Linux and UNIX Man Pages

Linux & Unix Commands - Search Man Pages

acpi_video(4) [freebsd man page]

ACPI_VIDEO(4)						   BSD Kernel Interfaces Manual 					     ACPI_VIDEO(4)

acpi_video -- ACPI Video Extensions driver SYNOPSIS
device acpi_video DESCRIPTION
This driver uses the ACPI Video Extensions to control display switching and backlight brightness. The availability of the sysctl(8) vari- ables depends on the functions offered by the host's ACPI implementation. SYSCTL VARIABLES
The following sysctls are currently implemented, where <device> is crt, lcd, or tv:<device>.active Current state of the output device.<device>.levels List of supported brightness levels.<device>.brightness Current brightness level of the device.<device>.fullpower Preset brightness level to be used in full power mode.<device>.economy Preset brightness level to be used in economy mode. Defaults for these variables can be set in sysctl.conf(5), which is parsed at boot-time. SEE ALSO
acpi(4), loader.conf(5), sysctl.conf(5), sysctl(8) HISTORY
The acpi_video driver first appeared in FreeBSD 5.3. AUTHORS
The acpi_video driver was written by Taku YAMAMOTO <>. This manual page was written by Mark Santcroos <>. BUGS
Some systems only perform output switching via SMM even though they export the proper information via ACPI. On such systems, the proper hotkeys or OEM driver (for example, acpi_toshiba(4)) must be used instead. BSD
November 8, 2004 BSD

Check Out this Related Man Page

ACPIVGA(4)						   BSD Kernel Interfaces Manual 						ACPIVGA(4)

acpivga -- ACPI Display Adapter and Output Devices SYNOPSIS
acpivga* at acpi? acpiout* at acpivga? DESCRIPTION
The acpivga driver provides generic support for brightness control and output switching, through ACPI video extensions. The ACPI specifica- tion requires that systems containing a built-in display adapter implement these extensions in their ACPI BIOS. The driver handles brightness hotkeys and display switch hotkeys. In addition, the following sysctl(8) read/write variables are provided (when hardware support is available): hw.acpi.acpivga0.bios_switch BIOS output switching policy. This boolean variable controls the behavior of the BIOS when a display switch hotkey is pressed. 1 the BIOS should automatically switch outputs, with no interaction from acpivga. 0 the BIOS should only notify acpivga of the desired output state changes. hw.acpi.acpiout0.brightness Brightness level. This integer variable typically ranges from 0 to 100, but any integer value is accepted (the driver uses the clos- est brightness level supported by the device). Please note, however, that future versions of acpivga may remove these sysctl(8) variables without prior notice. SEE ALSO
acpi(4), vga(4), sysctl(8) Microsoft Corporation, Mobile System Displays and Windows, Version 1.2c,, December 4, 2001. HISTORY
The acpivga driver appeared in NetBSD 6.0. AUTHORS
Gregoire Sutre <> CAVEATS
The acpivga driver only supports PCI/PCI-X/PCI-E display adapters. Many ACPI BIOSes implement only part of the ACPI video extensions. In particular, display output switching via these extensions often does not work. For this reason, acpivga enables hw.acpi.acpivga0.bios_switch by default. If the display switch hotkey does not work with this default setting, try setting hw.acpi.acpivga0.bios_switch to 0. Brightness level should be controlled via wsconsctl(8) instead of sysctl(8). BSD
October 28, 2010 BSD
Man Page

10 More Discussions You Might Find Interesting

1. UNIX for Dummies Questions & Answers

FreeBSD 4.6 Video Settings for Xwindows

I have set-up FreeBSD on an HP Vectra Intel Based PC, now when I go to /stand/sysinstall and "do a post installation configuration" and try to set-up the XFree86 server under Video card the model of my card does not exist. My video card model is SiS 6205 but FreeBSD supports or listed only 5205. I... (5 Replies)
Discussion started by: charlie499
5 Replies

2. What is on Your Mind?

World's strongest economy

Hi all, It just came to my mind to ask your opinion that which country is the world's strongest economy at the moment and would be there at top for next 10 years. (2 Replies)
Discussion started by: tayyabq8
2 Replies

3. Linux

kernel: ACPI:

I've noted the following within /var/log/messages, any idea how to check whether they are related to hardware/driver problems, pls? :confused: Sep 9 11:56:08 triton smartd: Device: /dev/sda, opened Sep 9 11:56:08 triton kernel: ACPI: LAPIC (acpi_id lapic_id enabled) Sep 9 11:56:08... (1 Reply)
Discussion started by: jon80
1 Replies

4. UNIX and Linux Applications

Apache+Perl: interruption of STDIN

Hello dear community! I have faced with a trouble which I trying to solve for a long time. I have service of video streaming. And I have web and video roles for servers. Video servers upload video using SWFUpload and then stream it. Issue became during uploading of video. In random time... (3 Replies)
Discussion started by: sevmax
3 Replies

5. UNIX for Advanced & Expert Users

acpi table contents

Can anyone please tell me what information is present in the acpi tables ? (4 Replies)
Discussion started by: vishwamitra
4 Replies

6. UNIX for Advanced & Expert Users

Video Cards :: Video Memory Intercept and Redirect

I need a broad spectrum understanding on this subject, and any help would be greatly appreciated. First of all, as I understand it... The way the video hardware works is the CPU sends information about input and possible changes to the display, the video card receives these changes, makes the... (2 Replies)
Discussion started by: ciNG
2 Replies

7. What is on Your Mind?

Need video lectures

Hi All, I donno whether i`m posting in crt place r not , if not moderator please move my post to crt place. Can any one of u , pls gimme da links to learn Perl scripting , video lectures (for free + download/online) Thx in adv (1 Reply)
Discussion started by: radha254
1 Replies

8. What is on Your Mind?

Post An Interesting Video

YouTube is one of the most incredible services on the internet. In a break from our 'regular' "Post a Cool Music Video", use this thread to post any interesting (and copyright / family friendly!) YouTube videos. To get the ball rolling... lX6JcybgDFo Actually, why restrict it only to... (12 Replies)
Discussion started by: Scott
12 Replies

9. What is on Your Mind?

Video Overview of the Vue.js UserCP

Here is my second live video screencast (in my life, using Camtasia) with voice for the new usercp: Overview of the Vue.js UserCP Shout outs to Don Cragun, Corona688, Rudi, Wolf, Made in Germany, stomp, Ravinder, Creative Tim, PubNub and others in the video. Thanks. If you are... (1 Reply)
Discussion started by: Neo
1 Replies

10. What is on Your Mind?

Top 5 Roadblocks to a Secure Cyberspace in 2019 | YouTube Video

Here is a shout-out to wisecracker, who selected the sound track for this new video: Top 5 Roadblocks to a Secure Cyberspace in 2019 (7 Replies)
Discussion started by: Neo
7 Replies