Questions tagged [ms-dos]

MS-DOS, the Microsoft Disk Operating System, its OEM-branded versions, and x86 DOS clones in general.

Filter by
Sorted by
Tagged with
27
votes
5answers
6k views

Why did the monsters have "infinite invisible pillars" of hitboxes vertically in all versions of the DOOM engine?

Even in the last version of the DOOM engine, v1.9, used for Final DOOM, there is this strange limitation in which all the monsters have an invisible, infinitely tall "pillar" above and ...
11
votes
3answers
2k views

Name of MS-DOS program that shows realtime update of light/dark map of whole planet

Years ago (circa 1996-1997 maybe?) I ran a MS-DOS program that showed a map of the whole earth, updated once a minute with the time, timezones, and light/dark areas of the planet, taking up the whole ...
15
votes
2answers
1k views

How to use "AND," "OR," and "XOR" modes for VGA Drawing

I've been trying to implement a blitter in MS-DOS, but before I do that I wanted to test the various graphics modes of the VGA graphics card. (I'm emulating using DOSBox.) According to this paper on ...
15
votes
4answers
2k views

Commodore Mouse not recognized by a Commodore PC30-III 286 machine

I have Commodore PC 30-III 286 machine with a serial port at the back labelled "mouse". If I plug my Commodore mouse 1900 serial mouse then execute mouse.com at the DOS prompt then I get the ...
1
vote
0answers
194 views

Looking for MS-DOS clip art (possibly Lotus 123?) [closed]

As a kid, I was given a 286 with 640k of RAM and a 20MB HDD, that had Lotus 123 and WordPerfect (v5?) installed. MS-DOS (v3 or v5) only - No Windows. As the machine was very limited, I tinkered and ...
25
votes
6answers
4k views

How did DOS games manage to have multiple background layers?

Seems like VGA only has one background layer, it appears to be a typical bitmap screen like most home computers of the 80s (Amstrad CPC, Commodore 64 etc.) where each pixel's color is stored in a ...
49
votes
6answers
8k views

Why did some old MS-DOS games lack the ability to exit them?

While playing around in DOSBox-X, I'm reminded of some DOS games which appear to entirely lack the ability to exit/quit/close them. One prime example of that is "Paratrooper" from 1982. I've ...
29
votes
2answers
5k views

Why does Windows 1.01 crash at the splash screen?

When Windows 1.01 is started under DOSBox, FreeDOS or one of the later versions of MS-DOS, garbage characters are printed on the screen right after displaying the Microsoft logo. Here’s an example in ...
16
votes
3answers
2k views

Why can't I invoke the next interrupt service by incrementing the AX register after calling the same interrupt?

I have two snippets of 8086 assembly code, both of which are supposed to do the same thing: make the mouse appear on the screen. Show_Mouse: push ax mov ax,0 ;Reset Mouse int 33h ...
15
votes
7answers
5k views

Are there any good, non-abandoned PC emulators?

Mission: I'm trying to simulate a classic ~286/386/486/Pentium inside my modern PC (running Windows 10) in the most authentic way possible. Just a quick note to say that I (Sarah Walker) have decided ...
5
votes
1answer
335 views

Why does the ‘Get Next Selector Increment Value’ DPMI call exist?

In DPMI, interrupt 0x31 services 0x0000 and 0x0100 are capable of simultaneously allocating multiple protected-mode selectors in a single call. When that happens, both services return only the first ...
19
votes
2answers
2k views

How can I access the VGA card's ROM fonts with interrupt 10h operation 1130h in protected mode C?

I'm using Open Watcom 1.9 to write some 286 real mode, and 386 protected mode software for DOS in C. In real mode, I can retrieve a pointer to the system ROM character bitmaps in real mode using int ...
25
votes
1answer
4k views

Did the original MS-DOS Quake not have a menu item for freelook, and if so, why?

I know that Quake (the 1996 MS-DOS game) is a "full" 3D engine, and always had some kind of mouse support. However, even the original Wolfenstein 3D from 1992 also had mouse support from the ...
7
votes
2answers
394 views

Monitor can't display boot/DOS video mode making dual boot impossible

I have an HP ZR24w monitor connected via HDMI input to a newer custom machine running Win7, and via VGA input to an older Micron machine running Win98SE. I use the monitor's "source" setting ...
5
votes
1answer
288 views

How can I output a blank line from a batch file on the Atari Portfolio?

I'm am trying to make a batch script on the Atari Portfolio which uses DIP DOS 2.11 (pretty similar to MS-DOS 2.11). I need to put a blank line in my file and it won't work. I have tried echo., echo/, ...
16
votes
1answer
840 views

Why can MS-DOS not read partitions starting at logical sector 0?

