pin.set_analog_period(0) stops PWM output from working again #141
Description
To replicate, in the REPL while watching pin16 in an oscilloscope or signal analyser:
>>> pin16.write_analog(512) # signal appears at 50 Hz
>>> pin16.set_analog_period(1) # signal at 1 KHz
>>> pin16.set_analog_period_microseconds(1) # signal at 1 MhHz
>>> pin16.set_analog_period_microseconds(0) # signal always high
>>> pin16.set_analog_period(1) # signal still always highI'll try to replicate with CODAL as well and raise an issue there if necessary.