User`s manual

1
Introduction to the EB164
This chapter provides an overview of the EB164 motherboard and describes
the EB164, its components, features, and uses.
1.1 System Components and Features
The EB164 is implemented in industry-standard parts and uses a Digital
Semiconductor 21164 Alpha microprocessor (21164) running at 266, 300, or 333
MHz. The functional components are shown in Figure 1–1 and are introduced
in the following subsections.
1.1.1 Digital Semiconductor 21171 Core Logic Chipset
The 21164 is supported by the Digital Semiconductor 21171 (21171) chipset.
The 21171 consists of the following two application-specific integrated circuit
(ASIC) types:
• One copy of the 21171-CA control, I/O interface, and address chip (CIA)
provides the interface between the 21164, main memory (addressing and
control), and the peripheral component interconnect (PCI) bus. It also
provides the data switch companion chips with control information to direct
the data flow.
• Four copies of the 21171-BA data switch chip (DSW) provide the memory
interface data path and route PCI data through the CIA chip.
The chipset includes the majority of functions required to develop a high-
performance PC or workstation, requiring minimum discrete logic on the
module. It provides flexible and generic functions to allow its use in a wide
range of systems.
Introduction to the EB164 1–1