Installation guide

SCSI
The SCSI (Small Computer Systems Interface) differs from the previous interfaces
in that it is not dedicated only to hard disk interfacing. It will allow printers.
floppy drives and other devices to share a common interface. The SCSI interface
allows the computer to communicate with up to eight separate devices.
With
SCSI most of the drive control is designed into the drive. The SCSI bus
transfers bytes of infonnation in parallel rather than in serial form like the
ST506/ST412 and ESDI interfaces. The maximum data transfer rate is from 1.5
Megabytes/second to 4 Megabytes/second. This is equivalent to a 12
Megabit/ second to 32 Megabit/ second serial transfer rate.
SCSI is still in an evolutionary stage. Some computer manufacturers have
customized their SCSI interfaces for their systems. These two factors coupled
with the inherent complexity of the interface are the primary causes of
incompatibility with SCSI devices.
ONBOARD CONTROLLER
Drives with integrated controllers are allowing MiniScribe to maximize disk drive
performance while at the same time reduce the had drive subsystems overall cost.
size and power consumption. These drives also minimize compatibility issues
since the controller circuitry is imbedded on the drive.
Computer manufacturers are designing new computers with hard disk support
circuitry on their motherboards. With these newer systems it is possible to plug
the new drives with integrated controllers directly into the motherboard. Check
with MiniScribe for compatibility with these new computers.
Older XT and AT systems can utilize these new drives with a simple interface
board that plugs into the system bus (like a regular controller) and the appropriate
cable. The xr interface will handle two integrated XT style drives. The AT
interface is available in two versions. One version will control two integrated AT
style
drives while the other version will handle two floppy drives as well as the
two AT drives.
rnSTALLATIONSOFrWARE
Installation/partitioning software is sometimes necessary in AT systems when the
AT BIOS does not support the drive satisfactorily and/or their version of DOS does
not allow multiple DOS partitions without external drivers.
Installation/partitioning software
1
s function is quite Simple. It handles all I/O to
all partitions beyond the DOS boot partition. It does this with an external device
driver
that is loaded in at boot time. This device driver reads the drive
parameters from the boot area of the disk allowing partitions beyond the DOS
partition to escape the limitations of the BIOS drive type.
Installation software is generally compatible with current versions of MS-DOS and
PCODOS. As new versions of DOS become available it is usually necessary to obtain
the most current version of installation software.
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