This driver has the MicroPython-ism of a setter/getter function where its a getter when values are None and setter when they are not. This is not Pythonic and confusing.

Instead, this API should be changed so that it has a number of channels that act like pulseio.PWMOut with frequency and duty_cycle as properties. frequency of each channel would be read only because its shared amongst all channels. The outer class can have an adjustable frequency property.