What exactly makes a floppy bootable for a PC?

[Chribba]

Hi!

I'm currently trying to learn things in a for me unfamiliar area of the computer world. I'm talking about the process of booting a computer and what really happens at that moment.

I've since some time learned and used the ability to boot from a floppy disk to do certain tasks like partitioning and formatting hard disks. Now I want to know more about what files are the critical ones that must reside on a bootable floopy disk. I 'm also wondering what version of DOS thats loaded when you boot from a floppy. What's the master boot record? OK, maybe the questions are to many to be answered here all at once so I stop there. Maybe someone can tip me of some URL where I can get indepth knowledge in the subject!

Christian Eriksson alias Chribba.

[Igor M]

Hi,

To make your floppy disk bootable you must have at least 3 files on it: IO.SYS, MSDOS.SYS, and COMMAND.COM. Of course your disk must have a boot record in the boot sector, but it's not exactly the file. It's the spectial little program that resides in the very first sector of floppy disk and makes job of booting the operational system. Boot record can be created by FORMAT A: /S command or by SYS A: command. The version of DOS is determined by the version of files mentioned above. Hard drives can be used not for DOS only but for other operating systems, so hard drive have Master Boot Record (MBR). When you create partitions on the hard drive, they can contain different operatinig systems, and each one of them has its own boot sector in the very first sector of its partition. MBR selects the partition of hard drive determined as active and upon booting starts the boor record of this partition, which in turn loads the operating system located on this partition. In the most cases operating system resides on the first partition of hard drive and is the only operating system, and the first partition of hard drive is the active one. MBR can be writen by the low level format utility or by non documented FDISK /MBR command. Of course this is only simlified description of the boot process. May be someone supply you with more detailed information.

Good luck, Igor M.

[jorge]

What version of Operating System?
You need use
VER
(Internal order) in the command line,
that report your active operating system version

[jorge]

What version of Operating System?
You need use
VER
(Internal order) in the command line,
that report your active operating system version