AlphaPC64 Evaluation Board User's Guide

This User's Guide provides a comprehensive description of the AlphaPC64 Evaluation Board, an evaluation and development module for computing systems based on the Alpha 21064A microprocessor.

Key aspects covered in the document include:

1. Introduction and Overview:

   • The AlphaPC64 serves as a single-board hardware and software development platform for designing, integrating, and analyzing systems built around the Alpha 21064A CPU (running from 150 MHz to 275 MHz).
   • It also supports the development of Peripheral Component Interconnect (PCI) I/O devices.

2. System Components & Features:

   • Memory Subsystem: Supports 16MB to 512MB of DRAM (128-bit data bus) and a configurable Level 2 (L2) cache ranging from 512KB to 8MB (128-bit data bus).
   • DECchip 21072 Support Chipset: Consists of three chips:
     • 21071-CA: Manages CPU, cache, and main memory interfaces, including the cache and memory controller.
     • 21071-BA: Provides a 32-bit data path from CPU to memory and I/O (four chips create the 128-bit interface).
     • 21071-DA: Acts as a bridge between the CPU and the PCI bus.
   • PAL Control Set: A 4-PAL set handles L2 cache functions, interrupt address decoding, and PCI/ISA interrupts.
   • Clock Subsystem: Provides clocks to the chipset and PCI devices, with configurable CPU clock divisors (2-17) and support for 250 MHz to 700 MHz output frequencies.
   • PCI Interface: Offers selectable speeds (25 MHz or 33 MHz) and features an Intel 82378ZB Saturn IO (SIO) chip as a PCI-to-ISA bridge, with three dedicated and one shared expansion slot.
   • ISA Interface: Includes expansion slots and system support functions via chips like the Intel 8242 (keyboard/mouse), National 87312 (diskette, serial/parallel ports, IDE controller), and Dallas DS1287 (Time-of-Year clock). A 1MB Flash ROM is also part of the ISA interface.

3. Software Support:

   • Includes a 1MB Flash ROM with debug monitor code, offering capabilities like file downloading, memory/register examination, disassembly, and debugging.
   • A Serial ROM (SROM) contains the 21064A initialization code, which then loads and transfers control to the Flash ROM.
   • The board is designed to run operating systems like Windows NT, Digital UNIX, and OpenVMS.
   • Full design database, schematics, and source files are provided for design support.

4. Configuration and Addressing:

   • Details the use of jumpers for configuring clock frequency and L2 cache size/speed.
   • Describes the mapping of the 34-bit processor address space to memory and I/O, including translations to PCI addresses (Sparse I/O, Configuration, Sparse Memory, Dense Memory, Interrupt Acknowledge/Special Cycle).

5. Board Requirements:

   • Outlines power requirements (standard PC power supply, ~96.2 W dissipation excluding peripherals), environmental characteristics (operating and storage temperatures), and physical board parameters (baby-AT size: 22.1 cm x 33.0 cm).

The document is intended for system designers and others evaluating or designing computer systems based on the Alpha 21064A microprocessor, providing detailed functional descriptions, register information, and ordering details for related products and literature.