155 lines
6.7 KiB
HTML
155 lines
6.7 KiB
HTML
|
<!--startcut ==========================================================-->
|
||
|
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2//EN">
|
||
|
<HTML>
|
||
|
<HEAD>
|
||
|
<title>SVGATextMode Issue 21</title>
|
||
|
</HEAD>
|
||
|
<BODY BGCOLOR="#FFFFFF" TEXT="#000000" LINK="#0000FF" VLINK="#0020F0"
|
||
|
ALINK="#FF0000">
|
||
|
<!--endcut ============================================================-->
|
||
|
|
||
|
<H4>
|
||
|
"Linux Gazette...<I>making Linux just a little more fun!</I>"
|
||
|
</H4>
|
||
|
|
||
|
<P> <HR> <P>
|
||
|
<!--===================================================================-->
|
||
|
|
||
|
<center>
|
||
|
<H2>SVGATextMode</H2>
|
||
|
<H4>By Larry Ayers,
|
||
|
<a href="mailto:layers@marktwain.net">layers@marktwain.net</a></H4>
|
||
|
</center>
|
||
|
|
||
|
|
||
|
<center><h1>Fit More Text On Your Console Screen</h1></center>
|
||
|
|
||
|
<center><h3>Introduction</h3></center>
|
||
|
|
||
|
<p>This summer a new version of <b>SVGATextMode</b> was released, and
|
||
|
thinking that many Linux users might be unfamiliar with the package, I put
|
||
|
together this review as an introduction to a versatile and useful console
|
||
|
utility.
|
||
|
|
||
|
<p>Typically, Linux distributions use LILO as the boot loader, which refers to
|
||
|
the file <i>/etc/lilo.conf</i> for instructions. One of the lines in the file
|
||
|
is <kbd>vga = </kbd>, with either the number of a console video mode following
|
||
|
the "=", or the word <i>ask</i>. If "ask" is specified, the Linux boot
|
||
|
process is interrupted and you are asked which (EGA) video mode you prefer. An
|
||
|
option (thankfully!) is also provided allowing the user to peruse a menu of
|
||
|
available console video modes, which varies depending on the video chipset.
|
||
|
With my generic S3 Virge card, these modes are offered:
|
||
|
|
||
|
<ul>
|
||
|
<li>80x25
|
||
|
<li>80x50
|
||
|
<li>80x43
|
||
|
<li>80x28
|
||
|
<li>80x30
|
||
|
<li>80x34
|
||
|
<li>80x60
|
||
|
<li>132x25
|
||
|
<li>132x43
|
||
|
</ul>
|
||
|
|
||
|
<p>It's nice to have a choice of video modes (which determine the screen font
|
||
|
size) but these boot-time options just scratch the surface of what the newer video cards
|
||
|
and monitors offer. SVGATextMode is a utility which borrows some of the
|
||
|
techniques which the X-Window system uses to exploit the resources of your
|
||
|
video system and applies them to the console screen.
|
||
|
|
||
|
<center><h3>How It Works</h3></center>
|
||
|
|
||
|
<p>SVGATextMode actually reprograms the registers of your video card, allowing
|
||
|
many more modes than the preprogrammed modes available at boot-up. It borrows
|
||
|
some of the techniques used by XFree86 in order to make available more console
|
||
|
video modes. The modes provided by your video-card BIOS are EGA modes, and
|
||
|
they run at a low refresh-rate and dot-clock compared to those used by
|
||
|
X-windows.
|
||
|
|
||
|
<p>The program can be either started at boot-time from one of the init-files,
|
||
|
or at any time from the console prompt. When it starts a configuration file
|
||
|
(<kbd>/etc/TextConfig</kbd>) is parsed. The defaults are very conservative.
|
||
|
The file needs to be read and edited before any real advantage can be obtained
|
||
|
from the program. This is due to the vast differences in capability between
|
||
|
various video cards and monitors. As in X configuration, the correct values
|
||
|
for your monitor's horizontal and vertical refresh rates need to be entered in
|
||
|
the <b>TextConfig</b> file. If you've successfully configured X you shouldn't
|
||
|
have any problems with SVGATextMode.
|
||
|
|
||
|
<center><h3>Configuration and Use</h3></center>
|
||
|
|
||
|
<p>SVGATextMode is what I consider to be a "mature" package, in that it has
|
||
|
been under development long enough to have received contributions and bugfixes
|
||
|
from a worldwide community of users. Many video cards are supported, though I
|
||
|
don't think quite as many as XFree86 supports.
