Browse Prior Art Database

User Selectable Boot Process

IP.com Disclosure Number: IPCOM000114700D
Original Publication Date: 1995-Jan-01
Included in the Prior Art Database: 2005-Mar-29
Document File: 2 page(s) / 73K

Publishing Venue

IBM

Related People

Landry, J: AUTHOR [+3]

Abstract

Disclosed is a mechanism that allows the user to control the source of the boot device for Personal Computer Systems. The user can select the boot sequence from a list of IPL devices on the system such as hard disks, diskette drives and adapter cards.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 52% of the total text.

User Selectable Boot Process

      Disclosed is a mechanism that allows the user to control the
source of the boot device for Personal Computer Systems.  The user
can select the boot sequence from a list of IPL devices on the system
such as hard disks, diskette drives and adapter cards.

      The majority of PC systems sold today are based on the ISA bus
architecture which makes use of fixed boot sequence and static
resources allocated to each device in the system.  This works fine
until add-in cards are added to the system.  In that case, there is a
possibility of resource conflict from the adapter, or the user cannot
control the boot sequence from adapters that take over the bootstrap
vector.  Plug and Play system BIOS helps address the problems of
resource conflict and the bootstrap vector, but does not address the
issue of boot sequence control.

      The solution to the problem is to allow independent control of
the possible boot devices through the BIOS configuration utility.
Each
potential IPL device is identified during early POST and has
resources
assigned to it.  When the system is ready to boot the operating
system,
each device in the boot sequence list is checked in order, and if
enabled, the boot vector for that device is initiated.  If the boot
vector fails, then the system attempts to boot from the next device
in
the boot sequence list.  The following shows the boot order used for
the Personal Computer system in the configuration utility.
  1.  Diskette Drives
  2.  Adapter Cards (SCSI, etc)
  3.  Remote-IPL (Network Cards, etc)
  4.  Hard Disk Drives

      The Diskette Drives field in the utility controls what drives
(if any) are used in the boot sequence to load an OS from.  An
optional
CD-ROM would also appear in this class of devices (removable media)
that the user could select from.

      The Adapter Cards field in the utility controls how the adapter
cards that chain into the boot vector (INT 19) are given control to
boot from.  The utlity lists th...