The text-only

monochrome A monochrome or monochromatic image, object or palette is composed of one color (or values of one color). Images using only shades of grey are called grayscale (typically digital) or black-and-white (typically analog). In physics, monochrom ...

IBM 2260 cathode-ray tube (CRT)

video display terminal A computer terminal is an electronic or electromechanical hardware device that can be used for entering data into, and transcribing data from, a computer or a computing system. The teletype was an example of an early-day hard-copy terminal a ...

(Display Station) plus

keyboard Keyboard may refer to: Text input * Keyboard, part of a typewriter * Computer keyboard ** Keyboard layout, the software control of computer keyboards and their mapping ** Keyboard technology, computer keyboard hardware and firmware Music * Musi ...

was a 1964 predecessor to the more-powerful IBM 3270 terminal line which eventually was extended to support color text and graphics. There were three models of 2260. Model 1 displayed 240 characters, formatted as six rows of forty characters. Model 2 displayed 480 characters, formatted as twelve rows of forty characters. Model 3 displayed 960 characters, formatted as twelve rows of eighty characters. A model without a keyboard was available for display-only applications. The eighty character width corresponded to IBM

punch card A punched card (also punch card or punched-card) is a piece of stiff paper that holds digital data represented by the presence or absence of holes in predefined positions. Punched cards were once common in data processing applications or to di ...

format. The IBM 2260 and successor devices were transitional punch-card-to-CRT computer hardware that inspired many

office of the future The office of the future is a concept dating from the 1940s. It is also known as the "paperless office". Memex desk and related machines The first practical office of the future concept was probably the series of machines which were presented in ...

authors to write about the potential of the

paperless office A paperless office (or paper-free office) is a work environment in which the use of paper is eliminated or greatly reduced. This is done by converting documents and other papers into digital form, a process known as digitization. Proponents claim t ...

. The 2260 was a raster display with the unusual property that the

scan line A scan line (also scanline) is one line, or row, in a raster scanning pattern, such as a line of video on a cathode ray tube (CRT) display of a television set or computer monitor. On CRT screens the horizontal scan lines are visually discernible ...

s were vertical they went from top to bottom rather than the more common left to right.Y27-2046-3 Up to twenty-four 2260 terminals were clustered around an IBM 2848 Display Control. The controller could function as a local channel-attached device or as a remote device at up to 2400 bit/s. An optional adapter allowed the attachment of one IBM 1053 printer which was shared by all displays attached to the 2848. The 2848 stored the digital image of screens of information in an

acoustic delay line Delay-line memory is a form of computer memory, now obsolete, that was used on some of the earliest digital computers. Like many modern forms of electronic computer memory, delay-line memory was a refreshable memory, but as opposed to modern r ...

. Before the introduction of integrated circuit chips, the technology was based on discrete-component individual

transistor upright=1.4, gate (G), body (B), source (S) and drain (D) terminals. The gate is separated from the body by an insulating layer (pink). A transistor is a semiconductor device used to Electronic amplifier, amplify or electronic switch, switch ...

s. Mainframe computers used magnetic core memory, which was too expensive for use in

s. The delay line was an unusual mechanical (not electrical) spiral wire with an electromagnet on one end and a torsion rotation detector on the other (which was conceptually similar to a phonograph needle pickup). The central controller system vibrated the electromagnet like an audio-speaker

voice coil A voice coil (consisting of a former, collar, and winding) is the coil of wire attached to the apex of a loudspeaker cone. It provides the motive force to the cone by the reaction of a magnetic field to the current passing through it. The te ...

. A fraction of a second later, the other end of the mechanical wire would vibrate. The vibration was converted to

raster scan A raster scan, or raster scanning, is the rectangular pattern of image capture and reconstruction in television. By analogy, the term is used for raster graphics, the pattern of image storage and transmission used in most computer bitmap image ...

lines and sent to the nearby CRT display. The IBM 2848 delay line was a continuous

electromechanical In engineering, electromechanics combines processes and procedures drawn from electrical engineering and mechanical engineering. Electromechanics focuses on the interaction of electrical and mechanical systems as a whole and how the two systems ...

feedback loop. One effect of the 2848 delay line was that if a heavy person walked next to the controller, or if it was mounted next to a vibration source (like an elevator), digital

bit The bit is the most basic unit of information in computing and digital communications. The name is a portmanteau of binary digit. The bit represents a logical state with one of two possible values. These values are most commonly represente ...

s of screen images would be lost on all of the video displays, which would then be repeated continuously through the feedback loop until a new video display was transmitted to all of the connected terminals. The IBM 2265 attached to an IBM 2845 is a less expensive equivalent to a 2260 attached to a 2848, for users who do not require more than one terminal. The IBM 2260 and 2265 as well as the IBM 2848 were unusual in their usage of the approved, but never published 1965 revision of the

ASCII ASCII ( ), abbreviated from American Standard Code for Information Interchange, is a character encoding standard for electronic communication. ASCII codes represent text in computers, telecommunications equipment, and other devices. Because ...

standard

ASA X3.4-1965 ASCII ( ), abbreviated from American Standard Code for Information Interchange, is a character encoding standard for electronic communication. ASCII codes represent text in computers, telecommunications equipment, and other devices. Because of ...

.
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References

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External links

IBM System/360 Component Description: IBM 2260 Display Station IBM 2848 Display Control

IBM System/36D Component Description: IBM 2265 Display Station Modell IBM 2845 Display Control

IBM computer terminals, 2260 2260 Block-oriented terminal Multimodal interaction History of human–computer interaction