Digital Semiconductor AlphaPC 164 Motherboard Technical Reference Manual

This technical reference manual provides comprehensive details for system designers and evaluators of the Digital Semiconductor AlphaPC 164 Motherboard. This motherboard serves as a hardware and software development platform, featuring the Digital Semiconductor 21164 Alpha microprocessor (supporting up to 500 MHz) and the 21172 core logic chipset (CIA and DSW components).

Key specifications include a flexible memory subsystem supporting up to 512MB DRAM via SIMMs (128-bit or 256-bit bus) and a 1MB L3 Bcache. For I/O, it offers a 33 MHz PCI bus with four expansion slots (two 64-bit, two 32-bit) and an ISA bus with two expansion slots, along with an onboard combination controller for peripherals like keyboard, mouse, diskette, serial, and parallel ports.

The AlphaPC 164 utilizes a 1MB Flash ROM for primary firmware (Windows NT ARC or Alpha SRM Console) and a 64KB fail-safe booter for system recovery. Configuration is managed via jumpers for aspects like CPU speed, memory bus width, and boot options. The manual also details power and environmental requirements, address mapping schemes (dense, sparse, direct, scatter-gather), interrupt handling, system clocks, and procedures for upgrading memory and the microprocessor. Supporting software, design files, and additional documentation resources are also outlined.