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Int 13h, 0Dh            Alternate Disk Reset                       fixed disk

    Resets the fixed disk controller and drives, forcing recalibration
    of the read/write heads. This service can be performed on fixed
    disks only.

        Entry   AH = 0Dh
                DL = Drive number (Bit 7 must be set)

        Return  AH = Status of operation (See Service 01h)
                CF   Set if error, else cleared

    ------------------------------------------------------------------

    See Service 00h for a more generalized version of this service.

    A fixed disk reset is only executed if the value in DL is less
    than or equal to the last fixed disk on the system. That is, the
    lower 7 bits of DL should be less than or equal to the number of
    fixed disks.

    For the AT, XT-286, and PC Convertible, the BIOS executes Int 15h,
    Service 90h (Device Busy), for the diskette (Type = 01h) and the
    fixed disk (Type = 00h) prior to waiting for the interrupt. Int
    15h, Service 91h (Interrupt Complete), is executed upon
    completion.