What is MSX-DOS 2?
MSX-DOS 2 is an operating system similar to the wellknown MS-DOS for IBM compatibles. It consists of a ROM with a kernel (including some BASIC-extensions) and the OS-files (COMMAND2.COM and MSXDOS2.SYS). On that disk there are also a lot of HELP files and some utilities. MSX-DOS 2 is in principle a severe extension to MSX-DOS 1.0x.
Can I use MSX-DOS 2 in MSX-BASIC too?
Yes. The DOS2 provides a set of CALL commands which makes it possible to handle directories from MSX-BASIC and create RAMDISK e.g.
Can I run MSX-DOS1.x software under DOS2?
The DOS2 is backward compatible, so DOS1 software should work, unless it tries to use Memory Mappers without DOS2's permission. It is recomended to run the MAP.COM utility made by Henrik Gilvad to prevent conflicts between DOS2 and old DOS1 or MSX-DISK BASIC v 1.x software which uses Memory Mappers.
[MAP.COM] [map.com ] - By Henrik Gilvad.
Does it support subdirectories?
It supports full directory access on both MS-DOS and MSX-DOS2 floppy disks.
What about the compatibility with MS-DOS disks?
There is only one minor difference between floppy disks formatted on a PC and an MSX. The boot sector on an MSX floppy disk contains different chunk of code due to hardware differences. Booting a PC floppy disk on an MSX will hang it. This will also happen on the emulators for PC. There is no further difference between the floppy disk formats! That means NO problems with exchanging files with PC compatibles! There's another small difference, though, MSX DOS 2 uses the FAT-back-up area to restore DELeted files, with the UNDEL command, so you don't have to remember these first charachters.
The 360KB (single sided) flopppy disks can also be read on a PC machine. But due to the media ID descriptor of an MSX 360KB disk is equal to PC's harddisk, PC will not recognise the MSX floppy disk. This can be fixed by changing the media ID code to the corresponding one on PC for a 360KB floppy disk. Download the CJS MSX2 emulator package and you will find there a program to change the media ID.
What will I get if I buy DOS2?
The DOS2 package contains:DOS2.x MegaROM cartridge and a floppy disk (720KB) with:
When is DOS2 needed?
Can I use DOS2 on MSX2 emulator?
Perhaps you allredy got the COMMAND2.COM & MSXDOS2.SYS files in your hands and tried to run them or boot with them on a MSX emulator without luck?
Here is the explanation why they they did not start up:
The DOS2 cartridge contains 64KB of ROM code. Without it the system will not work!
The CJS MSX2 emulator has an option which allows to run the DOS2 system. If you wish to run DOS2 on this MSX2 emulator then you will have to get a ROM image of the DOS2 cartridge and above mentioned system files. The ROM must be extracted from the cartridge by using a ROM copy programme on real MSX (look in the [.ROM] section). Then the 64KB file must be split into 4 parts (each 16KB big). However the CJS MSX2 emulator allready provides (DOS2) alike support without emulating DOS2 cartridge. It has it's own (not found on real msx machines) additional routines to handle directories and even use the PC's Harddisk/CD-ROM drive directly from MSX-BASIC. So the DOS2 ROM(s) are needed only when you want to run software which requires DOS2.
Can other msx emulators than CJS run DOS2?
I don't know if other emulators than CJS MSX2, support the DOS2 cartridge, but I think it will be implemented in the future versions of e.g. fMSX/VirtualMSX (if it isn't allready). I will notify here when I find another emulators capable of using DOS2.
How much RAM can DOS2 use?
DOS2 can handle up to 4096KB of MemoryMapped RAM per memory mapper. It means e.g.
that you can on an real MSX with 4MB RAM create a huge ramdisk (which is
especially suitable for copying files e.g.). Note that there will not be exactly
4096 kB possible then, because 32kB is needed for the DOS2 system itself. The
number of 4MB mentioned is the real maximum, because the number of 16k-segments
is given in an 8-bit byte... But it seems that DOS2 can handle more memory
mappers. For details, check the tech info, see below. So, appearantly, with DOS2
and other memory-management software (like
Memman) you can handle more RAM, and then
the real limit of memory is given by the number of RAM slots installed on the
machine. That is, if you have a 8-slot expander and a 4MB
memory expansion in each slot, you can use up to 32 MB RAM, and the ultimate
maximum is (theoretical) 64 MB, if all slots are expanded and have a 4MB RAM
Memory Mapper in them. But then, there's no space for ROMs... Conclusion: DOS2
can handle up to 64 MB of RAM, which is the maximum amount of RAM on any
MSX.
(Info re-updated by Marcel Delorme)
What do I need to run DOS2?
Is there other way to get DOS2 in my MSX, than buying the cartridge?
If you have an real MSX2/2+, then it is probably possible to build it inside (unless all slots in your computer are expanded). It can also be placed inside a SCC sound card. Contact your local MSX hardware specialist! And ofcourse, you can also buy a MSX Turbo R, which has MSX DOS 2.30 or 2.31 built-in!
Other ways to get MSX-DOS2:
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What's the newest version of the COMMAND2.COM file?
Since the Panasonic MSX-Turbo R A1GT (with DOS2 built in) was released, there were no updates from ASCII. The latest version was delivered with above mentioned computer. It's version was 2.31. Fortunately the CPU group made a patch, which will update your old system files to V2.41. Version 2.41 features lots of new functions and improvements. You can find the full list of improvements at CPU's web page). There is also a demo of the patch with all HELP files (in English and Dutch) for downloading. Everything works and can be tested (except execution of the files (it's disabled since it's only for evaluation)). he patch can be obtained from: Fokke Post, Waaiershoek 36, NL-8321 BH Urk, Holland. The price for foreigners is 35NLG (incl. mailing costs).
Where can I buy the DOS2 cartridge?
DOS2 cartridge is available through different MSX user clubs (you can find them in my bookmarks). The price is approx. 30USD.
Is there other way to access (sub)directories on MSX?
For those who do not have DOS2 and want to get access to directories, there is a Japanese utility available. I have not tested it yet but it should work fine. This program can be found on Lucky's Home Page, in the MSX section. But it seems that the URL is broken, though...
There is an operating system called MISIX written by SOLiD soft, which provides access to directories in similar way as DOS2 does (CD, MD, RD commands). It can be downloaded from The OS page of Novatec Group.
Where can I find technical info on DOS2?
You can download some very nice documents about programming in DOS2 here. They were sent to me by Cas Cremers. Actually I'm gonna have to put these docs online in HTML format once, but before that happens, you can already download them.