История компьютера и компьютерной техники
The Comparative Analisis Of The History Of The Computer Science And
The Computer Engineering In The USA And Ukraine.
HOWARD H. AIKEN AND THE COMPUTER
[pic]OWARD AIKEN’S CONTRIBUTIONS TO THE DEVELOPMENT OF THE COMPUTER
-NOTABLY THE HARVARD MARK I (IBM ASSC) MACHINE, AND ITS SUCCESSOR THE
MARK II - ARE OFTEN EXCLUDED FROM THE MAINSTREAM HISTORY OF COMPUTERS ON
TWO TECHNICALITIES. THE FIRST IS THAT MARK I AND MARK II WERE ELECTRO-
MECHANICAL RATHER THAN ELECTRONIC; THE SECOND ONE IS THAT AIKEN WAS NEVER
CONVINCED THAT COMPUTER PROGRAMS SHOULD BE TREATED AS DATA IN WHAT HAS COME
TO BE KNOWN AS THE VON NEUMANN CONCEPT, OR THE STORED PROGRAM.
It is not proposed to discuss here the origins and significance of the
stored program. Nor I wish to deal with the related problem of whether the
machines before the stored program were or were not “computers”. This
subject is complicated by the confusion in actual names given to machines.
For example, the ENIAC, which did not incorporate a stored program, was
officially named a computer: Electronic Numeral Integrator And Computer.
But the first stored-program machine to be put into regular operation was
Maurice Wiles’ EDSAC: Electronic Delay Storage Automatic Calculator. It
seems to be rather senseless to deny many truly significant innovations (by
H.H.Aiken and by Eckert and Mauchly), which played an important role in the
history of computers, on the arbitrary ground that they did not incorporate
the stored-program concept. Additionally, in the case of Aiken, it is
significant that there is a current computer technology that does not
incorporate the stored programs and that is designated as (at least by
TEXAS INSTRUMENTS() as “Harvard architecture”, though, it should more
properly be called “Aiken architecture”. In this technology the program is
fix and not subject to any alteration save by intent - as in some computers
used for telephone switching and in ROM.
OPERATION OF THE ENIAC.
Aiken was a visionary, a man ahead of his times. Grace Hopper and
others remember his prediction in the late 1940s, even before the vacuum
tube had been wholly replaced by the transistor, that the time would come
when a machine even more powerful than the giant machines of those days
could be fitted into a space as small as a shoe box.
Some weeks before his death Aiken had made another prediction. He
pointed out that hardware considerations alone did not give a true picture
of computer costs. As hardware has become cheaper, software has been apt to
get more expensive. And then he gave us his final prediction: “The time
will come”, he said, “when manufacturers will gave away hardware in order
to sell software”. Time alone will tell whether or not this was his final
look ahead into the future.
THE DEVELOPMENT OF COMPUTERS IN THE USA
[pic]N THE EARLY 1960S, WHEN COMPUTERS WERE HULKING MAINFRAMES THAT
TOOK UP ENTIRE ROOMS, ENGINEERS WERE ALREADY TOYING WITH THE THEN -
EXTRAVAGANT NOTION OF BUILDING A COMPUTER INTENDED FOR THE SOLE USE OF ONE
PERSON. BY THE EARLY 1970S, RESEARCHES AT XEROX’S POLO ALTO RESEARCH CENTER
(XEROX PARC) HAD REALIZED THAT THE PACE OF IMPROVEMENT IN THE TECHNOLOGY OF
SEMICONDUCTORS - THE CHIPS OF SILICON THAT ARE THE BUILDING BLOCKS OF
PRESENT-DAY ELECTRONICS - MEANT THAT SOONER OR LATER THE PC WOULD BE
EXTRAVAGANT NO LONGER. THEY FORESAW THAT COMPUTING POWER WOULD SOMEDAY BE
SO CHEAP THAT ENGINEERS WOULD BE ABLE TO AFFORD TO DEVOTE A GREAT DEAL OF
IT SIMPLY TO MAKING NON-TECHNICAL PEOPLE MORE COMFORTABLE WITH THESE NEW
INFORMATION - HANDLING TOOLS. IN THEIR LABS, THEY DEVELOPED OR REFINED MUCH
OF WHAT CONSTITUTES PCS TODAY, FROM “MOUSE” POINTING DEVICES TO SOFTWARE
Although the work at Xerox PARC was crucial, it was not the spark that
took PCs out of the hands of experts and into the popular imagination. That
happened inauspiciously in January 1975, when the magazine Popular
Electronics put a new kit for hobbyists, called the Altair, on its cover.
for the first time, anybody with $400 and a soldering iron could buy and
assemble his own computer. The Altair inspired Steve Wosniak and Steve Jobs
to build the first Apple computer, and a young college dropout named Bill
Gates to write software for it. Meanwhile. the person who deserves the
credit for inventing the Altair, an engineer named Ed Roberts, left the
industry he had spawned to go to medical school. Now he is a doctor in
small town in central Georgia.
