Türkçe ansiklopedi, sözlük, genel başvuru ve bilgi sitesi   
  		  Yardım
  Rastgele    

Unit Record Equipment

Before the advent of electronic computers, data processing was performed using electromechanical devices called unit record equipment, electric accounting machines (EAM) or tabulating machines. A data processing shop would have at least one of most of the machine types. Data processing consisted of feeding decks of punch cards through the various machines in a carefully choreographed progression. The flow of card decks between the machines was typically hand-drawn on large sheets of paper using standardised symbols for the various functions.

Unit record machines were as ubiquitous in industry and government in the first half of the twentieth century as computers became in the second half. They allowed large volume, sophisticated, data-processing tasks to be accomplished long before modern (electronic) computers were invented. This data processing was accomplished by processing decks of punched cards through various unit record machines in a carefully choreographed progression. This progression, or flow, from machine to machine was often planned and documented with drawings that used standardised symbols for the various machine functions – drawings that today would be called flowcharts. The machines all had high-speed mechanical feeders to process from around one hundred cards per minute, to 2,000 cards per minute, sensing punched holes with either electrical or optical sensors. The operation of many machines was directed by the use of a removable control panel. Initially all machines were constructed using electromechanical counters and relays. Electronic components were introduced on some machines beginning in the late 1940s.

History

Herman Hollerith developed punched card and unit record technology for the 1890 census and founded the Tabulating Machine Company (1896) which was one of three companies that merged to form Computing Tabulating Recording Corporation (CTR), later renamed IBM. IBM manufactured and marketed a variety of unit record machines for creating, sorting, and tabulating punched cards, even after expanding into computers in the late 1950s. IBM developed punch card technology into a powerful tool for business data-processing and produced an extensive line of general-purpose unit record machines. By 1950, the IBM card and IBM unit record machines had become ubiquitous in industry and government. The warning often printed on cards that were to be individually handled, "Do not fold, spindle or mutilate," became a motto for the post-World War II era (even though many people had no idea what spindle meant). The largest supplier of unit record equipment was IBM and this article largely reflects IBM practice and terminology.

Punched cards

The basic unit of data storage was the 80-column punched card. Each punched column represented a single digit, letter or special character. Data values consisted of a field of adjacent columns. An employee number might occupy 5 columns; hourly pay rate, 3 columns; hours actually worked in a given week, 2 columns; department number 3 columns; project charge code 6 columns and so on.

Keypunching

Enlarge picture
A key punch (IBM 029).
Original data was usually punched into cards by workers, often women, known as key punch operators. Their work was often checked by a second operator using a verifier machine. Cards were also produced automatically by various unit record machines and later by computer output devices.

Sorting

A major activity in any unit record shop was sorting decks of punch card into the proper order as determined by information punched in the card. The same deck might be sorted differently depending on the processing step. Sorters, like the IBM 80 series Card Sorters, sorted an input deck into one of 13 output bins depending on which hole was punched in a selected column. The 13th bin was for blanks and rejects. Sorting an input deck into ascending sequence on a multiple column field, such as an employee number, was done by a radix sort.

Data processing tasks typically ran on a daily batch processing cycle. All the data cards punched during the day were sorted and merged with a master deck, which was then tabulated.

Tabulating

Enlarge picture
An IBM 407 at US Army's Redstone Arsenal in 1961.
Reports and summary data were generated by accounting or tabulating machines. The sorted deck was fed through the tabulating machine and each card was printed on its own line. Selected fields from each card were added to the value of one of several counters. At some signal, say a card with a special punch indicating it was a master card, a summary line would be produced containing the summed values.

For more details on this topic, see IBM 407.


For many applications, the volume of paper produced by tabulators required other machines, not considered to be unit record machines, to ease paper handling.

Card punching

Enlarge picture
A reproducing punch, like this one from IBM, could make exact copies of a deck of cards.
Card punching machines included: Later "document origination machines" such as the IBM 519 could perform all of the above operations.

Collating and interpreting

A collator had two input hoppers and four or more output hoppers. These machines could merge or match card decks based on the control panel's program. An interpreter would print characters equivalent to the EBCDIC values of columns along the top of the card. The columns to be printed could be selected and even reordered, based on the machine's control panel wiring.

Transmission Of Punched Card Data

Electrical transmission of punch card data was invented in the early 1930's. The device was called an Electrical Remote Control of Office Machines and was assigned to IBM. Inventors were Joseph C.Bolt of Boston & Curt I. Johnson; Worcester, Mass. assors to the Tabulating Machine Co., Endicott, NY. The Distance Control Device received a US patent in Aug.9,1932: pat# 1,870,230. Letters from IBM talk about filling in Canada in 9/15/1931.

