Transcript presentation source

1/20 Disk Boot
MIS-B200-01
Spring 99
Agenda for 1/20
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roll call
discussion of disk boot
discuss topics for group projects
discuss plans for Friday, 1/22/99
progress report
From the CD-ROM: Tour the
Disk Boot Process
Disk Boot, step 1: check the floppy
Step 1: The ROM
BIOS checks the
floppy drive for a
diskette with
system files.
These system files
are called
MSDOS.SYS &
IO.SYS.
?
step 1A: check the hard drive
Step 1A: If no
system files
are found on
the diskette,
the hard drive
is searched for
the files.
MSDOS.SYS?
IO.SYS?
step 2: load the Boot Record
Step 2: The boot
record is copied
to the RAM
address 7C00.
The ROM BIOS
gives control of
the startup to
this program.
Disk Boot, step 3: load the IO.SYS
Step 3: the Boot
Program copies
the IO.SYS file
into the RAM.
The Boot Record
now gives
control to the
IO.SYS.
step 3A: Inside IO.SYS
Step 3A: Part of
IO.SYS is
SYSINIT,
which leads
the rest of the
boot-up
process.
step 4: SYSINIT takes over
Step 4: SYSINIT
loads
MSDOS.SYS
into RAM,
which helps the
ROM BIOS to
run the
computer.
step 5: SYSINIT bosses MSDOS.SYS
Step 5: SYSINIT
tells MSDOS.SYS
to follow
CONFIG.SYS’s
instructions and
specifications.
step 6: SYSINIT continues.
Step 6: SYSINIT tells
MSDOS.SYS to
load
COMMAND.COM
which has 3 parts.
The first becomes
part of the
operating system
(OS).
step 7: COMMAND.COM cont.
Step 7: The second
part of
COMMAND.COM
details the DOS
commands. This
C:/ DIR = list contents
stays in RAM.
C:/ RUN = run a program
C:/ CD = change drive
step 8: COMMAND.COM finishes
Step 8:
COMMAND.COM
initializes an
AUTOEXEC.BAT,
which starts up
various programs
that the user has
specified.
Disk Boot, finished.
The computer is
now fully
booted up.
Group Topics:
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2
3
4
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3
5
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8
9
10
Floppy Drive
Hard Drive
Keyboard
3
Monitor
Mouse
Modem
Scanner
CD-ROM
1
1
1
1
2
2
2
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3
3
3
InkJet Printer
2
1
Laser Printer
1
2
For 1/22:
Read ch. 3: How an operating system controls
hardware
Last:
Progress Report