fbset(8)                   Linux frame buffer utils                   fbset(8)

       fbset - show and modify frame buffer device settings

       fbset [options] [mode]

       This documentation is out of date!!

       fbset is a system utility to show or change the settings of the frame
       buffer device. The frame buffer device provides a simple and unique
       interface to access different kinds of graphic displays.

       Frame buffer devices are accessed via special device nodes located in
       the /dev directory. The naming scheme for these nodes is always fb<n>,
       where n is the number of the used frame buffer device.

       fbset uses an own video mode database located in /etc/fb.modes. An
       unlimited number of video modes can be defined in this database. For
       further information see fb.modes(5).

       If no option is given, fbset will display the current frame buffer

       General options:

              --help, -h
                     display an usage information

              --now, -n
                     change the video mode immediately. If no frame buffer
                     device is given via -fb , then this option is activated
                     by default

              --show, -s
                     display the video mode settings. This is default if no
                     further option or only a frame buffer device via -fb is

              --info, -i
                     display all available frame buffer information

              --verbose, -v
                     display information what fbset is currently doing

              --version, -V
                     display the version information about fbset

              --xfree86, -x
                     display the timing information as it's needed by XFree86

       Frame buffer device nodes:

              -fb <device>
                     device gives the frame buffer device node. If no device
                     via -fb is given, /dev/fb0 is used

              Video mode database:

              -db <file>
                     set an alternative video mode database file (default is
                     /etc/fb.modes), see also fb.modes(5)

       Display geometry:

              -xres <value>
                     set visible horizontal resolution (in pixels)

              -yres <value>
                     set visible vertical resolution (in pixels)

              -vxres <value>
                     set virtual horizontal resolution (in pixels)

              -vyres <value>
                     set virtual vertical resolution (in pixels)

              -depth <value>
                     set display depth (in bits per pixel)

              --geometry, -g ...
                     set all geometry parameters at once in the order <xres>
                     <yres> <vxres> <vyres> <depth>, e.g.  -g 640 400 640 400

                     make the physical resolution match the virtual resolution

       Display timings:

              -pixclock <value>
                     set the length of one pixel (in picoseconds). Note that
                     the frame buffer device may only support some pixel

              -left <value>
                     set left margin (in pixels)

              -right <value>
                     set right margin (in pixels)

              -upper <value>
                     set upper margin (in pixel lines)

              -lower <value>
                     set lower margin (in pixel lines)

              -hslen <value>
                     set horizontal sync length (in pixels)

              -vslen <value>
                     set vertical sync length (in pixel lines)

              --timings, -t ...
                     set all timing parameters at once in the order <pixclock>
                     <left> <right> <upper> <lower> <hslen> <vslen>, e.g.  -g
                     35242 64 96 35 12 112 2

       Display flags:

              -hsync {low|high}
                     set the horizontal sync polarity

              -vsync {low|high}
                     set the vertical sync polarity

              -csync {low|high}
                     set the composite sync polarity

              -extsync {false|true}
                     enable or disable external resync. If enabled the sync
                     timings are not generated by the frame buffer device and
                     must be provided externally instead. Note that this
                     option may not be supported by every frame buffer device

              -bcast {false|true}
                     enable or disable broadcast modes. If enabled the frame
                     buffer generates the exact timings for several broadcast
                     modes (e.g. PAL or NTSC). Note that this option may not
                     be supported by every frame buffer device

              -laced {false|true}
                     enable or disable interlace. If enabled the display will
                     be split in two frames, each frame contains only even and
                     odd lines respectively. These two frames will be
                     displayed alternating, this way twice the lines can be
                     displayed and the vertical frequency for the monitor
                     stays the same, but the visible vertical frequency gets

              -double {false|true}
                     enable or disable doublescan. If enabled every line will
                     be displayed twice and this way the horizontal frequency
                     can easily be doubled, so that the same resolution can be
                     displayed on different monitors, even if the horizontal
                     frequency specification differs. Note that this option
                     may not be supported by every frame buffer device

       Display positioning:

              -move {left|right|up|down}
                     move the visible part of the display in the specified

              -step <value>
                     set step size for display positioning (in pixels or pixel
                     lines), if -step is not given display will be moved 8
                     pixels horizontally or 2 pixel lines vertically

       To set the used video mode for X insert the following in rc.local:

              fbset -fb /dev/fb0 vga

       and make the used frame buffer device known to X:

              export FRAMEBUFFER=/dev/fb0


       fb.modes(5), fbdev(4)

       Geert Uytterhoeven <Geert.Uytterhoeven@cs.kuleuven.ac.be>

       Roman Zippel <zippel@fh-brandenburg.de>
              man files

local                              July 1998                          fbset(8)