are correct for a job, selecting a utility program to copy a
file or create a new file by specifying the parameters,
and working with an online database management
system that keeps up-to-date information on inventory
management or personnel.
In looking over these last few paragraphs, possibly
you see yourself as a worker, a supervisor, a teacher, and
a troubleshooter, and rightly so. Microcomputers make
up a significant part of your profession; and because of
this, you will be the person that others will come to
looking for answers to their questions. The mere fact
that you are a communications specialist gives the
outside world, the end users, the impression you know it
all; that is, all there is to know about mainframes, minis,
and particularly microcomputers.
WORKING WITH HARDWARE
Microcomputers come in many shapes and sizes
with a variety of capabilities. A microcomputer can be
designed to operate in a stand-alone configuration or as
a component, an intelligent terminal, a server for a
complex local-area network (LAN) or large
distributed system. In this chapter, we will focus our
attention on desktop microcomputers that operate in a
stand-alone environment. Most stand-alone, desktop
microcomputer systems contain at least five hardware
components. They are as follows:
. The computer or system unit, which normally
houses the microcomputer (microprocessor
chip[s]) along with other hardware components
and secondary storage devices;
. Secondary storage devices (floppy disk drives,
hard disk drives, and magnetic tape units),
housed either in the system unit or separately;
. A monitor (standard output device);
. A keyboard (standard input device); and
. A printer (an additional output device—for hard
copy).
THE MICROCOMPUTER
In this section, we will examine the microcomputer
with its individual hardware components. We will
examine it from the inside. You will see how the
components work and how they interface and
interconnect with one another.
There will come a time when you maybe required
to replace or add a board in a computer to upgrade or
expand the capabilities of the system. A few examples
are as follows:
You may need to install an expanded memory
board to increase the amount of RAM to
accommodate larger applications.
You may have to replace the enhanced graphics
adapter (EGA) board with an video graphics
array (VGA) board to upgrade the graphics
capabilities of your system.
You may need to install a communications
board.
You may receive a new software release that
requires the presence (or absence) of certain boards to
function properly. You do not want to find out too late
that your software is incompatible with your hardware.
You might have to answer questions such as the follow-
ing: Will the graphics software the user wants to order
work with the graphics board currently installed in the
system? Does the user’s system have sufficient room to
accommodate another hard disk drive? A diagnostics
routine may indicate that the disk controller board needs
to be replaced, and so on, and so on. For reasons such as
these, you will need to know a lot more about microc-
computers (both inside and out) if you are to be effective
and able to help others in your work environment.
The Computer or System Unit
The computer or system unit is the main part or
heart of the total microcomputer system. Inside this unit
all data is processed, arithmetic and logic functions are
performed, and control is maintained for the system. If
you were to remove the outer cover from this unit
(figure 1-8), you would see a power supply and as many
Figure 1-8.—A microcomputer system unit with the cover
removed.
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