NAME
vbetool - run real-mode video BIOS code to alter hardware state
SYNOPSIS
vbetool [[vbestate save|restore]|[vbemode set|get]|[vgamode]|[dpms on|off|standby|suspend|reduced]|[post]|[vbestate on|off]]
DESCRIPTION
vbetool uses lrmi in order to run code from the video BIOS. Currently, it is able to alter DPMS states, save/restore video card state and attempt to initialize the video card from scratch.
OPTIONS
vbetool
takes the following options:
vbestate
vbetool will use the VESA 0x4f0f extensions to save or restore hardware state. This will be sent to or read from stdin. This information is highly hardware specific - do not attempt to restore state saved from a different machine. This command will not work unless you are at a text console, as it interferes badly with X.
|
dpms |
vbetool will use the VESA 0x4f10 extensions to alter the power management state of your screen. "On", "off", "standby", "suspend" and "reduced" are acceptable further options and determine which state will be activated. |
vbemode
vbetool will get or set the current VESA mode. "get" will return the current mode number on stdout - "set" will set the mode to the next argument.
vgamode
vbetool will set the legacy VGA mode to the following numeric argument.
|
post |
vbetool will attempt to run BIOS code located at c000:0003. This is the code run by the system BIOS at boot in order to intialise the video hardware. Note that on some machines (especially laptops), not all of this code is present after system boot - as a result, executing this command may result in undefined behaviour. This command must be run from a text console, as it will otherwise interfere with the operation of X. |
vgastate
vbetool will enable or disable the current video card. On most hardware, disabling will cause the hardware to stop responding until it is reenabled. You probably don’t want to do this if you’re using a framebuffer.
BUGS
Switching dpms modes may interact badly with X on some systems.
The vbestate command may behave in strange ways.
The post command may result in the execution of arbitrary code that happens to be lying around in the area where chunks of your video BIOS used to be.
The VESA specification does not require that "vbemode get" provides the correct mode if the current mode was set via some means other than the VESA BIOS extensions.
AUTHOR
vbetool was written by Matthew Garrett <mjg59 [AT] srcf.org>, based on code from read-edid by John Fremlin <john [AT] fremlin.de>, LRMI (http://sourceforge.net/projects/lrmi/) and XFree (http://www.xfree86.org). It is released under the terms of the GNU General Public License.