\> I am using a pic18F4553 in a project and I am having problems with
> the oscillator.
>
> I am trying to use the internal 8MHz clock PLL, prescaler etc (which
> works nicely clocking at 32MHz), but when it comes to working with the
> USB I am failing miserably.
>
> All of the Microchip documentation seems to contradict itself in
> each section when discussing the USB clock.
>
> My question is this:-
>
> Can i use the 8MHz internal oscillator to drive the 48MHz/6MHz
> needed for the on-chip USB peripheral, and if so, what settings would
> you use?

I would not try to use the internal clock to do USB, even if it is possible=
=20
on the chip (and I don't know if it is).

USB requires better clock accuracy than you are likely to get without a=20
resonator or crystal.

-- Bob Ammerman
RAm Systems

--=20
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