If, as you said, most DOS games want 2.22 or 2.23, then this is more important:

Changes from Version 2.21 to 2.22 - MSCDEX now loads into UMA. If there is enough memory available, MSCDEX version 2.21 and ear […]
Show full quote

Changes from Version 2.21 to 2.22
- MSCDEX now loads into UMA. If there is enough memory available, MSCDEX version 2.21 and earlier can load into upper memory. MSCDEX version 2.21 and earlier require the load size of MSCDEX (which varies for different configurations) plus 48K of memory to load. The extra 48K of memory is added to ensure there is enough memory to load COMMAND.COM.
- MSCDEX version 2.22 checks to see if the driver is being loaded above 640K. If it is, MSCDEX does not add 48K to the initialization load size because it does not need to be concerned with the transient portion of COMMAND.COM.
- MSCDEX is no longer version dependent. If you are using MS-DOS 5.0 or 6.0, earlier version of MSCDEX require that you use SETVER.EXE to tell MSCDEX the MS-DOS version is 4.0.
- The /V switch now reports accurate memory statistics. Earlier versions of MSCDEX were not accurate.

Changes from Version 2.22 to 2.23
- MSCDEX version 2.22 erroneously assumes that files in a directory on a CD-ROM are sorted (collated by ASCII code value). Performing a file search could result in missed files if the files on the CD-ROM are not sorted. MSCDEX version 2.23 does not assume that the files are sorted but instead searches the entire directory and does not return a "File not found" error message unless the file does not actually exist.
- MSCDEX version 2.23 allows files and directory names to begin with an exclamation point (!), allowing EISA configuration files to be shipped on CD-ROMs.

BTW, here's my list of MSCDEX.EXE (not MSCDEXNT.EXE) replacements again.

MSCDEX Replacements
-------------------
1.) Artisoft - CDLANX - Workstation/server replacement for MSCDEX. File size: 2.68 kb; File date: 03-09-92. Download it at http://ftp.artisoft.com/artisoft/public/cdlanx.zip

2.) Artisoft - MXSUB - MSCDEX replacement program for workstations. File size: 4.40 kb; File date: 06-20-90. Download it at ftp://ftp.artisoft.com/artisoft/public/mxsub.zip

3.) Caldera/Novell - NWCDEX (Novell DOS 7?) - The main problem is that this driver takes up about 60k and takes a large amount of memory to install. Nevertheless, This is an incredible mscdex.exe replacement. As of the 11/16/94 update returns the same canonical path as MSCDEX; earlier revisions returned "Cdex. D:\path", where "D" is the CD-ROM drive letter. [url]http://www.caldera.com,[/url] http://jason-n3xt.org/dos/DOWNLOAD/NWCDEX.ZIP

4.) Corel - CORELCDX - returns canonical names of the form "\\D.\A.\path", where "D" is the CD-ROM drive letter and "A" appears to indicate the first physical CD-ROM drive.

5.) Microsoft - Windows95 (MSCDEX-replacement VxD - CDFS.VXD?) - returns "D:\path", even though the MS-DOS 7.00 MSCDEX behaves identically to older versions

6.) Sam Houston State University - SHSUCD - v1.4b - a FREE CD-ROM client/server, it can store CD images on a hard disk, and includes a TINY MSCDEX replacement that can talk to the drive across the network as though it were attached with MSCDEX. Supposedly works with DOS, Win, Win95, NT, and OS/2, and the server can run in an NT DOS VDM or on a standalone box. It uses only 11K RAM resident and can be unloaded. You can find it on the SIMTEL archive at ftp.cdrom.com in the simtelnet/cdrom directory, or at its homepage at http://www.shsu.edu/~csc_jhm/

7.) ??????? - MSCDEX - This driver takes up about 20-30k, which is about the same as the Microsoft version. Not recommended for use with Windows (98?) - Windows doesn't seem to enjoy accessing the CD-ROM drive when using it; it's quite a confusing problem and maybe it's only relative to certain systems. Download it at http://jason-n3xt.org/dos/DOWNLOAD/MSCDEX.ZIP

8.) ??????? - SUPERCDX - It is primarily designed to run multiple CD ROM drives in a machine; however, it boasts a speed improvement over MSCDEX. The people who make it had a BBS at one time: (512) 326-2754. More information at http://www.google.com/search?q=cache:gaM4ee83 … cement%22&hl=en

Great research, guys! Now if only there was a way to get the source for any of these (if it was written in something other than assembly), make them work with NT, and rock the house!

Hm. I thought I'd just found another one (FDCDEX, works with FreeDOS) until I discovered that it's really just SHSUCD in disguise.

SCSUCD comes with source code - unfortunately for you, it's all in assembly with a little C.

Of course, you could also always use a disassembler on the MSCDEX replacements you find.

I'm curious to know whether most of the actual functions for MSCDEXNT are in the kernel, or whether we can actually create a MSCDEXNT-replacement...

... what's our reasoning for creating one again?...