|
||
|
|
||
|
<p>In the default <kbd>/etc/TextConfig</kbd> file many of the lines are
|
||
|
high-resolution modes contributed by users. Once you have entered your video
|
||
|
chipset and monitor timings into the file, the command <kbd>SVGATextMode -n
|
||
|
[mode]</kbd> will let you know if your hardware can support the mode without
|
||
|
actually starting the program. Once you've found some promising modes just
|
||
|
eliminate the "-n" from the command and with any luck you'll have the new
|
||
|
text mode visible on your console screen. Possibly the screen will be
|
||
|
corrupted. Running the SVGAlib utility <b>savetextmode</b> before trying a
|
||
|
new mode, then if corruption appears <b>restoretextmode</b> afterwards ought
|
||
|
to allow recovery of your previous default text mode. It will take some
|
||
|
experimentation, but the package is very well documented and is worth the
|
||
|
trouble.
|
||
|
|
||
|
<p>There are some included modes with 160-character wide screens, which can be
|
||
|
very useful while running an editor which allows two 80-character pages to be
|
||
|
displayed side-by-side. Emacs can do this, and there is a LISP package
|
||
|
available called follow-mode which allows both pages to scroll relative to
|
||
|
each other.
|
||
|
|
||
|
<p>SVGATextMode doesn't just allow more characters to be displayed on the
|
||
|
screen. Even relatively low-resolution modes will look crisper and be easier
|
||
|
to read due to the higher refresh rates typically used. The most dramatic
|
||
|
advantages, naturally, are evident with newer, more powerful video-cards and
|
||
|
large monitors, but even with my middle-of-the-road equipment the utility is
|
||
|
well worth using.
|
||
|
|
||
|
<center><h3>Caveats</h3></center>
|
||
|
|
||
|
<p>If you use Dosemu from the console there can be problems. I have to reset
|
||
|
the text-mode to my old default 80x43 mode before starting Dosemu or I get
|
||
|
unrecoverable corruption requiring a reboot. I haven't had any problems
|
||
|
switching from a console session to X and back, but, just as with X-windows,
|
||
|
performance varies depending upon the video-card and monitor involved.
|
||
|
Read the documentation; it's very complete and a great help while getting
|
||
|
started.
|
||
|
|
||
|
<center><h3>Availability</h3></center>
|
||
|
|
||
|
<p>The source package (version 1.6) can be retrieved from the Sunsite archive site or one of
|
||
|
its mirrors, in this <a href="ftp://sunsite.unc.edu/pub/Linux/utils/console">directory</a>.
|
||
|
A binary package for Redhat systems is available
|
||
|
<a
|
||
|
href="ftp://sunsite.unc.edu/pub/Linux/distributions/redhat/contrib/i386/">here</a>,
|
||
|
and a Debian binary can be downloaded from
|
||
|
<a href="ftp://sunsite.unc.edu/pub/Linux/distributions/hamm/hamm/binary-i386/admin">
|
||
|
here</a>.
|
||
|
|
||
|
|
||
|
<!--===================================================================-->
|
||
|
<P> <hr> <P>
|
||
|
<center><H5>Copyright © 1997, Larry Ayers<BR>
|
||
|
Published in Issue 21 of the Linux Gazette, September 1997</H5></center>
|
||
|
|
||
|
<!--===================================================================-->
|
||
|
<P> <hr> <P>
|
||
|
<A HREF="./index.html"><IMG ALIGN=BOTTOM SRC="../gx/indexnew.gif"
|
||
|
ALT="[ TABLE OF CONTENTS ]"></A>
|
||
|
<A HREF="../index.html"><IMG ALIGN=BOTTOM SRC="../gx/homenew.gif"
|
||
|
ALT="[ FRONT PAGE ]"></A>
|
||
|
<A HREF="./ppp.html"><IMG SRC="../gx/back2.gif"
|
||
|
ALT=" Back "></A>
|
||
|
<A HREF="./icewm.html"><IMG SRC="../gx/fwd.gif" ALT=" Next "></A>
|
||
|
<P> <hr> <P>
|
||
|
<!--startcut ==========================================================-->
|
||
|
</BODY>
|
||
|
</HTML>
|
||
|
<!--endcut ============================================================-->
|
||
|
|