Synergy User Manual and Tutorial. - THE CORE MEMORY

Synergy User Manual and Tutorial
interrupt controller, two direct memory access (DMA) channels (with
controller), and timing circuitry (three timers). It replaced 22 separate
VLSI and transistor-transistor logic (TTL) chips and was more cost
efficient than the chips it replaced. In 1982, Intel developed the 80286
processor, which had 134,000 transistors, a 1.5-micron die, and could
address up to 16 megabytes of memory. This microprocessor was the
first to introduce the protected mode, which allowed the computer to
multitask by running more than one program at a time by time-sharing
the systems resources. Its initial models ran at 8, 10 and 12.5 MHz but
later models ran as fast as 20 MHz. The 80386 processor was released in
1985 with 275,000 transistors, a 1.0-micron die, a 32-bit instruction and
a 32-bit memory address space that could address up to four gigabytes of
RAM. It had the ability to address up to 64 terabytes of virtual memory. The initial
clock speeds were 16, 20, 25, and 33 MHz. It also had a feature called instruction
pipelining, which allowed the processor to run the next instruction before finishing the
previous instruction. It had a virtual real time mode that allowed more than one running
session of real time programs, a feature that is used in multitasking operating systems.
This chip also had a system management mode (SMM), which could power down various
hardware devices to decrease power use. In 1989, Intel introduced the 80486 line of
processors with 1.2 million transistors, a 1.0-micron die, and the same instruction and
memory address size as the 386. This was the first microprocessor to have an integrated
floating-point unit (FPU). Previously, CPUs had to have an external FPU, called a math
coprocessor, to speed up floating-point operations. It also had 8 kilobytes of on-die
cache, which stored predicted next instructions for pipelining. This saved an access to
main memory, which is much slower than cache memory. Later 486 models could
operate at greater speeds that the maximum system bus speed. The 486DX2/66 was a
clock doubled 33 MHz to 66 MHz and the 486DX4/100 was clock a tripled 33 MHz to
100 MHz.
In 1993, Intel released the Pentium processor with 3.21 million
transistors and a 0.8-micron die. Clock speeds were available
from 60 to 200 MHz, with a 60 MHz processor capable of 100
MIPS. It had the same 32-bit address space as the 386 and 486
but had an external data bus width of 64 bits and a superscalar
architecture (able to process two instructions per clock cycle),
which allowed it to process instructions and data about twice as
fast as the 486. Internally, this chip was actually two 32-bit
processors chained together that shared the workload. It had
two separate 8 KB caches (one data and one instruction cache) and a pipelined FPU,
which could perform floating-point operations much faster than the 486. Later versions
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