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Open Source OS that Uses BIOS for Drive Access?

Posted by Cliff on from the is-DOS-the-only-one dept.

Int13 asks: "I noticed a question in a review of a book on RAID controllers: 'Why, the author asks, do makers of controller cards put all their BIOS utilities on DOS floppies which require us to find a DOS boot disk?' The reason for this is actually very simple. DOS is one of the few mainstream operating systems that will ALWAYS boot on a PC from any supported boot device, and it doesn't require any special disk drivers at all to accomplish this task or to support any file system that has BIOS support. RAID controllers always supply BIOS support, usually in an extension ROM. This leads directly to the question: Are there any other alternative open source operating systems that will do the same? (no, not Open DOS, since it's just a DOS clone)"

"Why can't Linux use a virtual x86 box to call INT 13h when there is no driver for a particular drive type? It would also have to play nice with the BIOS data area and extended BIOS data area and respect the top of low memory, but that's only a few kilobytes at most. Then people probably wouldn't need a DOS boot disk anymore. If such a thing already exists, is there some reason the install disks for most distros don't support it?

(Before anyone tries to claim that Linux plays nice with the extended BIOS data area and the top of low memory, I can tell you from personal experience that it definitely does not, at least not by default).

2 of 46 comments (clear)

  1. This isn't the interesting question to ask. by xyzzy · · Score: 2, Insightful

    The real question is: how long before these clowns get real and realize that the floppy drive is GOING AWAY -- I mean, seriously, most BIOSes are bigger than 1.44mb now! It's silly to still be manacled to this outdated, ridiculous technology.

    1. Re:This isn't the interesting question to ask. by walt-sjc · · Score: 2, Insightful

      Bootable CD's emulate floppies. That's how they work. The BIOS looks for a signature on the CD and if present, makes it look like a floppy. Of course, you can only use a floppies worth of information on that CD (I think 2.88M anyway) but that's enough to load drivers to access the rest of the CD in any case.

      Some boot loaders such as GRUB which DO use INT 13 actually do quite a bit. They are almost as much (and maybe more so) of an OS than DOS was, and are quite small.
      GRUB may actually be a good replacement for DOS for BIOS updates, etc.

      Hey, it's open source. Play with it. Modify it to suit your application / needs. Whatever.