1fbset(8) Linux frame buffer utils fbset(8)
2
6 fbset - show and modify frame buffer device settings
7
9 fbset [options] [mode]
10
12 This documentation is out of date!!
13 fbset is a system utility to show or change the settings of the frame
15 buffer device. The frame buffer device provides a simple and unique
16 interface to access different kinds of graphic displays.
17 Frame buffer devices are accessed via special device nodes located in
19 the /dev directory. The naming scheme for these nodes is always fb<n>,
20 where n is the number of the used frame buffer device.
21 fbset uses an own video mode database located in /etc/fb.modes. An
23 unlimited number of video modes can be defined in this database. For
24 further information see fb.modes(5).
25
27 If no option is given, fbset will display the current frame buffer set‐
28 tings.
29 General options:
31 --help, -h
33 display an usage information
34 --now, -n
36 change the video mode immediately. If no frame buffer
37 device is given via -fb , then this option is activated
38 by default
39 --show, -s
41 display the video mode settings. This is default if no
42 further option or only a frame buffer device via -fb is
43 given
44 --info, -i
46 display all available frame buffer information
47 --verbose, -v
49 display information what fbset is currently doing
50 --version, -V
52 display the version information about fbset
53 --xfree86, -x
55 display the timing information as it's needed by XFree86
56 Frame buffer device nodes:
58 -fb <device>
60 device gives the frame buffer device node. If no device
61 via -fb is given, /dev/fb0 is used
62 Video mode database:
64 -db <file>
66 set an alternative video mode database file (default is
67 /etc/fb.modes), see also fb.modes(5)
68 Display geometry:
70 -xres <value>
72 set visible horizontal resolution (in pixels)
73 -yres <value>
75 set visible vertical resolution (in pixels)
76 -vxres <value>
78 set virtual horizontal resolution (in pixels)
79 -vyres <value>
81 set virtual vertical resolution (in pixels)
82 -depth <value>
84 set display depth (in bits per pixel)
85 --geometry, -g ...
87 set all geometry parameters at once in the order <xres>
88 <yres> <vxres> <vyres> <depth>, e.g. -g 640 400 640 400
89 4
90 -match
92 make the physical resolution match the virtual resolution
93 Display timings:
95 -pixclock <value>
97 set the length of one pixel (in picoseconds). Note that
98 the frame buffer device may only support some pixel
99 lengths
100 -left <value>
102 set left margin (in pixels)
103 -right <value>
105 set right margin (in pixels)
106 -upper <value>
108 set upper margin (in pixel lines)
109 -lower <value>
111 set lower margin (in pixel lines)
112 -hslen <value>
114 set horizontal sync length (in pixels)
115 -vslen <value>
117 set vertical sync length (in pixel lines)
118 --timings, -t ...
120 set all timing parameters at once in the order <pixclock>
121 <left> <right> <upper> <lower> <hslen> <vslen>, e.g. -g
122 35242 64 96 35 12 112 2
123 Display flags:
125 -hsync {low|high}
127 set the horizontal sync polarity
128 -vsync {low|high}
130 set the vertical sync polarity
131 -csync {low|high}
133 set the composite sync polarity
134 -extsync {false|true}
136 enable or disable external resync. If enabled the sync
137 timings are not generated by the frame buffer device and
138 must be provided externally instead. Note that this
139 option may not be supported by every frame buffer device
140 -bcast {false|true}
142 enable or disable broadcast modes. If enabled the frame
143 buffer generates the exact timings for several broadcast
144 modes (e.g. PAL or NTSC). Note that this option may not
145 be supported by every frame buffer device
146 -laced {false|true}
148 enable or disable interlace. If enabled the display will
149 be split in two frames, each frame contains only even and
150 odd lines respectively. These two frames will be dis‐
151 played alternating, this way twice the lines can be dis‐
152 played and the vertical frequency for the monitor stays
153 the same, but the visible vertical frequency gets halved
154 -double {false|true}
156 enable or disable doublescan. If enabled every line will
157 be displayed twice and this way the horizontal frequency
158 can easily be doubled, so that the same resolution can be
159 displayed on different monitors, even if the horizontal
160 frequency specification differs. Note that this option
161 may not be supported by every frame buffer device
162 Display positioning:
164 -move {left|right|up|down}
166 move the visible part of the display in the specified
167 direction
168 -step <value>
170 set step size for display positioning (in pixels or pixel
171 lines), if -step is not given display will be moved 8
172 pixels horizontally or 2 pixel lines vertically
173
175 To set the used video mode for X insert the following in rc.local:
176 fbset -fb /dev/fb0 vga
178 and make the used frame buffer device known to X:
180 export FRAMEBUFFER=/dev/fb0
182
184 /dev/fb*
185 /etc/fb.modes
186
188 fb.modes(5), fbdev(4)
189
191 Geert Uytterhoeven <Geert.Uytterhoeven@cs.kuleuven.ac.be>
192 Roman Zippel <zippel@fh-brandenburg.de>
194 man files
195local July 1998 fbset(8)