class PWMOut(object):
"""PWM output."""
def __init__(self, pin, freq=50, duty=0, verbose=False, channel=-1):
if channel in [i for i in range(RMT_MAX_CHAN)]:
self._chanRMT = channel
self._pin = RMT(channel, pin=Pin(pin), clock_div=RMT_CLOCK_DIV)
self.__setRMTDuty(duty)
self._pin.loop(True)
else:
self._chanRMT = -1
self._pin = PWM(Pin(pin))
self._pin.init(freq=freq, duty=duty)
self._verbose = verbose
if self._verbose:
self.__logFrequency()
def deinit(self):
self._pin.deinit()
@property
def duty_percent(self):
""" duty in percent
"""
if self._chanRMT < 0:
return self._pin.duty() / MAX_DUTY * 100
else:
return self._dutyRMT / RMT_DUTY_SCALER
@duty_percent.setter
def duty_percent(self, value):
if self._chanRMT < 0:
self._pin.duty(int(min(max(0, value / 100.0 * MAX_DUTY),
MAX_DUTY)))
else:
self.__setRMTDuty(
min(max(0, value / 100. * RMT_MAX_DUTY), RMT_MAX_DUTY))
@property
def duty(self):
""" duty as raw value
"""
if self._chanRMT < 0:
return self._pin.duty()
else:
return self._dutyRMT
@duty.setter
def duty(self, value):
if self._chanRMT < 0:
self._pin.duty(int(value))
else:
self.__setRMTDuty(value)
@property
def freq_Hz(self):
""" frequency in [Hz]
"""
if self._chanRMT < 0:
return self._pin.freq()
else:
return self._pin.source_freq() / RMT_CLOCK_DIV
@freq_Hz.setter
def freq_Hz(self, value):
if self._chanRMT < 0:
self._pin.freq(value)
else:
if value == 0:
self._pin.loop(False)
else:
self._pin.loop(True)
d2 = int(
(self._pin.source_freq() / RMT_CLOCK_DIV) / value // 2)
self._pin.write_pulses((d2, d2))
if self._verbose:
self.__logFrequency()
@property
def max_duty(self):
if self._chanRMT < 0:
return MAX_DUTY
else:
return RMT_MAX_DUTY
@property
def uses_rmt(self):
return self._chanRMT >= 0
def __logFrequency(self):
print("PWM frequency is {0:.1f} kHz".format(self.freq_Hz / 1000))
def __setRMTDuty(self, value):
self._dutyRMT = int(min(max(1, value), RMT_MAX_DUTY))
self._pin.write_pulses((self._dutyRMT, RMT_MAX_DUTY - self._dutyRMT))
