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Hey, are there any documents on creating your own bootloader, like what needs to be done and HOW it can be done?  I'd really like to start my own boot-strapper for my OS but I'm having troubles with these examples -- they don't really explain WHAT's being done in too well of detail.

there are plenty of documents around that explain the PC boot procedure.

machine loads mbr/bs at 0x7C00, you then decide what is active partition (if mbr) and load that mbr bootsector.

bootsector does whatever it wants. preferably, load the kernel...

Checkout my tutorial "Copying your bootsector to a floppy disk":
http://osdev.mega.net.kg/usingpcopy.htm

It will get you started on making a bootsector and you can download a very basic bootsector.

K.J.

Uhh... KJ -- thanks for the link but it didn't work...


Also, what's something good to search to find these documents?  I've tried things like "Creating a bootloader"  "Writing your own bootloader" "Making a bootloader"  "Developming a bootloader"  ( same for bootloader = bootstrapper )

Sorry, the server is down. You can get it here:
http://osanswers.port5.com/usingpcopy.htm

As for searching, try "bootsector" instead of "bootloader":
http://www.google.com/search?hl=en&ie=I ... bootsector

K.J.

Try searching with this: how to write your own operating system. You should get a few links that will lead to making a bootsector. When compiling the bootsector use this if using nasm as your assembler:

nasm boot.asm -o boot.bin

-o - outputs filename

copy it to floppy by downloading partcopy from

John fines website
http://www.execpc.com/~geezer/johnfine/index.htm

pcopy02.zip is the file to download
this is how you use it:

partcopy boot.bin 0 200 -f0

partcopy source source_offset length destination

boot.bin - source file
source offset - 0
length - 200
destination - -f0 = floppy drive (0)

I've started writing a tutorial on the subject myself, called, LoIS, but right now it's in only the earliest stages of preparation. Check back from time to time on it as I work on it. You can also see an example of a simple boot loader, which is being used as the basis for the LoIS code, in the thread titled "I Can't Believe I Finally Did It" on this very message board.

In the mean time, check out the Lucie Project's Bootloader Development Walkthrough, which covers much the same ground I intend to.

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