OSDev.org

assuming assembler. what tools does one need to code up a new OS ?
as i said before if i did it i would be building it purely to do pro multitrack recording. ie: a very slim OS less than 10mb if possible.
i would not use C or C++ as i believe in the purity of assembler.
also assembler would be great for dsp functions in multitrack recording.
what are the recommended tools ? fasm operating under windows to build the OS ?
or some other tool.

First of all, it depends on your platform, mainly windows or linux.

nasm assmembler is available for windows and linux, yasm is another assembler being developed that is compliant to nasm standards but supports amd64.

You'll also need a linker. This links files together, and you're going to need more than one assembly file with your code inside. The linker i use, and so do a lot of others, is ld. This comes with binutils on linux. On windows its apart of the djgpp package set.

With the assembler/linker you've used to assemble/link your code not gets a 'kernel'. Assuming you want to test it, you'll need to put it on a bootable hd of your own or an easy option is a floppy disk or floppy disk image. The disk image would need mtools (linux) for this. Not sure what can be used under windows.

An emulator is very useful when you only have one development machine. It pretends to be a pc inside software on your pc. This means you're not restarting constantely every time you want to test the OS.
Vmware, virtualpc, bochs and simics are all emulators.

If you intend to be lazy like me and not bother writing the bootloader and get it from elsewhere, then grub (or lilo?) could be used to boot your os.

Moose

thanks. hmm kinda gets me thinking. why not just use linux basics and then build my application ? i wish linux had a visual compiler. thats fast like assembler. so that makes me ask why would someone do a brand new Os when linux kernel is available ?

Moose,
are you an OS developer?
i tot of developing an OS , a simple one, for my final year project.
any opinions??

Personally I use a combination of assembler and AspectC++...
I used to use nasm but now I'm switching to gas and gcc inline asm in order to be able to more easily integrate my assembly into C/C++ code and vice versa.
Also to make my code more uniform.
I used to be rather reluctant to use C++ but after I saw some C++ kernels I started considering using it. However as a Lisp programmer I was already spoilt by CLOS (Common Lisp Object System) and saw C++'s objects as rather primitive. But now because of the aspect extension I can actually use C++ and feel reasonably good about doing that.
My advice would be that use assembly where it is needed and don't mess up your code by optimising it on the lowest level. Good algorithms are more important for efficiency than low-level optimisation...
Of course writing is assembly can be fun because of all the control and possibilities it offers...

- Esa