Chapter 6: Disk Storage; Introduction - NCR PC4I Technical Reference

Chapter 6
Disk Storage
INTRODUCTION
Both flexible disks and fixed (Winchester or hard)
disks can serve as disk storage for the NCR PERSONAL
COMPUTER. Capacity of an internal fixed disk is 10
MB, standard diskette drives store data in 48 TPI
format.
A typical system includes either two flexible disk
drives or one flexible disk drive in conjunction with
a hard disk drive. You may alter your system by means
of the following kits:
3299-K702 - 48 TPI flexible disk drive
3299-K701 - 1.2 MB (96 TPI) flexible disk drive
3299-K705 - Controller and cables for 3299-K701
3299-K750 - Internal fixed disk drive
3282-1212 - External fixed disk drive
3299-K725 - Controller for fixed disk drives
K702 makes use of the flexible disk drive controller
incorporated in the system main processor board.
48 TPI FLEilBLE DISK DRIVE
The computer has one or two 5 1/4-inch flexible disk
drives integrated to provide mass storage of programs
and data. The drives contain read/write controller
electronics, driver mechanics, read/write heads, and
head positioning mechanisms. Systems with an
integrated fixed drive have only one integrated
flexible disk drive; this is mounted on the leftmost
side of the computer's front panel.
Flexible disk drives are connected in a daisy-chain
configuration. A DIP resistor module provides the
terminator in the last unit in the chain.
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