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  1. #1
    Join Date
    Oct 2001
    Posts
    87

    Cool what goes first???

    What are the files which are loaded first before the OS is loaded?
    Like I know command.com is loaded first, but is there a file which is loaded before that? And can somebody please tell me which file
    is loaded just before the win.com file is loaded?
    Thanks

  2. #2
    Join Date
    Jun 2002
    Location
    Letchworth, UK
    Posts
    1,020
    If you have a facility for examining disks, have a look at track 0 of your disk. Try a floppy to start with: you don't want to screw your hard disk by doing something silly. If you sys the floppy, it will install the bootstrap on it. The bootstrap is the first thing that is loaded and it lives somewhere on track 0. It then tells the machine what to do next.

    As for your other question, I don't know what is loaded between command.com and win.com. Probably nothing because once command.com is loaded, you can type win and windows will boot up.

    If you have a virus checker on, it may stop you examining track 0.
    Succinct is verbose for terse

  3. #3
    Join Date
    Oct 2001
    Posts
    87

    thanks

    hey thanks mate!!
    But can you tell me which utility to use to check for sector 0?

  4. #4
    Join Date
    Jun 2002
    Location
    Letchworth, UK
    Posts
    1,020
    I've normally written my own whenever I needed to look at sector 0. Use a 16-bit compiler in DOS and you won't go wrong. You can get Turbo C++ from the Borland museum

    Software Interrupt 13H
    Read a diskette sector
    AH=02H
    AL=number of sectors
    CH=track
    CL=sector
    DH=head
    DL=drive (1=a, 2=b)
    ES:BX = pointer to buffer

    Result CF=success/failure
    AL=status
    AH=sectors read

    Reading hard disks
    AH=0AH
    the rest of the registers are the same

    Have fun.
    Succinct is verbose for terse

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