To this day, researchers at Xerox and elsewhere pooh-pooh the Altair
as too primitive to have made use of the technology they felt was needed to
bring PCs to the masses. In a sense, they are right. The Altair
incorporated one of the first single-chip microprocessor - a semiconductor
chip, that contained all the basic circuits needed to do calculations -
called the Intel 8080. Although the 8080 was advanced for its time, it was
far too slow to support the mouse, windows, and elaborate software Xerox
had developed. Indeed, it wasn’t until 1984, when Apple Computer’s
Macintosh burst onto the scene, that PCs were powerful enough to fulfill
the original vision of researchers. “The kind of computing that people are
trying to do today is just what we made at PARC in the early 1970s,” says
Alan Kay, a former Xerox researcher who jumped to Apple in the early 1980s.
MACINTOSH PERFORMA 6200/6300
Researchers today are proceeding in the same spirit that motivated Kay
and his Xerox PARC colleagues in the 1970s: to make information more
accessible to ordinary people. But a look into today’s research labs
reveals very little that resembles what we think of now as a PC. For one
thing, researchers seem eager to abandon the keyboard and monitor that are
the PC’s trademarks. Instead they are trying to devise PCs with
interpretive powers that are more humanlike - PCs that can hear you and see
you, can tell when you’re in a bad mood and know to ask questions when they
don’t understand something.
It is impossible to predict the invention that, like the Altair,
crystallize new approaches in a way that captures people’s imagination.
Top 20 computer systems
[pic]ROM SOLDERING IRONS TO SPARCSTATIONS, FROM MITS TO MACINTOSH,
PERSONAL COMPUTERS HAVE EVOLVED FROM DO-IT-YOURSELF KITS FOR ELECTRONIC
HOBBYISTS INTO MACHINES THAT PRACTICALLY LEAP OUT OF THE BOX AND SET
THEMSELVES UP. WHAT ENABLED THEM TO GET FROM THERE TO HERE? INNOVATION AND
DETERMINATION. HERE ARE TOP 20 SYSTEMS THAT MADE THAT RAPID EVOLUTION
. MITS Altair 8800
There once was a time when you could buy a top-of-the-line computer
for $395. The only catch was that you had to build it yourself. Although
the Altair 8800 wasn’t actually the first personal computer (Scelbi
Computer Consulting`s 8008-based Scelbi-8H kit probably took that honor in
1973), it grabbed attention. MITS sold 2000 of them in 1975 - more than any
single computer before it.
Based on Intel`s 8-bit 8080 processor, the Altair 8800 kit included
256 bytes of memory (upgradable, of course) and a toggle-switch-and-LED
front panel. For amenities such as keyboard, video terminals, and storage
devices, you had to go to one of the companies that sprang up to support
the Altair with expansion cards. In 1975, MITS offered 4- and 8-KB Altair
versions of BASIC, the first product developed by Bill Gates` and Paul
Allen`s new company, Microsoft.
If the personal computer hobbyists movement was simmering, 1975 saw it
come to a boil with the introduction of the Altair 8800.
. Apple II
Those of you who think of the IBM PC as the quintessential business
computers may be in for a surprise: The Apple II (together with VisiCalc)
was what really made people to look at personal computers as business
tools, not just toys.
The Apple II debuted at the first West Coast Computer Fair in San
Francisco in 1977. With built-in keyboard, graphics display, eight readily
accessible expansion slots, and BASIC built-into ROM, the Apple II was
actually easy to use. Some of its innovations, like built-in high-
resolution color graphics and a high-level language with graphics commands,
are still extraordinary features in desk top machines.
With a 6502 CPU, 16 KB of RAM, a 16-KB ROM, a cassette interface that
never really worked well (most Apple It ended up with the floppy drive the
was announced in 1978), and color graphics, the Apple II sold for $1298.
. Commondore PET
Also introduced at the first West Coast Computer Fair, Commondore`s
PET (Personal Electronic Transactor) started a long line of expensive
personal computers that brought computers to the masses. (The VIC-20 that
followed was the first computer to sell 1 million units, and the Commondore
64 after that was the first to offer a whopping 64 KB of memory.)
The keyboard and small monochrome display both fit in the same one-
piece unit. Like the Apple II, the PET ran on MOS Technology’s 6502. Its
$795 price, key to the Pet’s popularity supplied only 4 KB of RAM but
included a built-in cassette tape drive for data storage and 8-KB version
of Microsoft BASIC in its 14-KB ROM.
. Radio Shack TRS-80
Remember the Trash 80? Sold at local Radio Shack stores in your choice
of color (Mercedes Silver), the TRS-80 was the first ready-to-go computer
to use Zilog`s Z80 processor.
The base unit was essentially a thick keyboard with 4 KB of RAM and 4
KB of ROM (which included BASIC). An optional expansion box that connected
by ribbon cable allowed for memory expansion. A Pink Pearl eraser was
standard equipment to keep those ribbon cable connections clean.