When creating a FAT file system, mtools and newer versions of mkfs.fat write a stub MBR partition table to the boot sector. This makes the file system accessible when written directly to media that ...
5
votes
1answer
594 views

Which MS-DOS program implemented the "Methinks it is like a weasel" evolutionary algorithm?

In the late 1980s I had a set of 3.5″ floppy disks which contained some games like Sleuth, Centipede, Space War, and Sopwith. Also present was a program that I think was called "weasel", ...
6
votes
1answer
339 views

Is there any public documentation of the LapLink protocol?

Is the protocol used by the DOS Laplink software publicly documented? I seem to remember there were Linux tools that could use it. I cannot find anything useful on their website.
9
votes
5answers
1k views

DOS serial printer formats

Assume a DOS machine with a serial cable, and a selection of one of Epson FX-80, HP LaserJet, IBM Proprinter. At the other end of the serial cable is a modern machine, e.g. running Linux. On the DOS ...
3
votes
2answers
207 views

PS/2 Keyboard not working on Windows 95 and MS-DOS

I received a Packard Bell Multimedia 550 and it came with Windows 95. The problem is that keyboard input was not coming through. Before it attempts to boot into Windows 95, it shows the safemode ...
9
votes
1answer
674 views

What's the easiest way to change from MS-DOS 6.22 to DR-DOS?

I am trying to find a way to do task-switching/swapping (not necessarily multi-tasking) in a DOS environment. I have tried DesqView under DOS 6.22 but I don't have any real success. I hear that DR-DOS ...
7
votes
0answers
282 views

What are the differences between MS-DOS and DR DOS FASTOPEN?

OS/2 Museum's history of DOS mentions the FASTOPEN.EXE TSR was introduced in DOS 3.3. Its entry on DOS 4.0 adds some implementation details. It reminded me of the DR DOS FASTOPEN=nnnnn directive in ...
14
votes
2answers
801 views

How much of the Program Segment Prefix area can be reused by programs with impunity?

I am writing a tiny TSR program, and I want it to take as little memory while installed as possible. The memory footprint of every loaded DOS process, including a TSR, includes a data structure known ...
14
votes
3answers
2k views

Why did SMARTDRV have to be started with /x when DOS started?

In the default autoexec.bat for DOS 6.22, you see these lines: C:\DOS\SMARTDRV.EXE /X @ECHO OFF PROMPT $P$G PATH C:\DOS SET TEMP = C:\DOS According to this source, /X disables write-behind caching. ...
14
votes
1answer
420 views

Is there a way to cut idle CPU usage under Multitasking MS-DOS 4.0?

The operating system variously known as ‘Multitasking MS-DOS 4.0’ or ‘European MS-DOS’, to avoid confusion with the better-known single-tasking MS-DOS 4.0, has the mildly irritating flaw that it doesn’...
40
votes
3answers
8k views

How do DOS games like DOOM benefit from a PCI graphics card?

The original DOOM and its derivatives (DOOM II, Heretic, Hexen) were early 90s 3D games released at a time when DOS PCs usually had ISA bus Super VGA graphics cards. In the following few years, PCs ...
2
votes
1answer
277 views

Microsoft C 6, far pointer, cast to int, warning C4047

Trying to access one byte in memory using segment/offset, like this union REGS in, out; struct SEGS segs; int v; char _far* p; ... int86x(...,&in,&out,&segs); p = (segs.es << 16) + ...
10
votes
0answers
325 views

Assembler where output file was executable WHILE including the source code

I seem to remember using an assembler with the following interesting workflow: You'd write an assembly language file and assemble it. The output overwrote your source code by placing the executable ...
30
votes
3answers
3k views

How can I play QBasic Nibbles on a modern machine?

MS-DOS versions 5 and 6 come bundled with the QBasic interpreter and a handful of example programs written in that BASIC dialect. One of the programs is Nibbles, a variant of the well-known Snake game....
5
votes
2answers
616 views

How 3Dfx Voodoo 1 Emulator works

reading of this question brings up 3Dfx Voodoo 1 Emulator in my memories. I always wandered how did it work so good time as any to ask... My memory is hazy on the details so I might miss remember ...
12
votes
6answers
5k views

How can I tell whether a DOS-looking exe. requires a 32-bit CPU to run?

Is there some simple method for determining if a DOS (or OS/2, or Windows etc.) binary (.exe or .dll) is 16-bit or 32-bit? The Linux file command just says "executable". I want to ...
4
votes
1answer
339 views

Use a USB mouse for DOS games

I have a Thinkpad T41 on which I installed Windows 98 SE. I installed an old DOS game, and was wondering if I could get a USB mouse to work with it ? (the PC doesn't have a PS/2 port) At the moment, ...
5
votes
2answers
209 views

How to get Terminate running in DOSEMU on recent machines? [duplicate]

When trying to run http://www.terminate.com/ under http://www.dosemu.org/, I get Runtime Error 200. I know that this is a well known issue with software compiled with Turbo / Borland Pascal and using ...
28
votes
5answers
4k views

What really is a sound card driver in MS-DOS?

