The DATANET-30, or DN-30 for short, was a computer manufactured by

General Electric General Electric Company (GE) was an American Multinational corporation, multinational Conglomerate (company), conglomerate founded in 1892, incorporated in the New York (state), state of New York and headquartered in Boston. Over the year ...

designed in 1961-1963 to be used as a communications computer. It was later used as a front-end processor for

data communications Data communication, including data transmission and data reception, is the transfer of data, signal transmission, transmitted and received over a Point-to-point (telecommunications), point-to-point or point-to-multipoint communication chann ...

. It became the first front end communications computer. The names on the patent were Don Birmingham, Bob McKenzie, Bud Pine, and Bill Hill. The first freestanding installations beginning in 1963 were Chrysler Corporation message switching systems, replacing Teletype punched tape systems. In 1964, acting as a front end processor along with an interface to the

GE-225 file:GE_210_advertisement.jpg, GE 210 advertisement from 1960 The GE-200 series was a family of small Mainframe computer, mainframe computers of the 1960s, built by General Electric (GE). GE marketing called the line ''Compatibles/200'' (GE-205/21 ...

computer, a professor at

Dartmouth College Dartmouth College ( ) is a Private university, private Ivy League research university in Hanover, New Hampshire, United States. Established in 1769 by Eleazar Wheelock, Dartmouth is one of the nine colonial colleges chartered before the America ...

developed the

BASIC Basic or BASIC may refer to: Science and technology * BASIC, a computer programming language * Basic (chemistry), having the properties of a base * Basic access authentication, in HTTP Entertainment * Basic (film), ''Basic'' (film), a 2003 film ...

programming language. Multiple teletype units were attached to be the first time-sharing system. The DATANET-30 used

magnetic-core memory In computing, magnetic-core memory is a form of random-access memory. It predominated for roughly 20 years between 1955 and 1975, and is often just called core memory, or, informally, core. Core memory uses toroids (rings) of a hard magneti ...

with a cycle time of 6.94 μs. The

word A word is a basic element of language that carries semantics, meaning, can be used on its own, and is uninterruptible. Despite the fact that language speakers often have an intuitive grasp of what a word is, there is no consensus among linguist ...

size was 18 bits and memory was available in sizes of 4K, 8K, or 16K words. The system could attach up to 128 asynchronous terminals, nominally at speeds of up to "3000 bits per second" (bit/s), but usually limited to the 300 bit/s supported by standard common-carrier facilities of the time, such as the Bell 103 modem. The DATANET-30 could also operate in synchronous mode at speeds up to 2400 bit/s. A ''Computer Interface Unit'' allowed the DATANET-30 to communicate with a GE-200 series computer using

direct memory access Direct memory access (DMA) is a feature of computer systems that allows certain hardware subsystems to access main system computer memory, memory independently of the central processing unit (CPU). Without DMA, when the CPU is using programmed i ...

(DMA). It could also attach to the I/O channel of a GE-400 series, or

GE-600 series The GE-600 series is a family of 36-bit Mainframe computer, mainframe computers originating in the 1960s, built by General Electric (GE). When GE left the mainframe business, the line was sold to Honeywell, which built similar systems into the 1 ...

system. An optional attachment allowed the DATANET-30 to attach GE-200 series

peripheral A peripheral device, or simply peripheral, is an auxiliary hardware device that a computer uses to transfer information externally. A peripheral is a hardware component that is accessible to and controlled by a computer but is not a core compo ...

s such as

disk storage Disc or disk may refer to: * Disk (mathematics) In geometry, a disk (Spelling of disc, also spelled disc) is the region in a plane (geometry), plane bounded by a circle. A disk is said to be ''closed'' if it contains the circle that constitut ...

magnetic tape Magnetic tape is a medium for magnetic storage made of a thin, magnetizable coating on a long, narrow strip of plastic film. It was developed in Germany in 1928, based on the earlier magnetic wire recording from Denmark. Devices that use magnetic ...

, or a

line printer A line printer Printer (computing), prints one entire line of text before advancing to another line. Most early line printers were printer (computing)#Impact printers, impact printers. Line printers are mostly associated with unit record eq ...

. The system was also a general purpose computer, with a number of special-purpose hardware registers. The instruction set contained 78 instructions. Assemblers were provided for the DATANET-30, one of which could run on the DATANET itself and one on the GE-225.

References

External links

Photo of DATANET-30 at Computer History Museum
General Electric mainframe computers Transistorized computers Networking hardware Computer-related introductions in 1965 18-bit computers {{mainframe-compu-stub