The reasoning is that MSCDEXNT [2.21] doesn't have many of the features later versions of MSCDEX [2.22 and 2.23] had and that games depend on.

Attempting to interest a few PSX emulator CD-ROM plugin authors in this project. I hope I raise the interest of one of them... 😀

*wonderz who might be watching*

Attempting how? Posting on random PSX boards? 😉

Snover wrote:

Attempting how? Posting on random PSX boards? 😉

Beats standing on a street corner and screaming about it. Not that I would know anything about that...

Snover wrote:

Attempting how? Posting on random PSX boards? 😉

Hell no!

I enjoy my MAME.net email address and use it to my advantage - it comes in handy... an emulator author sees an email from it, he thinks twice... 😀

But I emailed Pete Bernert, who's an acquaintance from the old PSEmuPro dayz when I frequented the #psemu IRC channel that the devs all hung out in. He still frequents the messageboards at Retrogames, and knows me. So we chatted. He thought SaPu might be able to help, if he is interested in it. Lord knows SaPu's done other strange projects... such as a Windows NT/2000/XP patch for Connectix Virtual Game Station, a MMX "emulator" for processors which are non-MMX... but he also wrote an excellent CD-ROM plugin for FPSE and PSEmu-standard PSX emulators, including one that uses MSCDEX commands. Pete's uses ASPI/IOCTL commands. Between the two, if anyone could do it, they could... if they want to...

Good news - Sapu is interested in helping with this project, provided time isn't of the essence.

What I'd like to start here is a list of games which need these additional Microsoft CD Extensions, etc. as found in the later versions of MSCDEX.EXE. Batter up...

1st thing talk to Vlad. I believe he *might* have documented the cases where floppies games work wheras their CD counterparts audio do not.

I'll do that.

FYI: Here's some more info about what didn't make it in. M$ claims it's because these modes require direct hardware access (which as you know is a pain in WinNT/2K/XP).

See here:
http://support.microsoft.com/default.aspx?sci … b;en-us;Q314106

"Microsoft CD-ROM Extensions (MSCDEX) functions 2, 3, 4, 5, 8, E, and F are not supported."

That would be these (thanks to SaPu):

About the 'unsupported' MSCDEX functions from the MS article, here is a list of what they are taken from the 'Ralf Brown' interr […]
Show full quote

About the 'unsupported' MSCDEX functions from the MS article, here is a list of what they are taken from the 'Ralf Brown' interrupt list:
INT 2F - AX = 1502h - GET COPYRIGHT FILE NAME
INT 2F - AX = 1503h - GET ABSTRACT FILE NAME
INT 2F - AX = 1504h - GET BIBLIOGRAPHIC DOC FILE NAME
INT 2F - AX = 1505h - READ VTOC
INT 2F - AX = 1508h - ABSOLUTE DISK READ
INT 2F - AX = 150Eh - GET/SET VOLUME DESCRIPTOR PREFERENCE
INT 2F - AX = 150Fh - GET DIRECTORY ENTRY

It would be nice to be able to mount images (iso, nrg, etc.) directly without having to go through ASPI. Most games use the CD for speech, and they harass the poor drives unless they happen to be 1x. I think DosBox could use this as well. 😀

I can probably take a look at the MSCDEX specs -- I'm really pissed at not being able to play the CD version of Loom under Windows without destroying my drive and a couple of CD-R's (to get the lead-in right).

V.

Check your private messages.

DosFreak wrote:

oh the DOS MSCDEX is quite a bit bigger than the NT counterpart. 24kb as opposed to less than 1kb. 😮

Not relevant. 😀 MSCDEXNT does most of the work in Win32 (via NTVDM.EXE), so it doesn't show in the 16-bit code (causes traps and Win32 takes over from there).

V.

then what about VCDEX.DLL? What does that do? If it's pure NTVDM, then this may not be possible to work around...

vladr wrote:

Not relevant. 😀 MSCDEXNT does most of the work in Win32 (via NTVDM.EXE), so it doesn't show in the 16-bit code (causes traps and Win32 takes over from there).

V.

Yep, was just commenting on that fact. 😉

It may not be worth it to get MSCDEX working properly under NT. Dosbox would be the best and easiest solution...but if a way could possibly be found for NT too in the process.....

I'm betting it could be done tho, look at VDMSound.....

Dude, how exactly would you propose DosBox does it? It would have to use *exact* CD images on the HDD or have direct access to CDs.

Snover wrote:

Dude, how exactly would you propose DosBox does it? It would have to use *exact* CD images on the HDD or have direct access to CDs.

Direct access is not likely in DosBox. So more like "rip your CD to .iso+.wav format and play it through DosBox" kind of approach, or with an optional, platform-dependent plugin that does the actual ioctl.

V.

How about rip it to ISO+OGG? 😀

Tell you one thing, though... Ogg Vorbis is in dire need of a --r3mix flag. (That's how I know I get true-to-ear sound.) 😀