Turn off display/backlight

[Kevin Oberman]

> Date: Tue, 15 Jul 2003 23:13:41 +0200 (MEST)
> From: Markus D. <sm4tnp8 at gmx.net>
> Sender: owner-freebsd-mobile at freebsd.org
> 
> Hello,
> 
> is there any way to turn off the display (aka screensaver) for the console
> completely, with switching off the backlight of my laptop's lcd? I use
> 5.1-Release now. With 4-stable I used the apm_saver, which did this. But now with
> ACPI the apm_saver doesn't work anymore even if i turn apm on.

This is a common issue with ACPI on laptops. I have it on my T30 and I
have seen others with different brands and models report it. I don't
have a fix at this time. (Since I don't work on ACPI code, I won't be
finding it,)

The work-around is to use apm and not ACPI.
To switch to APM, edit /boot/loader.conf and add:
apm_load="YES"
Edit /boot/device.hints and add:
hint.acpi.0.disabled="1"
and change the value of hint.apm.0.disabled to "0"

Make sure that your rc.conf contains:
apm_enable="YES"

Once that is done, you should be able to turn off the back-light any
way you could under V4.

Hopefully APM will continue to mature and these issues will get
settled over a bit of time.
-- 
R. Kevin Oberman, Network Engineer
Energy Sciences Network (ESnet)
Ernest O. Lawrence Berkeley National Laboratory (Berkeley Lab)
E-mail: oberman at es.net			Phone: +1 510 486-8634