CHAPTER 2
PERSONAL COMPUTER VIDEO
DISPLAYS AND INPUT DEVICES
INTRODUCTION
The video display is one of the versatile pieces of equipment in a computer
system. When used in a large system, it displays the status of computer operations
and displays the results of maintenance programs. When used with a personal
computer, the video monitor is the primary output device the computer uses to
communicate with the user.
In addition to having a video monitor as an output device, most computers also
have at least one input device, such as a keyboard. The input devices enables the
user to control the computer.
After completing this chapter, you should be able to:
Describe the operation of video display monitors used with personal
computer systems
Describe the operation of MDA, CGA, EGA, VGA, SVGA, and XGA
graphics adapters used to drive video monitors
Describe the operation of flat screen displays using liquid crystal
display technology
Describe the operation of various input devices used with video display
terminals
VIDEO DISPLAY MONITORS
AND ADAPTERS
The video display monitor is the primary output
device that interfaces the user to the computer. In
this section, we cover the different types of video
displays used with personal computers.
Video displays have two main components: the
video monitor and a video adapter.
The video
adapter is plugged into the PC’s motherboard.
VIDEO DISPLAY MONITORS
Video display monitors come in a variety of
shapes, sizes, and capabilities. They can be color or
monochrome, use interlaced or noninterlaced scan,
and require either analog or digital (cathode-ray tube
[CRT]) drive signals.
Composite video monitors are the simplest type
of monitor. The video signal is combined on a
single line with the horizontal and vertical timing
signals before being sent to the monitor. The
monitor electronics separate the video signals and the
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