Punched card input/output

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An IBM 650 computer, introduced in 1953, came with the IBM 533 Card Reader/Punch, right. At many IBM 650 installations, punched cards were the only input and output medium.
IBM 711 card reader on an IBM 704 computer at NASA in 1957
The popular IBM 1401, introduced in 1959 featured a fast card reader/punch, the IBM 1402, left and a fast line printer, the IBM 1403, right
IBM 711 card readers, far left and foreground, attached to dual IBM 7090s at NASA Mission Control in 1962.
An IBM 2540 Card Reader Punch at the University of Michigan computer center in 1968
Punched card reader on an IBM System/360 Model 20
IBM System/3, announced in 1969 introduced a new, smaller punched card and a combined reader/punch/sorter, right
IBM 7070 with IBM 7501 Console Card Reader, right, based in the IBM 026 keypunch

A computer punched card reader or just computer card reader is a computer input device used to read executable computer programs and data from punched cards under computer control. A computer card punch is a computer output device that punches holes in cards under computer control. Sometimes computer card readers were combined with computer card punches and, later, other devices to form multifunction machines.

Most early computers, such as the ENIAC, and the IBM NORC, provided for punched card input/output.[1] Card readers and punches, either connected to computers or in off-line card to/from magnetic tape configurations, were ubiquitous through the mid-1970s.

Punched cards had been in use since the 1890s; their technology was mature and reliable. Card readers and punches developed for punched card machines were readily adaptable for computer use.[2] Businesses were familiar with storing data on punched cards and keypunch machines were widely employed. Punched cards were a better fit than other 1950s technologies, such as magnetic tape, for some computer applications as individual cards could easily be updated without having to access a computer.

Card readers/punches[edit]



Documation Inc., of Melbourne, Florida, made card readers for minicomputers in the 1970s:

  • M-200 card reader, 300 cards/minute[3] also sold by DEC as the CR-11 card reader for the PDP-11[4]
  • M-1000-L card reader 1000 cards/minute[5]


See List of IBM products


See also[edit]

  • Plugboard discusses how early card readers worked in some detail.