DECchip 21171 Core Logic Chipset

This document provides a comprehensive technical reference for the DECchip 21171 core logic chipset, which is designed to support the Alpha 21164 microprocessor in high-performance uniprocessor systems.

The manual is organized into two parts:

• Part I: DECchip 21171-CA (CIA) Information: Covers the Control, I/O interface, and Address (CIA) chip, including pin descriptions, detailed architecture, control and status registers (CSRs), power-up/initialization, and system address mapping.
• Part II: DECchip 21171-BA (DSW) Information: Details the Data Switch (DSW) chip, providing pin descriptions and an architectural overview.

The chipset facilitates a 64-bit PCI bus interface, 256-bit ECC-protected memory paths, and support for up to 8GB of physical memory. It includes detailed register maps, timing specifications, and configuration details for memory and PCI address windows.