Help creating bootdisk

[el-half]

I am trying to boot my own program from a floppy (like a MS-DOS bootdisk) so I write a little x86 assembly program (a .com file) and use a program rawrite to write it to a floppy.
I supposed this would work because .com files are simply an image of the code (unlike .exe's).
But when I try booting my computer with that floppy it simply stops (or hangs) at the point where it tries booting the floppy.

[nihil]

Where is the boot sector? you don't say what OS you are using, but I would have expected to have to create a bootable floppy first. From what you have sais, all you have done is copied your program?

Cheers

[el-half]

Why should it matter what OS I'm using?
I don't want to create a bootable floppy with dos on it.
I want to make a bootable floppy with my own program (call it operating system if you like).

[nihil]

Ah! I understand

Can you try the floppy on a Win98 or ME machine, it may give you a message.............the OS you are using for your experiment is of interest, as that might help me have a go at it.

I was always under the impression that a boot disk had to be set up as "bootable" or it would not be read any further than the boot sector bit............I could be wrong of course.

Cheers

[el-half]

Yes, I have tried (win98), that's were it hanged.
I tried something else now, I used 'sys' to make a bootdisk and replaced command.com with a copy of my own program (hello world). Now it booted but it said to enter the path/name of a command interpretenter instead of running my program.

I wrote my program as an image the first time heh. Do I have to make a custom bootsector for the first 512 bytes and only after that write the program itself?

[muert0]

Maybe try changing it to bootable with cfdisk?

[nihil]

Hi,

It is a VERY long time since I wrote a startup/boot disk, but I believe that what you say is more or less true..............at least you have received a response, rather than an invalid media message

I would have thought that you would need some sort of command interpreter, otherwise how will it know how to execute your program.

I am basing that on Windows installation disks and the diagnostics installation disks that come with hard drives. I know that CDs use "autorun" or whatever but I have never investigated it.........way after my time.........I am an old fart remember

[el-half]

I would have thought that you would need some sort of command interpreter, otherwise how will it know how to execute your program.

How does it know how to execute that command interpretenter then?
The thing I tried the second time is defintly not what I want to try.

I actually want to write an OS (well, actually a program that boots like an OS, not an OS really).
How the hell do you boot it then (floppy)?

[nihil]

As I recall, they usually boot up to a command line prompt. Try creating a Win98 boot disk and check out what is on that.

I will have a look at some of my old boot disks and see what I find. I am wondering what you want to do once you have booted with this disk..............like load CD drvers or whatever?

Cheers

EDIT: This article deals with the missing command line interpreter:

http://www.computerhope.com/issues/ch000012.htm

OTHER INTERESTING LINKS:

http://www.bootdisk.com
http://www.startdisk.com
http://www.computerhope.com/boot.htm

[el-half]

http://www.computerhope.com/issues/ch000012.htm

Obviously, it thinks the command.com is corrupt here as I replaced it.

I don't want to do anything specific, I simply want to run a program without an operating system (making it an operating system itself...sort off...you know what I mean).