cvs commit: src/sys/kern subr_param.c

Paul Richards paul at originative.co.uk
Mon Nov 8 18:50:48 GMT 2004


On Sat, Nov 06, 2004 at 04:03:12PM -0800, Kris Kennaway wrote:
> On Sat, Nov 06, 2004 at 03:50:06PM -0800, Nate Lawson wrote:
> 
> > I was traveling out of the country so I didn't get a chance to comment. 
> >  The two caveats I'm aware of is a slight loss in processes that are 
> > CPU bound and an audio hum from ACPI CPU idling.  The latter is rather 
> > interesting actually.  At hz=100, it's just a quiet low buzz but at 
> > 1000, it is readily audible on many laptops and annoying.  Windows uses 
> > hz=1000 too and has the same problem.  I believe it's related to the 
> > capacitors and other devices charging/discharging when clocks are stopped.
> 
> Can we play music by modulating the value of hz? :)

I remember some code for the Commodore Pets that you could use to play
notes on a nearby radio by tweaking some spinning loops. Quite a neat
trick at the time since there wasn't any sound hardware.

Paul.


More information about the cvs-src mailing list