OSDev.org

hi

i have worked with bootloader program and now i
want to code the next thing which is writting a
little kernel outside a boot loader, so i need your
guidance in following matters ...

1. how to write a little kernel outside bootloader
(any simple sample code ?)

2. how to make binary of this kernel file ?

3. how to move that binary on floppy so that boot
loader jumps to it and start executing kernel ?

4. what changes i need in my boot loader in order
to locate the kernel and jump on its starting
position ?

5. any other tip !

many thanks

suhmaamiar

Hi.

1) Write a simple 32 bit string printing code and test it. I dont know about your gdts and etc so it will be much more efficient if you write these code.

2) Since you have written your own loader, it is very likely that your are using plain bin, just compile kernel source to coff and a.out and then link with ld into plain binary with ld's map file.

3) Depends on your bootlader. Bootlader I am trying to implement uses fat12 file system, so I just copy any needed files onto a: drive with windows explorer. If you are not using a file system currently then you can use partcopy. Search on internet.

4) I cannot understand what exactly you mean. But: You need only change your file buffer (or wherever you copy it) and then change addresss that you jump onto.

5) Go on doing with your own bootloader... (Or better to say: struggling with your own bootloader...)

Good luck...

i suggest you get a look at the FAQ of this site (should be available through .:QuickLinkz:.), which should help you building your binary image and preparing your floppy ...