ms dos

DOS (Disk Operating System)

In July 1980 IBM assigned Microsoft to develop a 16-bit operating system for the personal computer for the fee of 186,000 dollars. Although the company Digital Research of Gary Kildall allready had with CP/M 86 such a 16-bit version,but by circumstances no contract has been established with IBM. Microsoft did not have yet any operating system, Microsoft licensed CP/M from Digital Research in November 1977 for 50,000 dollars. Since Microsoft could not sell licenses, a corresponding agreement with the company Seattle Computer Products was reached for QDOS. QDOS is a 16-bit clone of CP/M and was finished by Tim Paterson in April 1980. At first Microsoft licensed QDOS for 25,000 dollars. After a licence agreement with IBM was signed, Bill Gates bought QDOS for 50,000 dollars in July 1981. How proved this was a very lucrative business. IBM delivered it on all IBM computers as PC DOS for the first time on the IBM 5150 PC, for all other ones the name MS-DOS was for OEM partner. MS DOS 1.0 consists of about 4,000 lines assembler code.

The command interpreter is integrated in the file command.com with the internal commands for MS-DOS. Together with the file io.sys for simple device routines like the access to the monitor, keyboard, fixed storage disks and interfaces as well as the booting code these form the base operating system. DOS works very hardware near.

MS-DOS was wide spread in 1982 when 50 companies licensed MS-DOS. Software and hardware manufacturers build on this binary standard at this time. In 1983, the success of the PC system was clear the desire for a graphical surface was rising. Microsoft corresponded to the trend and announced a graphical user interface named Windows in 1983. Many other systems lost her market relevance at this time. In 1984 the number of PC and MS-DOS resellers increased to over 200. IBM published the AT computer in August, this one should refine the market for personal computer with MS-DOS 3.0/3.1. MS-DOS is already spread worldwide on Intel x86 computers in 1985. The easy extendibility of the computer by numerous plug-in cards of third party manufacturers, relatively low acquisition costs and a strongly growing amount of applications was a reason for it.

1988 was MS-DOS established and had reached measured on the market share a monopoly in the DOS market. The number of the MS-DOS installations grew worldwide to about 60 million and surpassed all other systems with that amount. Almost every software company offered standard applications like word processing, calculation or also special solutions like measurement tools, CAD (Computer Aided Design) or image processing for MS-DOS. The PC manufacturers designed her systems compatible to MS-DOS except for few manufacturers.

MS-DOS 5.0 allows the use of the High Memory and Upper Memory Area for DOS itself, TSR programs and drivers. The most important new external commands in this version are DOSKEY, DOSSHELL, EDIT, EMM386 and LOADHIGH. UNDELETE can recover deleted files, UNFORMAT can undo the format of floppy disks. 2.88 mb floppy disk drives from IBM are now supported. The BASIC interpreter was improved in detail.

Update: With the release of Windows 95 up to Windows ME MS-DOS has only a minory roll. It is installed for compatibility reasons for MS-DOS programs and makes Windows 95 up to ME start able. DOS programs being executed in the DOS box or directly in MS DOS before Windows start. Today it finds application for boot disks or similar purposes.

Small reference of internal DOS commands

del, erase - delete files
rd, rmdir - delete directories
dir - show content of directories
cd, chdir - change current directory
cls - clear the screen
md, mkdir - create a directory
copy - copy of one or several files
ren, rename - rename of files or directories
type - shows the content of text files
set - shows the DOS environment variables or defines a new one
ver - shows the DOS version number
vol - shows the name of the storage drive

Small reference of external DOS commands

attrib - shows the attributes of files or set one of those
fdisk - partitioning or modify of the hard disk
move - move of files
mem - shows the occupancy of working memory
tree - shows the directory structure
format - format of storage drives

Field of Application
- booting system for storage media
- File management
- For single user systems only
- Network client (NetBEUI, IPX/SPX, TCP/IP)
- batch processing

Structure information
- 16-bit operating system, (formerly 8-bit)
- Single tasking
- command interpreter for internal and external commands
- external driver software imbedding for periphery devices possible

System environment
- minimum: 512 kbytes RAM, 5 mbyte harddisk storage (depends on version for full installation)
- FAT file system
- executable with every x86 compatible CPU
- low RAM and fixed storage disk needs

Page created: 2004-04-03 [SB]
Last update: 2009-01-21

Screenshots

MS-DOS 2.11	MS-DOS 5.0 Installation	MS-DOS 5.0 Settings	MS-DOS 5.0 Options with Shell
MS-DOS 5.0 prepare of hard disk	MS-DOS 5.0 Copying process	MS-DOS 5.0 Completion of the installation	MS-DOS 5.0 DOS-Shell
MS-DOS 5.0 DOS-Shell with version	MS-DOS 5.0 command line

Versions

Date	Version
1981 Aug.	MS-DOS 1.0, formerly QDOS/86-DOS, can use at maximum 128 kbyte RAM, FAT established
1981 Juni	MS-DOS 1.10,
1982 Aug.	MS-DOS 1.25, support for double-density floppy disks
1983 March	MS-DOS 2.0, support for IBM 10 mbyte harddisk, directorys and DD 5.25" floppy disk drives with up to 360 kbyte
1983 Dec.	MS-DOS 2.11, extended character sets
1984 Aug.	MS-DOS 3.0, support for high density floppy disk drives with 1.2 mbyte and harddisk devices with 32 mbyte capacity
1984	MS-DOS 3.1, first tiem with network support
1985	MS-DOS 3.2
1985	MS-DOS 3.21
1987 April	MS-DOS 3.3, extended for IBM's PS/2 computer, supports now bigger 3.5" harddisk drives and floppy disk drives, multiple partitions, character sets for different languages
1988 Juli	MS-DOS 4.0, XMS support, partitions with up to 2 gbyte, graphical shell, bug fixes
1988 Nov.	MS-DOS 4.01, supports multiple partitions bigger than 32 mbyte, bug fixes
1991 June	MS-DOS 5.0, Major Release
1992	MS-DOS 5.0a, bug fixes for Undelete and Chkdsk
1993 Aug.	MS-DOS 6.0, Competition to Novell's DR-DOS 6, DoubleSpace, Anti-Virus program, Defrag, Move command, improved MSBACKUP and several boot configurations, memory optimizer MEMMAKER, DOS Shell is delivered separately on floppy disks
1993 Nov.	MS-DOS 6.2, DoubleSpace becomes incompatible to the previous version, Scandisk, improved of DISKCOPY and SmartDrive
1994 March	MS-DOS 6.21, because of law conflict with Stac Electronics DoubleSpace is removed from MS DOS
1994 May	MS-DOS 6.22, Microsoft licences double disk of VertiSoft Systems and designates it in DriveSpace, last official standalone version
1995 Aug.	MS-DOS 7.0, MS-DOS component for Windows 95, LFS support through VFAT, more DOS programs are delivered on the Setup CD-ROM in the "oldmsdos" directory
1996 Aug.	MS-DOS 7.10, MS-DOS component for Windows 95 B and higher, supports the first time FAT 32 harddisks
2000	MS-DOS 8.0, MS-DOS component for Windows ME, last MS-DOS version