writing my own OS.....where to start from??
 

hi I wished to write a small OS, I would like to know if you know where to start, I've created my boot loader, but now I don't know what to write next... I'm not able to find any good src on the net......
thanks

loman

Probably something for the devices.

I read this page sometime last year, found it very interesting: hxxp://nocturnalnetwork.com/os.htm

Also, of some small interest: hxxp://www.linuxgazette.com/issue85/mahoney.html

Regards,
Satyric0n

About OS
 

Hi,
IMHO, a man who want to start (ehmmm, sorry 4 my english) writing his own OS need basic theory about scheduler, processes and threads , memory management, and so on...but maybe you already know this things.
Maybe you want to start writing an OS based on microkernel like L4 (very nice IMO :) ) ....
I am not an expert, i'm only a student but as you already know, writing an OS is not only a boot sector.
After that, you will know how, what and where to do something.
IMO.

PS.
Oh my god, this is my first post!

Try going to www.osdev.org, it links to a nice OS development resource centre which has lots of info.

Well here is a bit of info on the subject... hxxp://my.execpc.com/~geezer/osd/
alt.os.development would also be a good place to find more info

in my opinion the first and the most important thing to write OS is to know very very much about Memory Management, without good and nice memory management you canť write some nice kernel

but its very hard to work

Try reading source code of other O.S. such as LinuX,HURD,BSD
P.s.> reading iz a source of knowledge ! Soorrry for my bad english ;o))

Have look here, you may get something.....

http://www.cse.ogi.edu/class/cse526/Reading%20List.html


http://www.nondot.org/sabre/os/articles

http://www.memorymanagement.org

http://www.williamstallings.com/OS4e.html

Tutorial for OS writers :) (but in Russian :( ): hxxp://www.codenet.ru/progr/os/intro.php

If you interesting in "Realtime Operating Systems. Concepts and Implementation of Microkernels for Embedded Systems." by Dr. J��rgen Sauermann, Melanie Thelen, let me know. I'll send.

linux is a good example.

you should write some code switch to 32-bit model(in x86 pc).

i think you can find MSDOS source in internet, it will good work for u. because linux is full of difficulties which one is not good at it.
I found it is http://www.driverdevelop.com/dlit.php?id=272, but it require access. good lucky for u.

Actually, the DOS source is also on the FTP, if one has access, which loman should.

Regards,

You can see MenuetOS, a open source 32bit OS and free FASM source code.

MS-DOS 6.0 source code is released by Microsoft.

U can get it from www.microsoft.com

Look at this
http://www.reactos.com/

Search Around for "Bonifide OS Dev" they have a mass of sources and technical data that will help you get started :)

May be hxxp://oslib.sourceforge.net/ help you

Charm OS. I think it is a very good start point:

http://gryaznov.net/projects/list.php?p=chaos

I think linux source is best choice.

What type of OS do you want to write? What is the traget system? Intel CPU? MCU? Real Time OS?
It all depends on your goal. You need to clearly explain the details of your OS project.

Next step..
 

If you have the boot loader ready you can write a simple command interpreter.

Look OSKit project:
h**p://www.cs.utah.edu/flux/oskit/
h**p://www.nongnu.org/oskit/

I've seen MenuetOS also... I can't seem to get it to work, since my graphics are too advanced for it. I've tried everything, but it looks simple enough. Take a look at that, maybe it'll help you find a way to do certain things.

eCos
 

The embedded configurable operating system (ECOS)

http://ecos.sourceware.org

is worth a look.

heeh i don't know how advanced is your gfx but for me it works OK, ihave Geforce Ti4800SE ;o))

May be linux is a good choice. I try to read the sourcecode about linux,but it is very difficult for me. :rolleyes:

http://linux.ustc.edu.cn/~chyang/books/ulk2nd.pdf
http://www.nondot.org/sabre/os/articles

Crazy idea!
 

You would go crazy if you try to read the source of Linux, or BSD. It will take you couple months just to understand the low level code. Why not try to start with this books "linux kernel internal", then move up from there. I also have a book "Writing 32-bit OS" from Sams which have all the source in there too. PM me if you want the source.

Well, i haven't enough money to buy such bookz and stealing iznt good way ... when i started to lernt something about how o.s. works around year 1996.. there was not such books ... Btw>
thiz source code iz well documented and you shuldn't read whole source ;o)) ..

Sorry for my English ,iam only human ;o))

The best OS's I've seen for beginners are SteveOS and JeffOS...both are really easy c code on setting up the IDT, keyboard handlers, basic memory management/paging.

For something more serious, I really love ReactOS (I'm a developper in the team). It's an open-source clone of Windows NT and I'm sure in a couple of years will run more then 80% of Windows apps. The whole kernel is really enlightening to look at, and it works basically just like NT's.

Best regards,
Alex Ionescu
http://www.relsoft.net

This is the "write your own Operating System" OS-FAQ.
/http://mega-tokyo.com/osfaq2/

I must say that you are going on an adventure you'll never forget (if you stick to the path and dont run and hide.. ;) Writing your own OS is a challenge for most people. Have fun and dont bang your head against the keyboard to much. :p

Here are some links from me (warning some assembly needed :eek: :D )
hxxp://www.dynatos.org/
hxxp://board.win32asmcommunity.net/forumdisplay.php?s=&forumid=34