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

General Electric General Electric Company (GE) is an American multinational conglomerate founded in 1892, and incorporated in New York state and headquartered in Boston. The company operated in sectors including healthcare, aviation, power, renewable ene ...

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

data communications Data transmission and data reception or, more broadly, data communication or digital communications is the transfer and reception of data in the form of a digital bitstream or a digitized analog signal transmitted over a point-to-point or ...

. 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 free standing installations beginning in 1963 were

Chrysler Corporation Stellantis North America (officially FCA US and formerly Chrysler ()) is one of the " Big Three" automobile manufacturers in the United States, headquartered in Auburn Hills, Michigan. It is the American subsidiary of the multinational automotiv ...

message switching systems replacing

Teletype A teleprinter (teletypewriter, teletype or TTY) is an electromechanical device that can be used to send and receive typed messages through various communications channels, in both point-to-point and point-to-multipoint configurations. Init ...

punched tape systems. In 1964, acting as a front end processor along with an interface to the GE-225 computer a professor at

Dartmouth College Dartmouth College (; ) is a private research university in Hanover, New Hampshire. Established in 1769 by Eleazar Wheelock, it is one of the nine colonial colleges chartered before the American Revolution. Although founded to educate Native ...

developed the

BASIC BASIC (Beginners' All-purpose Symbolic Instruction Code) is a family of general-purpose, high-level programming languages designed for ease of use. The original version was created by John G. Kemeny and Thomas E. Kurtz at Dartmouth College ...

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

magnetic-core memory Magnetic-core memory was the predominant form of random-access computer memory for 20 years between about 1955 and 1975. Such memory is often just called core memory, or, informally, core. Core memory uses toroids (rings) of a hard magnet ...

with a cycle time of 6.94 μs. The

word A word is a basic element of language that carries an objective or practical 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 conse ...

size was 18 bits and memory was available in sizes of 4K, 8K, or 16K words. The system could attach up to 128

asynchronous Asynchrony is the state of not being in synchronization. Asynchrony or asynchronous may refer to: Electronics and computing * Asynchrony (computer programming), the occurrence of events independent of the main program flow, and ways to deal wit ...

terminal Terminal may refer to: Computing Hardware * Terminal (electronics), a device for joining electrical circuits together * Terminal (telecommunication), a device communicating over a line * Computer terminal, a set of primary input and output devi ...

s, nominally at speeds of up to "3000 bits per second" (bps), but usually limited to the 300 bps supported by standard common-carrier facilities of the time, such as

Bell 103 modem The Bell 103 modem or Bell 103 dataset was the second commercial modem for computers, released by AT&T Corporation in 1962. It allowed digital data to be transmitted over regular unconditioned telephone lines at a speed of 300 bits per second. I ...

. The DATANET-30 could also operate in synchronous mode at speeds up to 2400 bps. 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 and allows certain hardware subsystems to access main system memory independently of the central processing unit (CPU). Without DMA, when the CPU is using programmed input/output, it is ...

(DMA). It could also attach to the

I/O channel In computing, channel I/O is a high-performance input/output (I/O) architecture that is implemented in various forms on a number of computer architectures, especially on mainframe computers. In the past, channels were generally implemented with cu ...

of a

GE-400 series The GE-400 series were time-sharing Information Systems computers by General Electric introduced in 1964 and shipped until 1968. System description The GE-400 series (Compatibles/400) came in models: 415, 425, 435 (1964), 455 and 465. GE-400 syst ...

, or

GE-600 series The GE-600 series was a family of 36-bit 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 1990s as the division ...

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

peripheral A peripheral or peripheral device is an auxiliary device used to put information into and get information out of a computer. The term ''peripheral device'' refers to all hardware components that are attached to a computer and are controlled by the ...

s such as

disk storage Disk storage (also sometimes called drive storage) is a general category of storage mechanisms where data is recorded by various electronic, magnetic, optical, or mechanical changes to a surface layer of one or more rotating disks. A disk drive is ...

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 magnet ...

, or a

line printer A line printer prints one entire line of text before advancing to another line. Most early line printers were impact printers. Line printers are mostly associated with unit record equipment and the early days of digital computing, but the ...

. The system was also a general purpose computer, with a number of special-purpose

hardware register In digital electronics, especially computing, hardware registers are circuits typically composed of flip flops, often with many characteristics similar to memory, such as: * The ability to read or write multiple bits at a time, and * Using an ...

s. The instruction set contained 78 instructions.

Assembler Assembler may refer to: Arts and media * Nobukazu Takemura, avant-garde electronic musician, stage name Assembler * Assemblers, a fictional race in the ''Star Wars'' universe * Assemblers, an alternative name of the superhero group Champions of ...

s 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 {{comp-hardware-stub