information, once recorded, cannot be erased or
changed, but it can be read many times. The expression
Write Once, Read Many (WORM) describes this type of
technology.
SWITCH BOXES.— When you want to share
printers, you can connect them through a switch or
switch box. For example, two or more computers can
use one printer, or one computer can use two or more
printers. As you can see, you will need a cable between
the switch box and each device. You then switch the
setting, A or B, on the box to switch signal lines without
disconnecting and reconnecting cables. Switches range
from this simple, manually operated switch box with
two settings to switches that select signal lines
automatically and provide buffering capability. Some
also provide for both parallel and serial devices.
MODEMS.— Modems provide communication
between systems. Through them, your system can send
or receive data over phone lines. You may also use a
null modem cable for communication between systems
that are close enough to each other to be connected by
cable. A null modem cable creates a communications
link that allows devices to communicate without using
modems and phone lines. To make the systems and null
modem cable fit together, you may need a gender
connector or gender changer to bridge two like
connectors.
As you can see, a basic (low-end) system is only a
beginning.
As you become more familiar with
microcomputers and as technology changes, you will
find more and more capabilities and more uses for
microcomputers.
SETTING UP AND OPERATING
MICROCOMPUTERS
Before you begin to set up or operate a
microcomputer, know what you are going to do.
THINK FIRST. Start with the documentation, NOT
with the hardware and software.
USING DOCUMENTATION
The first thing you will want to do when you install
or start using a system or a new software package is
become familiar with the documentation that comes
with it. You will also want to see what other
documentation and training materials are available.
Don’t get discouraged over the amount of reading
material provided to you. It takes time to learn
something new, and it takes practice to become
proficient. Spend time learning all you can about the
software and hardware. Refer to manuals and other help
aides when you have problems. You may also have in-
house user manuals to use.
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