Transcript history of ms- dos

DISK OPERATING SYSTEM
•Is a master program that coordinates
the flow of information between the
computer and the user.
•A command user interface (text based)
•Has the responsibility of integrating the
various devices that makes up a
computer system.
MS DOS ENVIRONMENT
C:\My Documents\Hello.txt>
DRIVE
PATH
COMMAND
PROMPT
Responsibilities of DOS:
•Coordinates the input and output devices
•Enable user to load and execute programs
•Maintain an orderly system of files on disk
MS – DOS was known variously as :
•Seattle Computer Products 86-DOS
•IBM Personal Computer DOS
•Zenith Z-DOS
- developed by Seattle Computer Products
for its 8086-Based Computer
QDOS 0.10 (Quick and Dirty Operating System)
• first version of DOS in August 1980
•had all the basic utilities for assembly
language except an editor
EDLIN ( Editor of Lines)
•A primitive line-oriented
operating system
July 1981 – Microsoft bought all the rights to
DOS from Seattle Computer Products
HISTORY OF MS- DOS
Version
1.0
1.25
2.0
2.11
3.0
Date
Event
August 1981 -original version of DOS,
text-based, 16 bit, single
user, single tasking
August 1982 -support for double-sided
disk
March 1983 -support for 10MB hard
disk, directories and
double density 5.25” floppy
disk
1983
-support for foreign and
extended characters
1984
-32MB hard disk was
added
Version
Date
Event
3.1
1981
- network support was
added
3.3
April 1987
-support for high
density 3.5” floppy
disks. It has more than
one partition of hard
disk
4.0
July 1988
-support for partitions
on hard disk up to 2GB
and graphical shell. It
contains large number
of bugs.
4.01
November 1988 -bugs were fixed
Version
Date
Event
5.0
June 1991 -major upgrade. Allowed parts
of DOS to load itself in the high
memory area and device
drivers. Added support for
IBM’s new 2.88 MB floppy disks
6.0
August
1993
6.2
November -extra security, new disk
1993
checker was added
6.21
March
1994
-has an alternative
compression program
6.22
April 1994
-licensed a disk compression
called double disk
-added disk compression utility
(MS Backup Program)
Version
Date
Event
7.0
1995
7.1
1997
-be came a part of Windows 95
which support for long filenames
-support for FAT 32 Hard disks,
a more efficient way of storing
data on large drives
BOOTING A COMPUTER
The computer will go through a process of
“booting” or “bootstrapping.” The term comes
from the phrase “pulling yourself up by your
own bootstraps.”
With the power off, a computer is a dead hunk
of steel, silicon and wires. During the booting
process, it has to wake up, find all of its
peripherals and configure itself o run software.
Loading a computer follows a sequence to
make all this happen.
BOOTING A COMPUTER:
1. BIOS (Basic Input Output System)
•A series of instructions contained in a ROM ( Read
Only Memory)
2. POST ( Power On Self Test)
•The very first thing that happened to boot sequence.
It runs from the BIOS and allows the computer to
check the memory, keyboard, disk drives, etc.
3. MBR (Master Boot Record)
•When all the peripherals are working, the BIOS then
looks for the appropriate disk for further instructions.
Whether a floppy or hard disk, it contains the very
first sector of a bootable disk (the boot sector)
contains the MBR which contains the information on
where to go next in the boot process.
DOS BOOT SEQUENCE:
1. IO. SYS
•Contains the interface between MS-DOS and
the input/output subsystem. It allows the OS to
communicate with the basic peripherals and
perform input and output tasks.
2. MSDOS.SYS •Is the Kernel of the OS. It interacts
with the hardware and help process
the various DOS functions.
3. CONFIG.SYS •Contains the information that
configures the system
4. AUTOEXEC.BAT
•A batch file which means that it contains a
series of commands that are executed
whenever the file is run. “Automatically
executed” when you boot.
SUMMARY OF DOS BOOT
SEQUENCE:
1.POST
2.MBR
3.IO.SYS
4.MSDOS.SYS
5.CONFIG.SYS
6.COMMAND.COM
7.AUTOEXEC.BAT
8.COMMAND PROMPT