(^464) PC Hardware: A Beginner’s Guide
Radio frequency (RF) connection The most common form of cordless
devices uses digital radio technology to connect a keyboard (or mouse) to the
PC. The advantages of RF cordless devices include that they do not require a
line of sight to work and have a range of up to six feet from the receiver. The
keyboard actually communicates to the PC through a transceiver unit that
attaches to the PC through either a PS/2 or USB port. The transceiver usually
has a five- to six-foot cord with it so that it can connect to the port in the rear
of the PC and still sit in front of the PC.
The Mouse
What is probably the most amazing thing about a PC mouse such as the one shown in
Figure 18-19 is that it took so long to become a standard part of the PC’s equipment. It is
perfectly natural for a user to point at objects on the display instead of typing in a com-
mand, and many attempts were made to develop such a tool for the PC. Light pens,
touch screens, graphics tablets, and joysticks, among other devices, were all tried, but
none satisfied the user as a workable, intuitive pointing device.
The mouse was introduced with the Apple Macintosh and was an immediate success.
The mouse was the natural, intuitive, inexpensive pointing device users wanted. But, it
wasn’t until the early 1980s, when Windows and its graphical user interface (GUI) was
released, that the PC had an operating system that could work with the mouse. Since that
time, the mouse has become a standard equipment on virtually all PCs.
There are three types of mouse units used with PCs: Mechanical mouse This is the older style of mouse used with early
Macintosh and PC GUI systems. In a mechanical mouse, the movement of
a rubber ball causes a pair of wheels to spin that sensors detect to send data
signals to the PC.Figure 18-18. A USB connector and port