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"PM Sent!" messages (or, how to use the Private Message system)

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Copyright and other legal issues

We are here to discuss vintage computing, so discussing software, books, and other intellectual property that is on-topic is fine. We don't want people using these forums to discuss or enable copyright violations or other things that are against the law; whether you agree with the law or not is irrelevant. Do not use our resources for something that is legally or morally questionable.

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New user moderation

New users are directly moderated so that we can weed spammers out early. This means that for your first 10 posts you will have some delay before they are seen. We understand this can be disruptive to the flow of conversation and we try to keep up with our new user moderation duties to avoid undue inconvenience. Please do not make duplicate posts, extra posts to bump your post count, or ask the moderators to expedite this process; 10 moderated posts will go by quickly.

New users also have a smaller personal message inbox limit and are rate limited when sending PMs to other users.

Other suggestions
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Low Level Format XT Class Hard Drive

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    Low Level Format XT Class Hard Drive

    Adapted from a thread started by Lorne on January 14th, 2010:
    Unlike modern IDE hard drives where a low level format is discouraged or maybe not even possible, MFM hard drives often need to be low level formatted. Here is the brief how-to.
    Controller Support

    Many MFM controllers have a user accessible routine to low level format a hard drive. The routine is part of the ROM BIOS extension provided by the controller, and it can be started by using the DOS debug command.
    To get to the routine you need to know where in memory the ROM BIOS extension is, and the offset to the routine. The location of the ROM BIOS is not always in the same place - it depends on the individual controller, and the person who installed it might have set the base address to something non-standard. A common segment address to check is C800:0000.
    Assuming that your controller does have its ROM BIOS located at C800:0000 and it does have a built in route at offset 5, the following debug command will invoke it:
    Here are some entry points for well known cards:
    Adaptec ACB-2072 (ST412 RLL): G=C800:ccc
    :WD WD1002A-WX1 (ST412 MFM): G=C800:5
    Juko D16-X (IDE-XT, IDE-AT): G=C800:5
    IBM Advanced Diagnostics

    If you have a genuine IBM machine or a close compatible, then you can use the IBM Advanced Diagnostics disk to low level format your hard drive.
    From the main menu, here's how you navigate to the low level format functionality:
    • Option: RUN DIAGNOSTOC ROUTINES (Note that after some initial floppy activity, there is no screen/floppy activity for a while - be patient.)
    • Answer Yes to "Is there a monitor .." question
    • Answer Yes to "Is the list correct" question
    • Option: RUN TESTS ONE TIME
    • Option: 1 FIXED DISK ADAPTER

    Assembler code in Debug

    All of the XT class controllers have BIOS support for formatting their hard drive, even if there is not a user accessible program for running it. The routine is part of the INT 13 support for hard drives.
    From a usenet posting by Wally Bass years ago:
    The original IBM (Xebec) controller BIOS has no lowlevel formatting
    routine, and cannot be induced to low level format a disk with any
    debug command of the form G =C800:xx. On the other hand, the
    controller has a 'format drive' command, and this is supported via
    BIOS call INT 13h AH=7. For that call, you pass the desired interleave
    in AL, and you pass the starting track in CX and DH, and the drive
    number in DL, as for other INT 13h calls. Formatting the drive, then,
    can be done with something like
      a 100
      mov ax,707   <--format, interleave 7, which I think was the IBM/Xebec value
      mov cx,1     <--start at cyl 0, sector 1
      mov dx,80    <--head 0, drive 80 (if that's the drive you're formatting)
      int 13       <--invoke the BIOS routine
      int 3        <--return to debug (breakpoint interrupt
      <CR to get debug out of assemble mode>
      g            <--execute the routine that you just keyed in
    This will format the drive as a 10MB drive (4 heads, about 306
    sectors), with the original IBM controller. If you want some other
    format, you have a lot more work to do, and would probably be better
    off getting a new controller.
    Wally Bass
    Third Party Utilities

    Programs like the Mace Utilities, SpeedStor, and others can low level format these drives.
    [wiki]Category:How To[/wiki]

    Useful article
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