Much of the first software for this system was distributed on
audiocassettes played in from Radio Shack cassette recorders.
. Osborne 1 Portable
By the end of the 1970s, garage start-ups were pass. Fortunately there
were other entrepreneurial possibilities. Take Adam Osborne, for example.
He sold Osborne Books to McGraw-Hill and started Osborne Computer. Its
first product, the 24-pound Osborne 1 Portable, boasted a low price of
More important, Osborne established the practice of bundling software
- in spades. The Osborne 1 came with nearly $1500 worth of programs:
WordStar, SuperCalc, BASIC, and a slew of CP/M utilities.
Business was looking good until Osborne preannounced its next version
while sitting on a warehouse full of Osborne 1S. Oops. Reorganization under
Chapter 11 followed soon thereafter.
. Xerox Star
This is the system that launched a thousand innovations in 1981. The
work of some of the best people at Xerox PARC (Palo Alto Research Center)
went into it. Several of these - the mouse and a desktop GUI with icons -
showed up two years later in Apple`s Lisa and Macintosh computers. The Star
wasn’t what you would call a commercial success, however. The main problem
seemed to be how much it cost. It would be nice to believe that someone
shifted a decimal point somewhere: The pricing started at $50,000.
. IBM PC
Irony of ironies that someone at mainframe-centric IBM recognized the
business potential in personal computers. The result was in 1981 landmark
announcement of the IBM PC. Thanks to an open architecture, IBM’s clout,
and Lotus 1-2-3 (announced one year later), the PC and its progeny made
business micros legitimate and transformed the personal computer world.
The PC used Intel`s 16-bit 8088, and for $3000, it came with 64 KB of
RAM and a 51/4-inch floppy drive. The printer adapter and monochrome
monitor were extras, as was the color graphics adapter.
. Compaq Portable
Compaq’s Portable almost single-handedly created the PC clone market.
Although that was about all you could do with it single-handedly - it
weighed a ton. Columbia Data Products just preceded Compaq that year with
the first true IBM PC clone but didn’t survive. It was Compaq’s quickly
gained reputation for engineering and quality, and its essentially 100
percent IBM compatibility (reverse-engineering, of course), that
legitimized the clone market. But was it really designed on a napkin?
. Radio Shack TRS-80 Model 100
Years before PC-compatible subnotebook computers, Radio Shack came out
with a book-size portable with a combination of features, battery life,
weight, and price that is still unbeatable. (Of course, the Z80-based Model
100 didn’t have to run Windows.)
The $800 Model 100 had only an 8-row by 40-column reflective LCD
(large at the time) but supplied ROM-based applications (including text
editor, communications program, and BASIC interpreter), a built-in modem,
I/O ports, nonvolatile RAM, and a great keyboard. Wieghing under 4 pounds,
and with a battery life measured in weeks (on four AA batteries), the Model
100 quickly became the first popular laptop, especially among journalists.
With its battery-backed RAM, the Model 100 was always in standby mode,
ready to take notes, write a report, or go on-line. NEC`s PC 8201 was
essentially the same Kyocera-manufectured system.
. Apple Macintosh
Whether you saw it as a seductive invitation to personal computing or
a cop-out to wimps who were afraid of a command line, Apple`s Macintosh and
its GUI generated even more excitement than the IBM PC. Apple`s R&D people
were inspired by critical ideas from Xerox PARK (and practiced on Apple`s
Lisa) but added many of their own ideas to create a polished product that
changed the way people use computers.
The original Macintosh used Motorola’s 16-bit 68000 microprocessor. At
$2495, the system offered a built-in-high-resolution monochrome display,
the Mac OS, and a single-button mouse. With only 128 KB of RAM, the Mac was
underpowered at first. But Apple included some key applications that made
the Macintosh immediately useful. (It was MacPaint that finally showed
people what a mouse is good for.)
. IBM AT
George Orwell didn’t foresee the AT in 1984. Maybe it was because Big
Blue, not Big Brother, was playing its cards close to its chest. The IBM AT
set new standards for performance and storage capacity. Intel`s blazingly
fast 286 CPU running at 6 MHz and 16-bit bus structure gave the AT several
times the performance of previous IBM systems. Hard drive capacity doubled
from 10 MB to 20 MB (41 MB if you installed two drives - just donut ask how
they did the math), and the cost per megabyte dropped dramatically.
New 16-bit expansion slots meant new (and faster) expansion cards but
maintained downward compatibility with old 8-bit cards. These hardware
changes and new high-density 1.2-MB floppy drives meant a new version of PC-
DOS (the dreaded 3.0).
The price for an AT with 512 KB of RAM, a serial/parallel adapter, a
high-density floppy drive, and a 20-MB hard drive was well over $5000 - but
much less than what the pundits expected.
. Commondore Amiga 1000
The Amiga introduced the world to multimedia. Although it cost only
$1200, the 68000-based Amiga 1000 did graphics, sound, and video well
enough that many broadcast professionals adopted it for special effects.
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