Re: turning off (LCD+) backlight without suspending
> are you sure the back light stays on when you close the
> laptop? my laptop
> (ARM TS759) has a switch ...
[--Craig the physicist]
Sure does. Closed it to a tiny crack and its still on.
Doesn't seem to be any such switch on the OB. (On many
machines closing the lid autmatically suspends it, so I'm
kind of glad I don't have one as I want to use the audio
components with the lid closed. Ooo! Wearables anyone
(watch the ebay prices of OB800's pop up! -- NOT!)
> Well, if it was just an OS "feature" then you can probably chvt to an
> empty console. 12 maybe. With no contents to display it may save a
> *little* bit of juice.
[--Heather the star]
OK, chvt 12 makes the screen blank but it doesn't turn off
the backlight. Yet! But after I left the OB on a console
for a while to write the other message about the showkey
results I discovered that it does turn the backlight off
when the console blanking code kicks in (is this a kernel
feature)? Cool. Thanks Linus! Thanks Heather!
So when I want to travel, instead of 'xlock -blank' in X,
I'll have my script 'sudo chvt 12' and let it turn itself
off after a couple of minutes.
And maybe when I have nothing better to do I'll poke around
in the kernel code and see if I can find the console
blanking stuff.
> If it has dpms features you might be able to convince X to put it in
> that mode - however, running X may itself steal juice, can't say if that
> would be a win.
I tried all the below, and they just blank the screen but
leave the backlight on.
xlock -blank
xlock -blank -dpmsoff 0
xlock -blank -dpmssuspend 0
> For power savings purposes I long since changed my standard mode so that
> I have almost no services running, and only two getty's. mingetty actually.
> So the standard runlevel 2 for me is very stripped-bare. I use runlevel 5
> for "like my normal workstation" mode, in other words, more consoles, apache
> running some virtual servers, etc. You might benefit from the same.
I haven't gone quite so far but that's kind of like what
I've done. I combined my network environment with my power
environment and a little script that copies symlinks
network.opts, hosts, etc., to a version for my lan
environment and stops or starts some services. Since
runlevels didn't really handle that kind of stuff and netenv
or cardctl didn't quite to it for me either, I rolled my
own. Heck, it even puts wwwoffle in -online or -offline
mode for me and restarts it on any change in networking
(since it gets confused when networks change).
--
Tony
Reply to: