Simon (computer)
Encyclopedia
Simon was the name given to the first "personal computer
" of history, a project developed by Edmund Berkeley
and presented in a thirteen articles series issued in Radio-Electronics
magazine, from October 1950. Although there were far more advanced machines at the time of its construction, the Simon represented the first experience of building an automatic simple digital computer, for educational purposes. In 1950, it was sold for US
$600.
In November 1950, Berkeley wrote an article entitled Simple Simon for Scientific American
magazine, which was a description of the digital computing principles for the general public. Despite Simon's extreme lack of resources (it was able to represent only the numbers 0, 1, 2 and 3), Berkeley stated on page 40 that the machine "possessed the two unique properties that define any true mechanical brain: it can transfer information automatically from any one of its "registers" to any other, and it can perform reasoning operations of indefinite length". Berkeley concluded his article anticipating the future:
was based on relay
s. The programs were run from a standard paper tape
with five rows of holes for data. The registers and ALU
could store only 2 bit
. The data entry was made through the punched paper or by five keys on the front panel
of the machine. The output was provided by five lamps.
The punched tape served not only for data entry, but also as a memory for the machine. The instructions were carried out in sequence, as they were read from the tape. The machine was able to perform four operations: addition, negation, greater than, and selection.
Personal computer
A personal computer is any general-purpose computer whose size, capabilities, and original sales price make it useful for individuals, and which is intended to be operated directly by an end-user with no intervening computer operator...
" of history, a project developed by Edmund Berkeley
Edmund Berkeley
Edmund Callis Berkeley was an American computer scientist who co-founded the Association for Computing Machinery in 1947. He was also a social activist who worked to achieve conditions that might minimize the threat of nuclear war.-Biography:Berkeley received a BA in Mathematics and Logic from...
and presented in a thirteen articles series issued in Radio-Electronics
Radio-Electronics
Radio-Electronics was an American electronics magazine that was published under various titles from 1929 to 2003. Hugo Gernsback started it as Radio-Craft in July 1929. The title was changed to Radio-Electronics in October 1948 and again to Electronics Now in July 1992. In January 2000 it was...
magazine, from October 1950. Although there were far more advanced machines at the time of its construction, the Simon represented the first experience of building an automatic simple digital computer, for educational purposes. In 1950, it was sold for US
United States dollar
The United States dollar , also referred to as the American dollar, is the official currency of the United States of America. It is divided into 100 smaller units called cents or pennies....
$600.
History
The "Simon project" arose as a result of the Berkeley's book Giant Brains, or Machines That Think, published in November 1949. There, the author said:In November 1950, Berkeley wrote an article entitled Simple Simon for Scientific American
Scientific American
Scientific American is a popular science magazine. It is notable for its long history of presenting science monthly to an educated but not necessarily scientific public, through its careful attention to the clarity of its text as well as the quality of its specially commissioned color graphics...
magazine, which was a description of the digital computing principles for the general public. Despite Simon's extreme lack of resources (it was able to represent only the numbers 0, 1, 2 and 3), Berkeley stated on page 40 that the machine "possessed the two unique properties that define any true mechanical brain: it can transfer information automatically from any one of its "registers" to any other, and it can perform reasoning operations of indefinite length". Berkeley concluded his article anticipating the future:
Technical specifications
The Simon's architectureComputer architecture
In computer science and engineering, computer architecture is the practical art of selecting and interconnecting hardware components to create computers that meet functional, performance and cost goals and the formal modelling of those systems....
was based on relay
Relay
A relay is an electrically operated switch. Many relays use an electromagnet to operate a switching mechanism mechanically, but other operating principles are also used. Relays are used where it is necessary to control a circuit by a low-power signal , or where several circuits must be controlled...
s. The programs were run from a standard paper tape
Punched tape
Punched tape or paper tape is an obsolete form of data storage, consisting of a long strip of paper in which holes are punched to store data...
with five rows of holes for data. The registers and ALU
Arithmetic logic unit
In computing, an arithmetic logic unit is a digital circuit that performs arithmetic and logical operations.The ALU is a fundamental building block of the central processing unit of a computer, and even the simplest microprocessors contain one for purposes such as maintaining timers...
could store only 2 bit
Bit
A bit is the basic unit of information in computing and telecommunications; it is the amount of information stored by a digital device or other physical system that exists in one of two possible distinct states...
. The data entry was made through the punched paper or by five keys on the front panel
Front panel
A front panel was used on early electronic computers to display and allow the alteration of the state of the machine's internal registers and memory. The front panel usually consisted of arrays of indicator lamps, toggle switches, and push buttons mounted on a sheet metal face plate...
of the machine. The output was provided by five lamps.
The punched tape served not only for data entry, but also as a memory for the machine. The instructions were carried out in sequence, as they were read from the tape. The machine was able to perform four operations: addition, negation, greater than, and selection.