文档介绍：How PCI Works
by Jeff Tyson
There are a lot of ponents in puter. And all of these parts need to
communicate with each other in a fast and efficient manner. Otherwise, the amazing speed and
capabilities of each ponent is lost in the whole.
A typical PCI card
That's where the es in. Essentially, a bus is the channel or path between the
components in puter. There are many different types of buses. In this edition of
HowStuffWorks, you will learn about some of those buses. We will concentrate on the bus
known as the ponent Interconnect (PCI). We'll talk about what PCI is, how it
operates and how it is used, as well as about past and future bus technologies.
Hop on the Bus, Gus
Buses have grown and evolved over the years in an effort to match the performance of all the
ponents. Even so, the evolution of the bus has been surprisingly slow
compared to other technologies. puters sold today still have an Industry Standard
Architecture (ISA) bus that will puter cards developed for the original IBM PC in the
early 1980s.
There have been a couple of key reasons for this bus longevity:
• There is a need for long-patibility with a large number of hardware
manufacturers.
• Before the rise of multimedia, few hardware peripherals fully utilized the speed of the bus.
A puter has two key buses. The first one, known as the system bus or local bus,