> Sender: cummings@hammer (Kevin Cummings)
quoted text >
> 2) The boot loaded the 8x8 font after not recognizing my video card.
> OK, it's an EGA, so my screen is now 80x43. LINUX thinks my
> screen is 80x50! And it sets up the TERM variable of my login
> shells to con80x50. It also tells my video controller that I
> must have 50 line per screen, because 17 lines disappear below
> line 43 before the display starts to scroll! Can I give a simple
> test to the video people to discern VGA from EGA? It was published
> in DDJ a while back when they started the Graphics column.
> It involves calling a VGA BIOS interrupt. EGAs (and CGAs, etc)
> return the function number, while VGAs return a 0 error code.
> Very simple.
>
> 2a) I want to add my EGA extended text modes to the setup.c code.
> I guess if I am patching code for my own use, I can just add
> it at the fall through label where everything else failed.
> In order to do more (and send my new code back to Linus for
> inclusing into the real source), does anyone know how to detect
> a GENOA EGA BIOS? I can find GENOA copyright notices in the EGA
> BIOS. Are these notices in the same location in EVERY GENOA
> EGA card? Does the SVGA book mention anything about EGA cards?
>
> 2b) OK, so I may be buying an "S3" based SVGA card soon (it was going
> to be Real Soon Now, but my 70MB disk had a head crash last night,
> bad timing, huh?). Is there any "clues" for these new cards?
> S3 text modes should still be limited to 16 colors, regardless
> of the graphics modes capabilities (with Sierra RAMDACs).
> (It was going to be the Diamond Stealth Hi-Color w/1MB, in case
> anyone was interested.)
>
Plase...
Somebody tell me how to make use of the folowing stuff.
I really would like all this stuff about video mode to end.
And the following article shows how. I just have no experience
at all in poking with PC VGA.....
quoted text > From:
paula@atc.boeing.com (Paul Allen)
>
> I took a few days off, and have only caught up through digest
> #104! Would you guys slow down a bit??? :-)
>
> Several people have commented that changing VGA modes via an
> ioctl will be hard because SVGA registers are undocumented
> and all different. The mysterious nature of SVGA registers
> appears to be mostly myth. Since the registers on a VGA
^^^^^^^^^^^
quoted text > can all be read, it is fairly simple to write a program to
> discover what to put in the registers for any given video
> mode.
>
> For an example of how this can be used to implement VGA mode-
> switching in protected mode, take a look at the Minix port of
> the MGR window system. On bellcore.com, in /pub/mgr/minix,
> you will find the latest version of the Minix port of MGR.
> The vgaregs.zip file contains an MSDOS program that can be
^^^^^^^^^^^
quoted text > used to read the VGA registers. The videodef.h file is a
> sample of what's produced by vgaregs. To switch to a different
> mode, one simply blasts the appropriate set of values into the
> registers. (Well, it may not be quite that simple, but you
> get the point.) The number of people actually running MGR
> under Minix is probably still fairly small, but I've seen
> reports of success from several people and no reports of VGA
> incompatibility. I run MGR in 800x600x2 mode on my no-name
> clone SVGA, and have had no problems.
I tried the program and it output te desired include file.
The problem is:
How do I make use of it ?
quoted text > In the Minix VGA implementation, there are four special files
> in /dev corresponding to text mode and three graphics modes.
> /dev/screen is a link to the graphics device to use for MGR.
> Two programs, tmode and gmode, are used to set either text
> mode or the graphics mode selected by /dev/screen. Linux
> wouldn't have to limit the choices like this.
>
> So, no further SVGA documentation is needed. All that's needed
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Well... at least a book that describes the general architecture of
a VGA and superVGA .... ( At least for me )
Anybody has a good title ?
Damiano
