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INT 13h,  00h (00)       Reset Fixed Disk/Diskette System                 all

    Resets the fixed disk or diskette controller and drive, forcing
    recalibration of the read/write head.

       Call with:     AH         00h
                      DL         Drive number

       Returns:       AH         Status of operation (See Service 01h)
                      CF         Set if error, cleared otherwise

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       Notes:         If DL is greater than or equal to 80h, the floppy
                      diskette controller is reset, and then the fixed
                      disk controller is reset. The status returned in AH
                      in this case is the status of the fixed disk; to get
                      the status of the floppy diskette controller,
                      examine memory location 0:441h.

                      If an error is reported by the disk BIOS routines,
                      use this service to reset the floppy and/or fixed
                      disk controllers, and retry the operation.

                      A fixed disk reset is executed only 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. Also diskette operations that require
                      the diskette motor to be on will call INT 15h,
                      Service 90 (Device Busy), with the type equal to
                      "Diskette Drive Motor Start" (Type = FDh). This
                      allows the system to perform another task while the
                      drive motor is waiting to get up to speed.