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История компьютера и компьютерной техники

История компьютера и компьютерной техники

ESSAY

The Comparative Analisis Of The History Of The Computer Science And

The Computer Engineering In The USA And Ukraine.

.

USA.

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.

9

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

“WINDOWS”.

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

POSSIBLE.

. 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

$1795.

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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