|
Early Computers |
|
|
Early Computers |
|
| UNIVAC COBAL MCS-4 Microcomputer The MITS Altair 8800 VAX Computer |
Babbage's Calculating Engines 1832-71
Charles
Babbage's calculating engines are among the most celebrated icons in
the
prehistory of computing. His Difference Engine No. 1 was the first
successful
automatic calculator and remains one of the finest examples of
precision
engineering of the time.
The portion shown was assembled in 1832 by Babbage's engineer, Joseph
Clement.
It consists of about 2000 parts and represents one-seventh of the
complete
engine. This 'finished portion of the unfinished engine' was
demonstrated
to some acclaim by Babbage, and functions impeccably to this day. The
engine
was never completed and most of the 12 000 parts manufactured were
later
melted for scrap.
Left: Portion of Difference Engine No. 1 assembled in 1832.
Right: Carriage mechanism of Charles Babbage's Difference Engine No. 2, completed by the Science Museum in 1991
Article on the History of the Babbage Difference Engine
From Charles Babbage's idea's, the First electronical computers were concieved 70 years later. Harvard University was the first to take this task on, and they began work on the Mark I under the direction of Howard Aiken in 1941. Through the use of banks of electromechanical relays that served as on and off switches. It handled 23 decimal places, and four arithmetic operations. Moreover it had special programs to handle logarithms and trigonometric functions. Mathmeticians were amazed at the power of the Mark I, as it could, in one day, complete the task it would take a man six months. However, the Mark I was soon to be outpaced by the new Electronic Numerical Integrator and Computer (ENIAC)
Financial backing from the US Census Bureau, gave Mauchly and Eckert the money to build their second digital computer the BINAC, which helped calculate the 1950 census. Moreover it gave them enough money to start their work on the UNIVAC.
Because ofthe difficult operation ofthe ENIACC, Matmetician John von Neumann began work on a theoretical study of computation that demonstrated that a computer could have a very simple, fixed physical structure and yet be able to execute any kind of computation effectivly by means of proper programmed control without the need for any changesin hardware. By doing this, Von Neumann contributed a new understanding ofhow practical fast computers should be organized, and built; these ideas, often fererred to as the stored-program technique, became fundamental for the future generations of high-speed computers.
From Wikipedia, the free encyclopedia.
Colossus was an early special purpose electronical computer built by the British government in order to break a German encryption method during the second world war.
Colossus was used to break the Geheimfernschreiber? (also known as fish or Lorenz) encryption method, a successor to Enigma used for highest-level German communications.
The project to construct Colossus was headed by the mathematician Max Newman. It started early in 1943 and the first version of the machine (Mark 1 Colossus) started working in January 1944, to be followed by the improved Mark 2 Colossus in June 1944. Ten Mark 2 Collossus machines were in use at Bletchley Park by the end of the war.
The machine used vacuum tubes and read a cypher text from a paper tape and then applied a programmable logical function to every character, counting how often this function returned "true".
It was a highly secret device and had therefore not much influence on the development of later computers. Nearly all documentation and machinery was classified immediately after the war, and destroyed in 1960s. Information about Colossus reemerged in the 1970s.
Colossus has been partly rebuilt by Tony Sale and is on display in the Bletchley Park Museum in Milton Keynes, Buckinghamshire.
Because of financial problems, Mauchly and Eckert, sold out to Remington Rand, and with Rand's substantial finacncial resources, they completed their first project. The UNIVAC (Universal Automatic Computer) which was a result of Neumann's "stored memory" made the computer "automatic," which meant it didnt require constant monitoring by engineers, and it was this computer that was delivered to the Census Bureau in March of 1951.
The development of the "stored memory" in the UNIVAC prompted Grace Hopper, a naval engineer, to begin work on a program which would convert english to binary, the computer language. This would be the base of all other programs, in order that people would no longer have to write in "machine language" This would speed up the programming by enormouse amounts, and begin the use of computers as multipurpose "engines."
The Intel 4004. It was supposed to be the brains of a calculator. Inste ad, it turned into a general-purpose microprocessor as powerful as ENIAC.
The MCS-4 computer used:
|
 |
First year of production : 1975
Approx. Value : $1200
Manufacturer : MITS (Micro Instrumentation and Telemetry
Systems)
Number Produced: Unknown
Description :
Considered by many to be the first microcomputer, the MITS altair 8800 was based on a 2 MHz Intel 8080 with 256 bytes standard RAM and interfaced with the user through the octal front panel switches. The unit shown here has an 8" floppy disk drive.
From InfoCulture: The Smithsonian Book of Information Age Inventions:
It was the Altair 8800, on the January 1975 cover of Popular Electronics, that really set off the (personal computer) boom. A company called MITS, in Albuquerque, sold the Altair for $395 as a kit and $495 assembled. Within three months 4,000 people had ordered it.
From Landmarks In Digital Computing: A Smithsonian Pictorial History:
Hobbyists who successfully put together their Altairs ended up with a
blue,
box-shaped machine that measured 17x18x7 inches. To enter programs or
data,
one set the toggle switches on the front. There was no keyboard, video
terminal or paper tape reader. All programming was in the machine code
of binary digits. The first Altairs came with only 256 bytes of memory;
they also lacked output devices such as printers. Results of a program
were indicated by the pattern of flashing lights on the front panel.
Interview with Ed Roberts - Designer of the Altair 8800
Front Panel of the Altair 8800
Description :
Shown above are an Apple I and a MITS Altair 8800. The Apple I was
produced in 1976, and about 200 were built. It used a 6502 processor
and
came with 4K of RAM. The estimated current market value of an Apple I
exceeds
$40,000!
