Specifications

17 January 1997 – Subject to Change
Introduction to the AlphaPC 164 Motherboard 1–5
System Components and Features
1.1.5 ISA Interface Overview
The ISA bus provides the following system support functions:
•
Two expansion slots.
•
An SMC FDC37C935 combination controller chip provides:
– A mouse and keyboard controller
– A diskette controller
– Two universal asynchronous receiver-transmitters (UARTs) with full
modem control
– A bidirectional parallel port
– A time-of-year (TOY) clock
•
Operating system support—provided by a 1MB flash ROM that contains
supporting firmware.
1.1.6 Miscellaneous Logic
The AlphaPC 164 contains the following miscellaneous components:
•
Clocks
– A 36.66-MHz oscillator (default) and X10 phase-locked loop (PLL) clock
generator provide a clock source to the 366 MHz 21164 microprocessor. The
microprocessor supplies a clock to the system PLL/clock buffer for the
chipset and PCI devices.
– A 14.318-MHz crystal and frequency generator provide a clock source for
the FDC37C935 ISA device controller. The controller’s onchip generator
then provides other clocks as needed.
– A 32-kHz crystal provides the TOY clock source.
•
Serial ROM – A Xilinx XC17128 serial ROM (SROM) contains initial code that
is loaded into the 21164 instruction cache (Icache) on power-up. A serial line
interface is also provided to allow direct connection to a terminal line for
debugging purposes.
•
AMD MACH210-15 programmable logic devices (PLDs) for interrupts and PCI
bus arbitration.