Specifications
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3.8 USING AT BUS CONTROLLER INTERFACED HARD DISK DRIVES
The Little Board/286 can be used with one or two hard disk drives connected by means of a
standard AT bus plug-in hard disk controller. These can be used instead of SCSI hard disk
drives, or along with SCSI drives. Included in the AT bus controller hard disk drive category are
drives which have embedded AT bus hard disk controllers -- referred to as AT Bus Attachment
(ATA) or Integrated Drive Electronics (IDE) drives -- interfaced by means of an Ampro
MiniModule/ATDisk adapter that provides the required buffering and other interface signals.
These can be used instead of SCSI hard disk drives, or along with SCSI drives. In DOS
applications, the total number of drives used (SCSI and AT bus controller interfaced) can be up
to eight under DR-DOS, or two, under PC-DOS or MS-DOS.
One advantage of using an ATA interface rather than SCSI for hard disk interfacing is that
operating systems or programs that talk directly to a standard AT compatible hard disk
controllers can successfully be used with a Little Board/286. This includes multitasking
operating systems such as Unix, Xenix, QNX, etc.
To configure the system for use with one or two ATA or AT bus hard disk controller interfaced
hard disk drives, several parameters must be set in the board's Configuration Memory, using the
Ampro SETUP utility. These parameters are outlined below. For detailed instructions on the
use of SETUP, refer to the program's description in Appendix A of this manual. When using the
setup program or other Ampro software utilities, ATA interfaced hard disk drives are referred to
as drives connected to an AT bus hard disk controller.
n Drive Characteristics -- the board's Configuration Memory contains the parameters which
specify the physical format of the each drive to be connected by means of an AT bus hard
disk controller (or ATA drives). Included are the total number of cylinders, number of
heads, cylinder to begin precompensation, landing zone cylinder number, and the number
of sectors per cylinder. These parameters are set using SETUP's drive definition options in
the first menu page of the Standard (CMOS) Setup.
Note
Do not set the data for these parameters if the drive is
connected via SCSI
n Drive Selection -- in addition to specifying the physical characteristics of each AT hard
disk controller (or ATA) interfaced hard disk drive, you must also specify how they are to
be used by the ROM-BIOS. This is done using the SETUP Extended SCSI and Hard Disk
Configuration menu (third menu page). Specify one or two AT hard disk controller (or
ATA) interfaced drives (defined in the above step) in the DOS disk map as DOS drives to
be installed by the ROM-BIOS at system boot time. Note that you can have up to four
drives total (depending on the type of DOS being used), and they can be a combination of
SCSI and AT hard disk controller (or ATA) interfaced drives.