Processing Punched Tape

The IBM 046 Tape-to-Card Punch and IBM 047 Tape-to-Card Printing Punch were almost identical, with the exception of the printing mechanism. These machines read data from punched paper tape and punched that data into punched cards.

See Punched tape.

Programming

Enlarge picture
IBM 402 Accounting Machine plug-board.
The operation of most unit record equipment (except for sorters) was directed by a plug-board control panel (IBM did not use the term "programming" for these machines). The panels had a matrix of holes organized into groups. Wires with metal ferrules at each end were place in the holes to make connections. The output from some card column positions might be fed into a tabulating machine's counter, for example. A shop would typically have separate plug-boards for each task a machine was used for.

Unit record equipment in the computer age

Early computer installations used punched cards for program entry and storage. A typical corporate or university computer lab would have a room full of key punch machines for programmer use. An IBM 407 Accounting Machine might be set up to allow newly created or edited programs to be listed (printed out on fan-fold paper) for proof reading. An IBM 519 might be provided to reproduce program decks for backup. The 519 could also punch sequential numbers in columns 73-80 of COBOL or Fortran program decks. Those languages and others did not use those columns; the use of only 72 columns is a tradition tracing back to the IBM 704 card reader. An IBM 80 series sorter would be used to put things back in order if a sequenced deck was dropped. A quicker, but less effective, protection against dropped card decks was drawing a diagonal line across the top of the deck with a marking pen.

Early mid-sized commercial computers, such as the IBM 1401 were designed to work with punch card operations and allowed more complex reporting. However many shops soon began using magnetic tape as their primary storage medium, using cards primarily for data input.

Many organizations were loath to alter systems that were working, so production unit record installations remained in operation long after computers offered faster and more cost effective solutions. Specialized uses of punch cards, including toll collection, microfilm aperture cards, and punch card voting, keep unit record equipment in use into the twenty-first century.

The IBM System/3, the original ancestor of the entire IBM midrange computer product line, was developed as a replacement for plugboard-programmable unit record machines.

Guide to the unit record equipment articles

See also

References

Typical machines for unit record processing were:

Keypunching Sorting Collating Tabulating Card Punching Interpreting Calculating Statistical The following provide summaries of a number of unit record machines.

Notes

External links

computer is a machine which manipulates data according to a list of instructions.

Computers take numerous physical forms. The first devices that resemble modern computers date to the mid-20th century (around 1940 - 1941), although the computer concept and various machines
..... Click the link for more information.
punch card or punched card (or punchcard or Hollerith card or IBM card), is a piece of stiff paper that contains digital information represented by the presence or absence of holes in predefined positions.
..... Click the link for more information.
twentieth century of the Common Era began on January 1, 1901 and ended on December 31, 2000, according to the Gregorian calendar. Some historians consider the era from about 1914 to 1991 to be the Short Twentieth Century.
..... Click the link for more information.
computer is a machine which manipulates data according to a list of instructions.

Computers take numerous physical forms. The first devices that resemble modern computers date to the mid-20th century (around 1940 - 1941), although the computer concept and various machines
..... Click the link for more information.
Data processing is any computer process that converts data into information or knowledge. The processing is usually assumed to be automated and running on a computer. Because data are most useful when well-presented and actually informative
..... Click the link for more information.
punch card or punched card (or punchcard or Hollerith card or IBM card), is a piece of stiff paper that contains digital information represented by the presence or absence of holes in predefined positions.
..... Click the link for more information.
flowchart (also spelled flow-chart and flow chart) is a schematic representation of an algorithm or a process. A flowchart is one of the seven basic tools of quality control, which also includes the histogram, Pareto chart, check sheet, control chart, cause-and-effect
..... Click the link for more information.
plug-board, or, more formally, a control panel, was a device used to direct the operation of unit record equipment (and some early computers) built by IBM and other companies during the punch card era.
..... Click the link for more information.
Herman Hollerith (February 29, 1860 – November 17, 1929) was a German-American statistician who developed a mechanical tabulator based on punched cards in order to rapidly tabulate statistics from millions of pieces of data.
..... Click the link for more information.
18th century - 19th century - 20th century
1860s  1870s  1880s  - 1890s -  1900s  1910s  1920s
1893 1894 1895 - 1896 - 1897 1898 1899

:
Subjects:     Archaeology - Architecture -
..... Click the link for more information.
International Business Machines Corporation

Public (NYSE:  IBM )
Founded 1889, incorporated 1911
Headquarters Armonk, New York, USA

Key people Samuel J.
..... Click the link for more information.
worldwide view.


