ut does this reflect the square waves of PWM output?
Yes.
will I need the external 16MHz clock to influence this to be 16 times faster and after that it will become unnoticeable?
Again yes
ut does this reflect the square waves of PWM output?
Yes.
will I need the external 16MHz clock to influence this to be 16 times faster and after that it will become unnoticeable?
Again yes