On Sun, Feb 08, 2004 at 07:55:27PM +0100, Andreas Mueller wrote:
> Gerrit wrote:
> > Alberto Molteni wrote:
> > > When I try to halt the machine I see all the apps
....
> > > Flushing ide devices: hda hdb
> > > Power down.
> > >
> > > or something like that. And then the computer hangs,
....
> > You need to configure APM, Advanced Power Management, but some
> > hardware is unable to do that.
>
> If this doesn't work, try booting the kernel with "acpi=on" for ACPI
> support.
I have recently learned a bit about ACPI, the new way to fiddle with
hardware.
Intel has been a good guy on this. They have published tools both for
Linux and Windows that include source and reference ports. Surf over
there and find a lot of on line data.
In part ACPI picks up bits and interacts with the BIOS to interpret.
Underneath it all there is a ACPI interpreter.
Most current BIOS setup tools permit ACPI to be disabled, so does
Linux. With 2.4.xxx kernels ACPI is compiled in.
This gives a couple of permutations:
BIOS ACPI On/ Linux ACPI enabled
BIOS ACPI Off/ Linux ACPI enabled
BIOS ACPI On/ Linux ACPI disabled
BIOS ACPI Off/ Linux ACPI disabled
Only one of the four is going to act as expected.
Of interest Microsoft encourages hardware vendors that package their
hardware with Windows products to work around bugs in the BIOS. This
is in contrast to getting the BIOS author to fix the bugs. Since the
work around is not often published this can cause problems for non
Windows software.
This is most important for laptop folks that want suspend, power down,
software control of the display etc.
--
T o m M i t c h e l l
mitch48-at-sbcglobal-dot-net
