Octek HAWK 486, Manual

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GENERAL
FEATURES
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2-3
PROCESSOR
The power of HAWK comes from 80486. 80486 is the
state-of-art microprocessor which merges many innovative features on a
single chip for advanced applications and operation systems. Fabricating
with the 1um process, this CPU consists of more than one million
transistors. With such high density, this CPU incorporates as many as
new features to make itself the most powerful microprocessor.
80486 is a 32-bit microprocessor with 32-bit external data bus
and 32-bit external address bus. It not only contain a central processing
unit, but also integrates a numeric processor and a four-way set associate
cache memory. It is fully binary compatible with 80386 and 80387. All
existing software for PC XT/AT can be used on OCTEK HAWK-486.
However, due to the new internal architecture, the performance of 80486
is two to four times of 80386.
Cache memory can improve the overall performance of a
computer system. Nevertheless, if the cache memory is separated from
CPU, CPU still needs to fetch code and data through external bus. That
means the data transfer rate should not be too fast so that the external
devices are able to keep pace with the CPU. In 80486, the cache
controller and cache memory are integrated into the chip. Most of the
operations can be carried out inside the CPU, which reduces the bus
operations on external data and address bus and thus speeds up the
internal execution.