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URL: http://www.digitalhermit.com/linux/hiresconsole.html This is a guide to getting a high-resolution console (non-X based) on your Linux machine. Besides allowing much more information to be presented at once, it also looks a lot cooler than that 80x25 screen. :) Please be aware that enabling any of these features could potentially damage your hardware. Though I've used these changes personally on dozens of monitors and LCD displays, there is the possibility that a particular mode or refresh rate or carelessness or divine intervention may damage the monitor or video card. I am in now way responsible if this happens. There are three main ways to get a high-res console:
This is the quickest and easiest way. At the LILO prompt, add vga=ask to the boot options. You'll be presented with a menu to select the video mode. The main problem with this method is that the font tends to look crowded on the screen and, except for the greater number of rows and columns, is not more readable.
From the SVGATextMode package description: SVGATextMode is a utility for reprogramming (S)VGA hardware, to improve the appearance of text consoles. SVGATextMode uses a configuration file (the default is /etc/TextConfig) with a syntax similar to X Window System's configuration file (Xconfig or XF86Config) to set up textmodes with higher resolution, larger font sizes, higher display refresh rates, etc. Theoretically, SVGATextMode can be used to program any text mode size, but your results will depend upon your VGA card. An advantage of SVGATextMode is that it's probably the fastest option. Text scroll speed is very good and characters are readable even with smaller fonts. Setup
First, install the package. This, of course, varies with the
distribution and version of Linux that you run. In most cases,
it's simply:
The next step is to gather information about your hardware. As the
root user, type:
You'll get output similar to the following:
The information you'll need is the VGA device. In this case a Matrox Millennium MGA 2064W card.
Next, determine the Horizontal Sync and Vertical Refresh capabilities
of your monitor. If you already have X configured, you can easily
look through your XF86Config or XMetroConfig (if using Metro-X) files
for the HorizSync and VertRefresh lines. For example:
You can also do a search on the Net Monitor Database, located at: http://www.griffintechnology.com/archive/monitor.html
For example, a search on Magnavox returns several matches. Drilling
down, I choose the 20CM64 and find that it supports:
Configure the /etc/TextConfig file
Open the /etc/TextConfig file in your favorite editor. The default
TextConfig will contain a standard, "works on anything" configuration
to edit. Look for the following lines and comment them out by placing
a # at the beginning of the line:
Also, comment out the warning message:
The next step is to scroll down through the TextConfig file and select your chipset. Unfortunately, it may not always be obvious. Try to choose a chipset based on the output from the previous lspci command. Among the supported chipsets are: "VGA" "S3" "ET4000" "TVGA8900" "TVGA8900" "WDC90C3x" "WDC90C0x" "ATI" "ATIMACH32" "ATIMACH64" "Cirrus" "Video7" "ALI" "AL2101" "OTI67" "OTI77" "OTI87" "SiS" "RealTek" "ARK" "ics5342" "NCR77C22E" "NCR77C32" "GVGA" "MX" "et6000" "tgui" "matrox" "NeoMagic"
For our example, we uncomment the Matrox-relevant stuff:
Continue to scroll down. You'll find various Option lines that you can
uncomment to activate. Read the descriptions for more information.
Eventually you'll see the HorizSync and VertRefresh lines.
Change these to the values you determined previously from the X
configuration file or from the monitor database. It's critical that
you do not just make up numbers here. Pushing monitors beyond spec,
especially the older ones, will release the magic smoke and send the
monitor to the service of that great video card in the sky.
I change mine to :
Next, you'll see a line for DefaultMode. This one is important, as it specifies the resolution SVGATextMode will try when called without any parameters. It's best to leave it as is. Further down are the rest of the modelines. Take a look at some of the valid modes that you can choose. Which ones are available depend upon your monitor capabilities and video card. Once you're done, save the file and exit. Testing the configuration
Now it's time to test. We can get a list of all available modelines with:
You'll get a long list. E.g.
Try one of the modelines with:
The screen should flicker for a second and you should have a high-res
display. Or, if you chose a modeline that's beyond the spec of your
monitor, you'll get a warning:
If, instead, your monitor suddenly goes berserk, type SVGATextMode by
itself on the prompt. You may have to do this blindly if the display
is unreadable. E.g.
Try other modelines too. Once you're satisfied that the mode works
correctly, place it somewhere in your initialization scripts. For example:
Try to enable SVGATextMode as early in the boot cycle as you can. I've noticed problems with some cards when SVGATextMode is enabled after loading X.
