Something related to BIOS design using NASM (

[nobody]

Hi

thanks for all the help i have been given in this forum so far .Right now i am having some thing to discuss with you actualy i am looking to deign my own OS using NASM and GCC compiler and till now i m confused about BIOS thing i want a clear picture that can i develop my own bios or is it what you get with the mother board vendor .If this is so then what about designing something you call DOS intrrup can i do that?? because i dont want to use legacy intrrupt DOS left over the year as i said something new i m looking for and how about how will you differentiate between a Kernel and a BIOs is it the samething please help needed i am going through lots of material over the web and i m confused actualy so looking some suggestion from you guys hope you can understand my delima thanks please give me good sugestion so that i can start my work on it thanks again !!

[Frank Kotler]

BIOS design is a "beginner question"???

Well... the BIOS is something that "comes with the motherboard". They're mostly "flashable" these days, I think, so you could probably add your own code. I would strongly advise that you not do so!!!

You can replace the bios interrupts with your own code. Unless you're planning on a 16-bit OS, you'll *have* to do so! We "cli" before entering pmode. Before we can "sti", 32-bit code to handle interrupts must be in place!!!

If you're serious about OS design, put Nasm in cold storage and hit the books for a couple (?) years. Tannenbaum's "OS Design and Implementation" used to be the recommended starting point. Check news:alt.os.development and links you'll find there for the latest. It's a *big* subject. (I almost feel that it's "too late" - the hardware is moving so fast that if you haven't already got a solid background, you'll never catch up! But I'm an old geezer... maybe it looks different to a young'un. Hope so!!!)

If what you want is an "educational toy", now *that* might be a reasonable thing to do! There's a thread in news:comp.lang.asm.x86 currently looking at "512devos" (simple command processor - fits in a bootsector) which might interest you. Mike Gonta's aeBIOS might be worth looking at - possibly *using*. (a 32-bit extended bios in asm) I came across (somewhere) a thing called "nap.asm", which implements an OS in a bootsector. Two commands, "e" to enter hex, and "j" to jump to it. You can do *anything* with it you can do with *any* OS... just not as conveniently. :)

Maybe, to figure out where to start, we should consider where you want to go. What's going to be "special" about your OS, compared to ?

Best,
Frank

[nobody]

oopsss *shy*  sorry to put this one here in beginner corner .


yeah you seems correct its late by this time but will definately do it !!.


Thanks Frank!!

[nobody]

> i am looking to deign my own OS using NASM and GCC compiler

Possible, see ReactOS. Hint: OS development is __very__ __very__ __very__ __very__ __very__ __very__ __very__ __very__ __very__ __very__ __very__ __very__ __very__ __very__ __very__ __very__ __very__ __very__ __very__ __very__ __very__ __very__ __very__ __very__ __very__ __very__ __very__ __very__ __very__ __very__ __very__ __very__ __very__ __very__ __very__ __very__ __very__ __very__ __very__ __very__ __very__ __very__ __very__ __very__ __very__ __very__ __very__ __very__ __very__ __very__ __very__ __very__ __very__ __very__ __very__ __very__ __very__ hard :-(

From your question there is no doubt that you are a beginner, so you went into correct forum, but with an inappropriate idea :-(

> and till now i m confused about BIOS thing i want a clear picture that can i develop my own bios

YES, but it's not really useful to do so.

> or is it what you get with the mother board vendor

YES.

> then what about designing something you call DOS intrrup

DOS INT's don't exist outside of DOS. Want to start developing a DOS ? DON'T do it - fix up FreeDOS or RX-DOS instead ... or extend Dex's MidiDOS ;-)

Have you exact ideas about how the GUI of your OS will look like ? YES ? Then you started from the wrong side :-(