the output brightness of the LED.
Returns:
int
"""
return int(utils.readstr_all(_LED_FILE(self._name, 'brightness')))
def max_brightness(self):
"""Maximum brightness value supportd by the LED.
Returns:
int
"""
return int(utils.readstr_all(_LED_FILE(self._name, 'max_brightness')))
def name(self):
"""Linux name of the ADC device.
:type: str
"""
return utils.readstr_all(
os.path.join(_DEVICE_PATH(self._device), 'name'))
def enabled(self):
"""Enabled property of the PWM.
:type: bool
"""
return bool(int(utils.readstr_all(os.path.join(_CHANNEL_PATH(self._chip,
self._channel),
'enable'))))
def period(self):
"""Microsecond period of the PWM.
:type: int
"""
period_ns = int(utils.readstr_all(os.path.join(_CHANNEL_PATH(self._chip,
self._channel),
'period')))
return int(period_ns / 1000)
def sampling_frequency(self):
"""Get the sampling frequency of the ADC.
:type: int
"""
return int(
utils.readstr_all(
os.path.join(_DEVICE_PATH(self._device),
'sampling_frequency')))
def num_channels(chip):
"""Get the number of available PWM channels on the specified chip.
Args:
chip (int): The PWM chip id.
Returns:
int
"""
return int(utils.readstr_all(os.path.join(_CHIP_PATH(chip), "npwm")))
def duty_cycle(self):
"""Duty cycle of the PWM.
:type: float
"""
duty_cycle_ns = int(utils.readstr_all(os.path.join(_CHANNEL_PATH(self._chip,
self._channel),
'duty_cycle')))
if self.period > 0:
return float(duty_cycle_ns / 1000.0 / float(self.period))
else:
return 0.0
def polarity(self):
"""Polarity setting of the PWM.
Basically, this sets the "active high" or "active low" setting of the
PWM.
:type: PWM.NORMAL, PWM.INVERSED
Note:
This a readonly property because we set polarity in creation and
there seems to be little value in changing it later.
"""
return utils.readstr_all(
os.path.join(_CHANNEL_PATH(self._chip, self._channel), "polarity"))
def scale(self):
"""Get the ADC value scale.
The value you have to multiply the ADC value by to get microvolts.
:type: float, None
"""
if not os.path.isfile(
os.path.join(_DEVICE_PATH(self._device), 'in_voltage_scale')):
return None
return float(
utils.readstr_all(
os.path.join(_DEVICE_PATH(self._device), 'in_voltage_scale')))
def available_triggers(self):
"""List of available trigger names for the device.
One of the names returned here can then be used when calling
``start_capture()`` to specify the trigger.
:type: list: A list of trigger names available.
"""
names = []
triggers = [f for f in os.listdir(_ADC_ROOT) if \
os.path.isdir(os.path.join(_ADC_ROOT, f)) and 'trigger' in f]
for trigger in triggers:
names.append(
utils.readstr_all(os.path.join(_ADC_ROOT, trigger, 'name')))
return sorted(names)
def value(self, channel):
"""
Perform a software trigger and get the raw ADC value.
Calling this function causes a software trigger of the ADC. The ADC
will do a conversion and then return the value.
Args:
channel (int): The ADC channel.
Returns:
int
"""
if not isinstance(channel, (int)):
raise TypeError("channel must be an int.")
return int(
utils.readstr_all(
os.path.join(_VOLTAGE_RAW_PATH(self._device, channel))))