2nd millennium
Centuries: 19th century - 20th century - 21st century

1920s 1930s 1940s - 1950s - 1960s 1970s 1980s
1950 1951 1952 1953 1954
1955 1956 1957 1958 1959

- -
- The 1950s
..... Click the link for more information.
Allied powers:
 Soviet Union
 United States
 United Kingdom
 China
 France
...et al. Axis powers:
 Germany
 Japan
 Italy
...et al.
..... Click the link for more information.
A spindle (or colloquially, a spike) is an upright spike used to hold papers waiting for processing. "Spindling" or "spiking" was the act of spearing a paper document onto the spike. Spindling of Hollerith cards is unwise as it can render the cards unreadable.
..... Click the link for more information.
International Business Machines Corporation

Public (NYSE:  IBM )
Founded 1889, incorporated 1911
Headquarters Armonk, New York, USA

Key people Samuel J.
..... Click the link for more information.
punch card or punched card (or punchcard or Hollerith card or IBM card), is a piece of stiff paper that contains digital information represented by the presence or absence of holes in predefined positions.
..... Click the link for more information.
A key punch is a device for entering data into punched cards by precisely punching holes at locations designated by the keys struck by the operator. Early keypunches were manual devices.
..... Click the link for more information.
In computer science and mathematics, a sorting algorithm is an algorithm that puts elements of a list in a certain order. The most-used orders are numerical order and lexicographical order.
..... Click the link for more information.
IBM 80 Electric Punched Card Sorting Machine Introduced by IBM in 1925. This sorter was almost twice the speed of the older Hollerith 70 vertical sorter and used an entirely new magnetically operated horizontal sorting design.
..... Click the link for more information.
Bucket sort, or bin sort, is a sorting algorithm that works by partitioning an array into a finite number of buckets. Each bucket is then sorted individually, either using a different sorting algorithm, or by recursively applying the bucket sorting algorithm.
..... Click the link for more information.
In computer science, radix sort is a sorting algorithm that sorts integers by processing individual digits. Because integers can represent strings of characters (e.g., names or dates) and specially formatted floating point numbers, radix sort is not limited to integers.
..... Click the link for more information.
Merge algorithms are a family of algorithms that run sequentially over multiple sorted lists, typically producing more sorted lists as output. This is well-suited for machines with tape drives.
..... Click the link for more information.
tabulating machine was a machine designed to assist in tabulations. Invented by Herman Hollerith, the machine was developed to help process data for the 1890 U.S. Census.

The term "Super Computing" was first used by the New York World newspaper in 1929[1]
..... Click the link for more information.
IBM 407 Accounting Machine, introduced in 1949, was the culmination of a long line of IBM tabulating machines dating back to the days of Herman Hollerith (see the tabulators and accounting machines in List of IBM products#Unit record equipment).
..... Click the link for more information.
The IBM 519 Electric Document Originating Machine, introduced in 1946, was the last in a series of unit record machines designed for automated production of punch cards. It could reproduce all or parts of the information on a set of cards; copy the information from a master card
..... Click the link for more information.
Extended Binary Coded Decimal Interchange Code (EBCDIC) is an 8-bit character encoding (code page) used on IBM mainframe operating systems, like z/OS, OS/390, VM and VSE, as well as IBM minicomputer operating systems like OS/400 and i5/OS (see also Binary Coded Decimal).
..... Click the link for more information.
Punched tape or paper tape is a largely obsolete form of data storage, consisting of a long strip of paper in which holes are punched to store data. It was widely used during much of the twentieth century for teleprinter communication, and later as a storage medium for
..... Click the link for more information.
plug-board, or, more formally, a control panel, was a device used to direct the operation of unit record equipment (and some early computers) built by IBM and other companies during the punch card era.
..... Click the link for more information.
IBM 407 Accounting Machine, introduced in 1949, was the culmination of a long line of IBM tabulating machines dating back to the days of Herman Hollerith (see the tabulators and accounting machines in List of IBM products#Unit record equipment).
..... Click the link for more information.
The IBM 519 Electric Document Originating Machine, introduced in 1946, was the last in a series of unit record machines designed for automated production of punch cards. It could reproduce all or parts of the information on a set of cards; copy the information from a master card
..... Click the link for more information.


This article is copied from an article on Wikipedia.org - the free encyclopedia created and edited by online user community. The text was not checked or edited by anyone on our staff. Although the vast majority of the wikipedia encyclopedia articles provide accurate and timely information please do not assume the accuracy of any particular article. This article is distributed under the terms of GNU Free Documentation License.