1–6
Introduction to the AlphaPC 164UX Motherboard
System Components and Features
1.1.4 PCI Interface Overview
The AlphaPC 164UX PCI interface is the main I/O bus for the majority of functions
(SCSI interface, graphics accelerator, and so on). The PCI interface has a 33-MHz
data transfer rate. An onboard PCI-to-ISA bridge is provided through an Intel
82371SB (SIO) chip.An onboard PCI-to-PCI bridge is provided through an DEC
21052 chip.The AlphaPC 164UX includes advanced features,Such as :six PCI
slots;on-board Ultra-Wide SCSI; on-board 10/100 Mbs Ethernet.
1.1.5 ISA Interface Overview
The ISA bus provides the following system support functions:
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One expansion slots.
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An SMC FDC37C666 combination controller chip that provides:
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A diskette controller.
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Two universal asynchronous receiver-transmitters (UARTs) with full
modem control.
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A bidirectional parallel port.
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A mouse and keyboard controller.
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Real Time Clock.
1.1.6 Miscellaneous Logic
The AlphaPC 164UX contains the following miscellaneous components:
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Synthesizer for clocks:
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A clock synthesizer (TQ2061) provides a programmable clock source from
300MHz to 800MHz to the 21164 microprocessor. The microprocessor
supplies a clock to the system PLL/clock buffer for the 21174.
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The 21174 core logic chip provides the SDRAM and PCI clocks.
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24MHz clock generator provide a clock source for the FDC37C666 ISA
device controller. The controller’s onchip generator then provides other
clocks as needed.
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AMD PALLV22V1015 and PALCE16V8H programmable logic devices (PLDs)
for PCI bus arbitration.
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Altera EPM7032-7 for DMA boundary issue.
