flat assembler
Message board for the users of flat assembler.

Index > OS Construction > Boatloader...

Thread Post new topic Reply to topic

Joined: 22 Dec 2003
Posts: 139
joachim_neu 24 Dec 2003, 19:52

what has a bootloader to do??? What name has the file to have???


EDIT: Ah sorry, I haven't seen the other threat.
Post 24 Dec 2003, 19:52
View user's profile Send private message Visit poster's website Reply with quote

Joined: 18 Jan 2004
Posts: 97
Bitdog 07 Feb 2004, 17:51
BOOT.BIN is a 512 byte file that sits in the first sector of a floppy drive.
(Hard drive has a boot loader, but I'll stick with floppy stuff here)
Boot.bin is handed control of the computer after BIO does it's initial post
hardware checks/setup & memory installations for some interrupts n stuff.
You never see the file boot.bin for it has no name unless you save it to a file. It just sits at the beginning of the boot disk.


has a reader and writer for floppy A:
so format a floppy disk in DOS
format drive A: Unconditionally and install the Systems files.
Makes a bootable disk. Then run BOOTREAD.COM and the file
boot.bin appears in your directory.
It's the boot loader that loads the kernel.bin which is the opperateing system
you know as command.com ?
(I'm probably wrong about all this, but it's a start for you anyway.)
You can run boot.bin through a debugger or disassembler to figgure out
what it does. There are many code examples available on the internet.
Once you write your own boot.bin & kernel.bin
you can use BOOTWRIT.COM to write it to the beginning of floppy A:
then copy in kernel.bin and boot to it. Your new
HelloWurld-OS is a contender..........

Any way, my HowdyWurld-OS first saw the light of day last week
so now I'm an expert....Smile

Gud luk...
Post 07 Feb 2004, 17:51
View user's profile Send private message Reply with quote

Joined: 30 Jan 2004
Posts: 14
mastermind 07 Feb 2004, 18:46

Here's a useful loader: http://board.flatassembler.net/topic.php?t=941.


Install: Use Bitdog's bootwrit.com program or debug.exe.

I am...
the Mastermind!
Post 07 Feb 2004, 18:46
View user's profile Send private message Reply with quote

Joined: 04 Oct 2003
Posts: 86
Ralph 09 Feb 2004, 23:01
Heh, yah you are pretty much all wrong. The boot sector is simply the first sector on any bootable device. What it does and how it does it is up to the developers, but usually it enables protected mode and loads the rest of the OS somehow. Here's a good example of one:
Post 09 Feb 2004, 23:01
View user's profile Send private message Reply with quote
Display posts from previous:
Post new topic Reply to topic

Jump to:  

< Last Thread | Next Thread >
Forum Rules:
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum

Copyright © 1999-2024, Tomasz Grysztar. Also on GitHub, YouTube.

Website powered by rwasa.