The MITS Altair 8800 was considered the first microcomputer. It went
into
production in 1975, and was based on the Intel 8080. It is valued at
$1200.
Ah yes, the venerable old VAX line of computers sure brings back memories, very pleasant memories. I started my career on the even older PDP-11 line, but moved to the VAX when it began superceding those old systems. Even today, I have yet to find an operating system and hardware combination that was so perfect as the VAX. Here is a short history, just for old times sake.
In early 1975 a team was put together to create a new machine intended to replace the older PDP-11 series of computers. The PDP-11 line was doing great and was the mainstay of Digital Equipment Corporation's line of equipment, but it was time to create something new and more powerful.
The VAX was released on October 25, 1977 at the Digital Equipment Corporation's Annual Meeting of Shareholders. It was the first commercially available 32 bit machine and was a major milestone in computer history.
The VAX and it's operating system VMS (later renamed OpenVMS) were
revolutionary
in many ways. In addition to it's 32-bit architecture, this was the
first
machine/operating system combination that was designed from the ground
up. This produced an incredibly well-meshed system that worked
extraordinarily
well and lasted for a long time. In fact, the VAX machine was designed
to last from ten to fifteen years.
|
|
|
This is a VAX-11/780. It could perform at one million instructions per second (huge at the time). |
The first VAX-11/780 got installed at Carnegie Mellon University. In 1978 it was installed at CERN in Switzerland and the Max Planck Institute in Germany.
 |
|
The VAX-11/750 was smaller than the VAX-11/780, but still powerful. |
Within a few years, Digital released the VAX-11/750 systems, which were designed to replace the high-end PDP-11 computers. Since Digital also provided an upgrade path via compatibility mode, many customers switched to the newer hardware.
One of the great things about the VAX line was the VMS operating system. Excluding Windows 2000, VMS is still far superior in many ways to modern operating systems on PCs. In fact, the clustering capability that was added to VMS is still years in advance of anything in Windows NT or any other operating system for that matter.
In 1980 Version 2 of VMS was released. In this year VMS reached 1,400 sites, which was quite a large number of sites at the time.
 |
|
Here is the VAX-11/730 machine, smaller than the VAX-11/780 but still powerful. |
In 1982 Digital released the VAX-11/730, which was even smaller than the VAX-11/750. This was the third member of the VAX line, and it was really just a scaled down version of the previous two machines. But it was a lot cheaper and appealed to a larger base of customers.
By 1982 Digital Equipment Corporation was the number two computer company. IBM maintained it's lead as number one.
A large number of users who attended the 1982 and 1983 DECUS (Digital Equipment Corporation Users Society) events came away feeling lost and angry due to the announcements that the respected PDP-11 line was being discontinued in favor of the VAX. I remember these days as very angry times for many of us in the field. We had grown to love RSTS/E (the PDP-11's flagship operating system) and felt betrayed by the decisions to cancel it. Due to the overwhelming emotion Digital "reversed" itself, saying it was not canceling the line after all. But we all knew it was just a matter of time.
That actually turned out to be fine, as VMS was becoming a mature, well designed operating system. It borrowed many good concepts from RSTS/E and RSX (the two primary PDP-11 operating system) and built upon them to produce an even better system. This is much the same way that Windows NT borrowed many of it's design concepts from VMS (as it turns out, Windows NT was designed by many of the people who created the VAX line). Many of us in those days felt that RSTS/E was a better operating system, but the truth is that VMS matured into a beautiful product.
 |
|
This is a picture of the VAX-11/785 system. |
After the VAX-11/730 came out, customers demanded a more powerful VAX. Digital responded with the VAX-11/782, which was two VAX-11/780 processors sharing the same memory. This was followed by the VAX-11/785 system, which ran much faster.
In October 1984 Digital announced the VAX 8600, which was the first of a second generation of VAX machines. By 1986 Digital had announced the 8800, 8300 and 8200 systems. A year later it announced the 8974 and the 8978.
 |
|
Pictured here is the revolutionary MicroVAX II machine. |
The MicroVAX was launched in July of 1982 and it was shipped in May 1985. The MicroVAX II was very different than the earlier VAXes. It was cheaper (the first VAX for under $20,000) and it was fast. In fact, it's processor speed was as fast as the VAX-11/780.
I've spent many years working away on the MicroVAX II machines. They were reliable, sturdy and extremely well designed. At the time, in the mid- to late 1980's, this was the machine to get, as it could support almost anything needed by a business without the larger cooling and electrical requirements of the larger VAX systems.
The systems became even smaller when Digital released the Vaxstation 2000, which cost less than $5,000 per machine! At the time this was an incredibly low price for the hardware and software that was provided.
in 1992 Digital released the Alpha, which was a 64-bit RISC (reduced instruction set) machine which ran a modified version of VMS called AXP. This machine was fast - in fact, it broke many of the speed and performance records in place at the time.
In the mid-1990's, VMS was renamed OpenVMS and supported standards such as OSF/Motif, POSIX, XPG4 and DCE.
Digital Equipment Corporation was sold to Compaq in 1998. The VAX line is now thoroughly dead. The Alpha running OpenVMS is still sold and from what I understand it is doing very well. Many customers still run VAX hardware, but it is only a matter of time until those machines are no longer supported or maintainable. Of course, Compaq will continue to provide support for several more years, but the writing is on the wall. The VAX is dead, Long live the VAX! .(The alpha is still alive and doing well, though).
Sigh. well, those where the days. I could go on and on about how great and wonderful this technology was, and about how much fun it was to write device drivers, disk defragmenters and file utilities for this platform. Perhaps a future article will go into more detail.
Article written by a former VAX Operator
|
HomePage |
|