To my knowledge, neither MS-DOS nor BIOS offers any kind of API for sound cards. Therefore the concept of a "driver" is absent, as we know it today. Apart from accessories and sample files ...
-1
votes
1answer
302 views

How were console games ported to DOS?

Many popular DOS games were ported from video game consoles: Earthworm Jim Mega Man The Lion King The Lost Vikings Turrican 2 Rayman Oscar Zool Video game consoles generally have wildly different ...
12
votes
6answers
722 views

What software used Turbo Vision back in its prime time?

Turbo Vision, Borland’s text-mode widget toolkit, is fairly widely known by those old enough to remember it, and apparently quite influential: it gave rise to a number of ports and reimplementations (...
23
votes
3answers
12k views

Why was "C:" chosen for the first hard drive partition?

I was reading this answer, as the question came to my mind: why does C: indicate the first hard drive partition? The usage dates back to CP/M (as noted in a comment), was embraced by MS-DOS, and ...
2
votes
1answer
396 views

How to remove Virus:DOS/V_Sign from a DOS 6.22 system

Fresh install of dos 6.22, unfortunately there appears to be a virus in MBR, each time I get Virus:DOS/V_Sign when re-using floppy from this machine. I can't connect HDD to modern PC, any idea how I ...
12
votes
1answer
876 views

Difference between INT 0x20 and INT 0x21 (0x4C)?

Checking the MS-DOS interrupt list we see INT 0x20 "Terminate the program" (see https://en.wikipedia.org/wiki/DOS_API) but if we check the same page we see INT 0x21 with function 0x4C will &...
3
votes
1answer
269 views

Does there exist a MPU-401 to OPL3 TSR for MS-DOS?

There are a few games for MS-DOS with music only through MPU-401, like the platformer Abuse and the RPG Avalon. Is there a TSR available that intercepts MPU-401 port accesses and transforms them into ...
7
votes
1answer
523 views

SSH for DOS / Win 3.1

Is there an SSH client for DOS 6.22 or Windows 3.1 that supports certificates and could be used to connect to AWS or Azure instances, or any other server for that matter? I have another laptop ...
2
votes
2answers
1k views

Why does changing a DOS/Windows EXE cause it to not run? [closed]

If I hex-edit an EXE for DOS or Windows, by adding or removing some text for example, it will no longer run. If I just change a single char around to a different one, it may run. Is this some anti-...
10
votes
3answers
653 views

How can I boot or extract files from an IBM PS/1 with a DoubleSpace-compressed hard drive?

I’m trying to boot an old IBM PS/1, mostly with the intention to read out its hard disk. I realized quickly that the original floppy disk drive was broken, so I replaced it with a Gotek floppy ...
26
votes
3answers
6k views

Why does DOS ask for the current date and time upon booting?

In most versions of DOS, when they are started from a medium that lacks an AUTOEXEC.BAT file, the very first thing COMMAND.COM does is ask the user to confirm the current date and time: Starting PC ...
8
votes
5answers
2k views

Any tools (that actually work) for viewing PDF files in FreeDOS?

I recently installed FreeDOS on an old laptop and then transferred some dosbox based GOG games I own to the FreeDOS installation. The problem is the manuals for these games is in PDF format and I ...
2
votes
2answers
227 views

Why isn't this invocation of XMS function Move EMB 0Bh in Turbo C correct?

Following on from my last question, I cannot get Move Extended Memory Block (Function 0Bh) working in Turbo C 2.01. The following main.c contains only the minimum functions: get the XMS driver pointer,...
8
votes
2answers
669 views

How can I malloc() a block that's guaranteed to lie within a single DMA segment in Turbo C 2.01?

I'm following root42's videos about DOS programming using Turbo C 2.01. I've written my own Soundblaster 1.xx driver following the Creative Labs documentation, and I'm confused about memory allocation....
16
votes
2answers
1k views

Emulate a text-mode DOS program using a Unix terminal

Is it possible to run a text-mode DOS program in an emulator under a Unix-like operating system (Linux/*BSD/macOS) such that DOS text-mode input and output is done on a Unix terminal instead of a ...
9
votes
3answers
2k views

What did the SELECT command do in DOS?

The introduction to Greg Harvey’s DOS for Dummies: Quick Reference (also subtitled Command Reference in the first edition) contains this passage: This book not only gives you the lowdown on each and ...

1
2 3 4 5