Octek DRAGON EISA 486, Manual

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GENERAL FEATURES
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EISA BUS
Since the inception eleven years ago, the growth
of the business personal computer market has been
driven to a substantial degree by the emergence of a de
facto industry standard. This industry standard grew
from the original IBM PC system architecture and
evolved tremendously in the ensuing years. There are
three key elements of this architecture: Intel 8086-family
of microprocessors, an "open" I/O bus and the MS-DOS
operating system.
The benefit of the industry-standard architecture
(ISA) to the PC users have been enormous. ISA has
provided a stable platform for software and hardware
development which has given customers the largest
selection of products in the history of computing. ISA
has also facilitated the rapid utilization of the latest
technology in PCs in a compatible manner, protecting the
customers' investment. It has also freed customers from
a single-vendor, proprietary architecture and for the first
time, given customers real freedom of choice in selecting
the best computers, software and peripherals to meet
their needs. Over the last eleven years, ISA has become
a customer-controlled standard rather that a vendor-
controlled standard.
In this eleven year, each key elements of this
industry-standard architecture has evolved significantly.
In 1984, IBM introduced Intel's 80286 processor to
personal computers and extended the existing 8-bit open
I/O bus to 16-bit capabilities in a compatible manner. In
1986, fully compatible personal computers were
introduced to the market using Intel's next generation
microprocessor, the 386. At the processor subsystem
level, the full 386 capabilities were harnessed, but
without a compatible 32-bit extension to the ISA I/O bus.
The 386 was introduced in this manner because of the
enormous customer demand for higher processor
performance. At the time, the 32-bit I/O bus extension
was not needed since most of the I/O peripherals did not