PC Hardware A Beginner’s Guide

(^498) PC Hardware: A Beginner’s Guide
FireWire Device Drivers
Virtually all of the later versions of popular operating systems, including Windows 98
and 2000, support IEEE 1394, but only if the device controller attached to the port sup-
ports the Open Host Controller Interface (OHCI) standard. Windows 2000 supports IEEE
1394 devices through its Serial Bus Protocol (SBP-2) drivers.

Wireless Ports

Wireless or cordless interfaces are becoming more popular for PCs. There are two types

ofwirelessconnectiontechnologiesinuseonPCs:infrared(IR)andradiofrequency(RF).

Infrared Ports

An infrared (IR) port uses an invisible band of light from the lower end of the electromag-

netic spectrum to carry data between a peripheral device and the PC. IR light is just out-

side of the light spectrum that humans can see. Infrared contrasts with ultraviolet (UV),

which is another invisible band of light, but at the other end of the spectrum. One use of

UV light, besides tanning your body, is that it will erase an EPROM after about ten min-

utes of exposure.

Using the invisible IR beam, IR devices, which are also called IrDA (Infrared Data As-

sociation) devices, can be connected to a PC without the use of a physical cable. IrDA is

the trade organization for the infrared device industry that has established a number of

standards defining and prescribing the use of the IrDA connection. IrDA ports, which are

the small oval-shaped dark red plastic windows built into cases, are common on note-

book and other portable computers.

IR devices are line-of-sight devices, which means that they must have a clear, unob-

structed path between their transmitters and receivers. IR devices are not new; IR is the

wireless mode most often used by TV remotes and other wireless controllers. If anything

Figure 19-13. A sample IEEE 1394 bus