Article: Q75095
Product(s): Microsoft Disk Operating System
Version(s): MS-DOS:5.x,6.0,6.2,6.21,6.22
Operating System(s):
Keyword(s):
Last Modified: 17-DEC-2000
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The information in this article applies to:
- Microsoft MS-DOS operating system versions 5.0, 5.0a, 6.0, 6.2, 6.21, 6.22
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SYMPTOMS
========
After starting an AT&T 6300, MS-DOS uses only one line of the screen to
display commands such as DIR, TREE, and so on; however, the startup information
remains on the screen even after issuing the CLS command. In the other cases,
the system will hang at the DOS prompt after pressing ENTER a few times.
WORKAROUND
==========
To work around this problem, add the following line to the CONFIG.SYS file, or
use the debug script listed below.
device=ansi.sys /s
The same behavior occurs on AT&T 6310 machines.
MORE INFORMATION
================
The ANSI.SYS /S switch is an undocumented switch that will force the video to
display in 25-line mode. MS-DOS 5.0 or 6.0 relies on byte 40h:84h of the BIOS to
work in 43/30 line mode. The earlier version of MS-DOS did not use this byte.
The following is a short program to patch the BIOS area into having the 25
(actually 24, because it is is 0-based) value required for a CGA/MDA adapter.
At the DOS prompt, type "debug" (without the quotation marks).
You will then see the Debug prompt (a hyphen). Type the following, pressing ENTER
after each line:
Debug User
Response Input
-------- -----
C:\> debug
- n patch.com
- a
xxxx:xxxx mov ax,40
xxxx:xxxx mov es,ax
xxxx:xxxx es:
xxxx:xxxx mov byte ptr [84],18
xxxx:xxxx int 20
xxxx:xxxx <press ENTER>
<press ENTER>
- r cx
: d
- w
- q
This will create PATCH.COM, a file you can execute from the command prompt. If
the problem is resolved, put an entry to execute the PATCH.COM file in the
AUTOEXEC.BAT file.
Additional query words: 6.22 boot ATT att6300 scroll scrolling 5.00 5.00a 6.00 6.20
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Keywords :
Technology : kbMSDOSSearch kbMSDOS621 kbMSDOS622 kbMSDOS620 kbMSDOS600 kbMSDOS500 kbMSDOS500a
Version : MS-DOS:5.x,6.0,6.2,6.21,6.22
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