If SVGATextMode does not work correctly, try using the framebuffer console instead. NeoMagic chipsets, for example, are not well supported under SVGATextMode and can lock up your system. Most distributions now build frame buffer support by default and you can enable it by simply inserting a vga line to your /etc/lilo.conf file. If this is the case, skip to the end of this section where we configure lilo. There are a couple ways to take advantage of framebuffer support for the console. If you have the fbset package installed you can set the framebuffer mode by using the fbset utility. The other method is to specify a vga line within your lilo configuration file and reboot the system. The best place to learn more about the Framebuffer console is at http://linuxdoc.org/HOWTO/Framebuffer-HOWTO-1.html. (There I was doing research for this guide when I came across the above link. Go there, read, come back if you'd like :) ). Starting fbset
To use fbset first verify that the package is installed. If you are
using an RPM based distribution such as RedHat or Mandrake, you can do:
Next, you'll need to load the appropriate framebuffer module if support is not compiled into the kernel. For the next example we'll use an ATI example. Begin by changing to the /lib/modules/KERNEL_VERSION/kernel/drivers/video directory. [kwan@omega] cd /lib/modules/2.4.8-31KLL/kernel/drivers/video [kwan@omega] ls aty/ fbcon-mfb.o.gz mdacon.o.gz tdfxfb.o.gz aty128fb.o.gz fbcon-vga-planes.o.gz pm2fb.o.gz vga16fb.o.gz clgenfb.o.gz fbgen.o.gz radeonfb.o.gz cyber2000fb.o.gz hgafb.o.gz riva/ fbcon-hga.o.gz matrox/ sis/ Since I'm running an ATI card I load the aty128fb module with: [root@omega] modprobe aty128fb Once the module is loaded you can then attempt to set the mode. The fbset package will install a list of modelines in /etc/fb.modes. If you peek at them you'll see that they are similar to the list of X11 modes. To list the valid modes do:
[kwan@omega] grep ^mode /etc/fb.modes
You'll get a listing similar to this:
To install the mode, make sure that you are on a console screen and type:
Of course, substitute the mode that you want. With some cards there may be initial screen corruption. This can usually be fixed by switching to another console screen then switching back. Configuring Lilo The other method of enabling the framebuffer console is to specify the mode within your lilo configuration. As mentioned before, many of the distributions now build framebuffer support by default. If your initial bootup screen has a pretty penguin bitmapped logo (not the ASCII block pengiun) then you already have kernel support for framebuffer and can skip the kernel reconfiguration. Mandrake 8.x puts up a blue bootscreen that's also framebuffer based. In any case, try configuring the lilo first and if you get errors, then try the rebuild. First, we must build framebuffer support into the kernel. For this document, we'll assume that you understand the basics of rebuilding the kernel. If not, please consult the Kernel Rebuild Guide elsewhere on this site.
Change to the /usr/src/linux directory and begin the configuration process with:
You'll get the kernel configuration menu. For the 2.4.x series of kernels, select the Console Drivers option. Enable both "VGA Text Console" and "Video Mode Selection Support" Then, press [ENTER] on "Frame Buffer Support".
On the next screen, enable the following options:
Once the kernel is compiled and the modules built, edit the lilo.conf
entries and add the vga= line. The following table is from the linux
kernel documentation for the vesafb.
Or, in a friendlier decimal format:
To use the table, choose the resolution and color depth that works
for your card. Experiment with the settings to find one that works
well with your display. I.e., a laptop display often works best at
1024x768. My main monitor is set at 1280x1024. To get a 1024x768
resolution screen with 64K colors I choose 791. The relevant portion
of my lilo.conf now looks like:
Notice that the vga=791 is added under the image section. It's a good
idea to make two image sections -- one with the vga line set to normal,
the other with the mode of your choice. This allows you to easily drop
back in case there are problems. Note also that the default image is
set to linux_fb.
Once you've edited the lilo.conf file, go ahead and re-run lilo to install your changes. You will need to reboot your system for the changes to take effect. If there are problems then reboot the system and choose the non-framebuffer image. Matrox VideoCards If you're lucky enough to have a Matrox videocard (Millenium, Mystique, G100/200) then there are a few other optimization options available. This step does require a kernel rebuild, however, since none of the stock kernels I've encountered build these options in correctly.
The relevant section of the kernel config is in Console Drivers |
Frame Buffer Support. The following options are required:
Make sure that VESA VGA graphics console is not selected. Once you make
these changes, the lilo.conf stanza will look like this:
The following table is from the Matrox frame buffer documentation included
with the kernel sources.
Convert the values in the above table from hex to decimal and place it in your lilo configuration. ATI Videocards
The ATI entry in the lilo.conf file has a slightly different syntax. Instead of using the table, you specify the mode directly on the "append=" line. For example:
boot=/dev/hda
map=/boot/map
install=/boot/boot.b
vga=normal
default=linux-2.4.8
keytable=/boot/us.klt
lba32
prompt
timeout=50
message=/boot/message
image=/boot/bzImage-2.4.17
label=preemptible
root=/dev/hda3
read-only
optional
append="video=aty128fb:1024x768"
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