Eric W. Biederman wrote:
> > What does exist is the bus clock (well, a multiple of it, but you get the
> > idea), and that one is stable. I bet PCI devices don't like to be randomly
> > driven at frequencies "somewhere between 12 and 33MHz" depending on load ;)
>
> I doubt they would like it but it is perfectly legal (PCI spec..) to
> vary the pci clock, depending upon load.
Yes it is. Also, the PCI clock is frequency modulated to reduce
electrical interference. (Or on a more cynical note, to pass the
official emissions tests ;-)
However it's common practice to PLL to the PCI clock, for clock
distribution on a board, so varying the frequency must be done in a
strictly constrained fashion.
-- Jamie
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This archive was generated by hypermail 2b29 : Sun Sep 30 2001 - 21:01:06 EST