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Roline

Member

From: Netherlands

Registered: 2009-12-05

Posts: 207

Website

[Solved]Backlight set max brightness

The maximum brightness of my backlight isn't that bright at all. So I would like to know if there is a way to change the maximum value to a higher value? /sys/class/backlight/acpi_video0/ shows in the max_brightness file: "9". I tried to change the value but even as root I'm unable to change the file. Is there a way to achieve more brightness?

Last edited by Roline (2010-05-08 12:26:57)

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ewaller

Administrator

From: Pasadena, CA

Registered: 2009-07-13

Posts: 19,804

Re: [Solved]Backlight set max brightness

You did not provide much info about your system.  I assume it is a laptop.
It appears your system uses ACPI for backlight brightness.  I am still one of the old fashioned /proc kind of users.  I've not fully groked all this new fangled /sys stuff (yet)

Take a look around in /proc/acpi for pertinent files.  The following works on my system:

[root@odin ~]# cat /proc/acpi/video/OVGA/DD03/brightness
levels:  0 10 20 30 40 50 60 70 80 90 100
current: 90
[root@odin ~]# echo 100 > /proc/acpi/video/OVGA/DD03/brightness
[root@odin ~]# cat /proc/acpi/video/OVGA/DD03/brightness
levels:  0 10 20 30 40 50 60 70 80 90 100
current: 100

edit: Fixed code clip

Last edited by ewaller (2010-05-01 21:31:40)

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Roline

Member

From: Netherlands

Registered: 2009-12-05

Posts: 207

Website

Re: [Solved]Backlight set max brightness

Thanks!

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Bitbucket - DeviantART - Userstyles
*Currently Not Using Arch