PATCH OR REVISE SOFTWARE. —
Minicomputers have the option to allow you to
manually insert and make revisions to machine code or
insert revisions using external peripheral devices.
Patches or revisions to the software are written by
authorized personnel only. The patches or revisions are
entered using inspect and change routines or
equivalents using the controls, data entry, and data
display man/machine interface.
Mainframes
The mainframe computers used for tactical and
tactical support data systems use a number of units and
panels to control computer operations. Their
controlling devices offer more options to perform the
man/machine interface but their functions are the same.
CONFIGURE THE COMPUTER SYS-
TEM. —Mainframes are generally designed to work in
large systems. In addition to a number of peripherals,
they also work with major subsystems (display and
communications). The software is designed to manage
the computer and its resources based on the amount of
hardware. Most large mainframe computer systems use
two or more computers.
This gives the system the
capability to run in the event one of the computers goes
down with hardware problems. Therefore, it is very
important that you understand and know how to
configure the system for full and reduced
configurations. You accomplish this by knowing the
capabilities and limitations of the software based on the
quantity of hardware for your system and by ensuring
all controls and switches on the computer(s),
switchboard panels, and display and communication
subsystems are correctly set.
APPLY POWER. —Applying power to
mainframes also requires more than just turning on the
ON/OFF switch. First, you must ensure there is power
to the remote panel. Then at the unit itself, usually a
circuit breaker must be applied, then blower and logic
power. Indicators are usually provided for blower and
logic to show there is stable power. Power to a
mainframe is critical and you must ensure there is a
stable power source. In addition to the circuit breaker
protection, interrupts are generated if there are
abnormal power fluctuations in which case the
computer will shut itself down. Mainframes also use a
4-digit time meter to record the accumulated hours that
logic power has been applied, except when there is a
time meter for each module unit. Some mainframes
have a separate power controlling device devoted
entirely for power. It is usually on the front of the unit.
Figure 8-29 is an example of a panel of such a device.
It also monitors the temperature of the computer
set.
Mainframes are also equipped with a battle short
switch (also indicated on figure 8-29) and an audible
alarm to allow the computer to run even when the
temperature exceeds the normal allowable operating
temperature established by the manufacturer and to
indicate excessive temperature in the modules.
USE CONTROLS, DATA ENTRY, AND DATA
DISPLAY. —Mainframes will use operator,
maintenance panels, and/or display control
consoles/units located near the unit. For our example,
Figure 8-29.—Example of the panel of a power controlling device.
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