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TS9000/TS9050 TouchStar Systems User Manual
B - SYSTEM REFERENCE
is formatted, the arrays becomes a bootable drive accessible as a
normal DOS fixed disk (such as drive C:\). Standard start-up
files config.sys and autoexec.bat can be placed on the drive to
tailor the system configuration and automatically start applica-
tion programs. Any standard DOS application developed and
tested on floppy or hard disks can be moved onto the Flash drive
using standard DOS utilities and commands, such as copy, etc.
Real-Time Clock
The CMOS real time clock combines a complete time-of-day
clock and alarm with a one hundred year calendar and a
programmable periodic interrupt.
Battery Backup
An on-board, socket-mounted, Rayovac FB2325 H2 six volt
battery operates the clock and maintains RAM amount, video
adapter type and I/O device configuration information when
external electrical power is removed from the system. Citadel
recommends replacing the battery every 10 years.
Interrupt Controller
Hardware-level interrupts are used to support several of the
TouchStar system’s on-board I/O functions. The system control-
ler incorporates two programmable interrupt controllers that
are compatible with the Intel 82C59A. These controllers accept
requests from peripherals, resolve priority on both pending
interrupts and interrupts in service, issue interrupt requests to
the CPU, and provide a vector used by the CPU as an index to
determine which interrupt service routine to execute.
The controllers are addressed and cascaded in a manner com-
patible with the IBM AT. The Master controller is located at I/O
addresses 020
H
- 021
H
, while the Slave controller is located at
addresses 0A0
H
- 0A1
H
. The priority assignment modes can be
reconfigured at any time during system operation, allowing the
complete interrupt subsystem to be restructured, as needed.
