"full-screen" DOS window doesn't fill screen

"full-screen" DOS window doesn't fill screen

Post by ynotsso » Sun, 08 Jun 2008 05:00:28


I have an old DOS program that runs in a cmd.exe window which can be made to
use the full screen with Alt-Enter. This works properly on another win200
machine, but on a Toshiba laptop the full screen mode fills the width but
NOT the height of the screen.

I've made sure that the Properties and the Console Windows Properties of the
C:\winnt\system32\cmd.exe window are the same on both machines, using Raster
Fonts 8x12 and the same Layout, Screen Buffer 80x420 and Window Size 80x25.

Still, the fullscreen mode on the laptop doesn't fill the vertical of the
screen for any cmd.exe application, even just a command prompt.

What am I mssing here, please?
 
 
 

"full-screen" DOS window doesn't fill screen

Post by Sjouke Bur » Mon, 09 Jun 2008 08:32:45


In the dark ages I had one at wotk which had a FN key
function to toggle just that "DOS" screen property.
So check out your function keys.

 
 
 

"full-screen" DOS window doesn't fill screen

Post by Ted Davi » Mon, 09 Jun 2008 08:56:24


Most likely, you are missing the fact that the digital display has fixed
numbers of pixels vertical and horizontal (and therefore a fixed aspect
ratio), and that only video modes that evenly divide those numbers and
have the same aspect mode can be displayed properly - anything else will
have to be underscanned in one direction or another, and many modes have
to be dithered as well to get them to display at all. Sometimes the
mismatch is so severe that the display can't show a stable picture at all.

The only solutions are to accept that digital reality is quantitised or
to use an analog monitor.

--

T.E.D. ( XXXX@XXXXX.COM ) MST (Missouri University of Science and Technology)
used to be UMR (University of Missouri - Rolla).
 
 
 

"full-screen" DOS window doesn't fill screen

Post by ynotsso » Mon, 09 Jun 2008 14:30:02


Ted Davis < XXXX@XXXXX.COM > typed:


No, I'm not missing that fact. The aspect ratio on the working display is
1152/864 = 4/3 = 1.3333..., the same as on the 800/600 laptop display.
 
 
 

"full-screen" DOS window doesn't fill screen

Post by Ted Davi » Tue, 10 Jun 2008 01:05:07


The working DOS full screen is 640 x 480. 640 does not evenly divide 1152,
nor does 480 evenly divide 864 - the attempt to display 640 x 480 on 1152
x 864 necessarily results in siginificant compromises and approximations.

--

T.E.D. ( XXXX@XXXXX.COM ) MST (Missouri University of Science and Technology)
used to be UMR (University of Missouri - Rolla).
 
 
 

"full-screen" DOS window doesn't fill screen

Post by ynotsso » Tue, 10 Jun 2008 01:41:27


Ted Davis < XXXX@XXXXX.COM > typed:


640/480 = 4/3 = 1.3333..., the same aspect ratio. The DOS program displays
properly full-screen on the 1152x864 screen, contrary to your assertion.
 
 
 

"full-screen" DOS window doesn't fill screen

Post by ynotsso » Tue, 10 Jun 2008 01:46:04


Sjouke Burry < XXXX@XXXXX.COM > typed:


Thank you, that seems to make the most sense, but trying all the various FN
keys doesn't resolve the problem. I'll try to find the user's manual online
somewhere and refer to that. The manufacturer's web site seems terribly
convoluted.
 
 
 

"full-screen" DOS window doesn't fill screen

Post by V Gree » Tue, 10 Jun 2008 02:44:14


For IBM machines I have had in the past, there's a BIOS
setting named "Screen Expansion" that handles this issue.
Perhaps you have the same or similar.
 
 
 

"full-screen" DOS window doesn't fill screen

Post by 3c27 » Wed, 11 Jun 2008 00:29:17

Right click on the shortcut to the program and on the layout tab, change the
window size height to 25.
Louis



to
the
Raster
80x25.
 
 
 

"full-screen" DOS window doesn't fill screen

Post by ynotsso » Wed, 11 Jun 2008 04:59:17


3c273 < XXXX@XXXXX.COM > typed:


As mentioned in the OP, this is already done.
 
 
 

"full-screen" DOS window doesn't fill screen

Post by 3c27 » Wed, 11 Jun 2008 05:57:33

Oops, my bad.
Louis
 
 
 

"full-screen" DOS window doesn't fill screen

Post by ynotsso » Wed, 11 Jun 2008 07:05:42


V Green < XXXX@XXXXX.COM > typed:


Fabulous, thank you. The BIOS setting required was "LCD Display Stretch =
Enabled".
 
 
 

"full-screen" DOS window doesn't fill screen

Post by V Gree » Wed, 11 Jun 2008 09:26:10


You're welcome.

I knew I had seen that somewhere...'twas a good
test for my 50 year old brain to remember where.

Did enabling it have any other (adverse) effects on the
normal desktop, etc.?
 
 
 

"full-screen" DOS window doesn't fill screen

Post by ynotsso » Wed, 11 Jun 2008 09:47:50


V Green < XXXX@XXXXX.COM > typed:


None whatsoever. It was exactly what was needed.
 
 
 

"full-screen" DOS window doesn't fill screen

Post by Franc Zabk » Sat, 14 Jun 2008 15:08:50

On Sun, 08 Jun 2008 11:05:07 -0500, Ted Davis < XXXX@XXXXX.COM > put
finger to keyboard and composed:




I just tried full screen DOS mode on a Win98 socket 7 desktop PC with
a 15" 1024x768 LCD monitor (with an analogue interface).

For 80 cols x 25 rows, my LCD reports that my graphics card resolution
is 720x400. This would equate to a cell size of 9Hx16V. Allowing for a
single pixel between characters (have I got this right?), that would
mean a font size of 8Hx15V.

Doing the same for 80Cx50R, we get 720x400 resolution, a cell size of
9Hx8V, and a font size of 8Hx7V.

Again for 80Cx43R (mode co80,43), we get 640x350 resolution, 8x8 cell
size (with 6 pixels left over in the vertical direction), and a font
size of 7x7.

I obtained identical results on a 486 Win95 box when booted in real
DOS mode (different graphics chipset). I presume the fonts (and font
sizes) are hard coded into the video ROM BIOS of the graphics card.

Would it be possible to experiment with an external monitor that could
detect the resolution being output by the laptop's graphic subsystem?
Would that reflect the resolution being used by the internal display?

BTW, in Win98SE, the font size selected in a windowed DOS box (eg the
OP's 8x14) is ignored when switching to full screen mode. I have no
idea whether Win2K behaves the same way.

I suggest that the OP takes accurate measurements of the width and
height of a DOS text screen in full screen mode. Maybe the measured
aspect ratio will give a clue as to what is going on.

Could the OP's issue be addressed by means of a .cpi file?
http://www.yqcomputer.com/

Would command.com and cmd.exe produce different results?

- Franc Zabkar
--
Please remove one 'i' from my address when replying by email.