American Megatrends Excalibur PCI, User Manual

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Chapter 2 PCI
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Chapter 2
PCI Local Bus
PCI is a specification for a local bus standard. The PCI specification also provides the electrical specifications for
peripheral chip makers and the logic requirements for a PCI Controller. While PCI defines a local bus standard, it also
defines a standard component-level interface. PCI is a common I/O component interface.
The Excalibur PCI Motherboard conforms to the Intel PCI specifications. The PCI Local Bus Specification is a
standard set of interface, architecture, timings, electrical, and physical specifications that permits all PCI Local Bus
products to be totally interchangeable. PCI is a multiplexed extension of the CPU bus. In PCI, the CPU bus control
mechanisms have been extended to optimize I/O support. PCI establishes a local bus standard in which a large variety of
I/O components can be directly connected without using any glue logic.
What PCI Accomplishes
PCI is a way to physically interconnect highly integrated peripheral components and processor/memory systems.
PCI Features
Up to ten PCI loads can be used in the same system on the PCI bus, including the PCI Controller and an expansion
bus controller for EISA, ISA, or MCA. PCI decouples the CPU from the expansion bus and works at 33 MHz but can use
either a 32-bit or 64-bit data connection path to the CPU.