SDS 930
Encyclopedia
The SDS 930 was a commercial computer
using bipolar junction transistor
s sold by Scientific Data Systems
.
It was announced in December 1963, with first installations in June 1964.
) magnetic core memory, and the IO unit. Two's complement
integer arithmetic was used. The machine had integer multiply and divide, but no floating point hardware. An optional correlation and filtering unit (CFE) could be added, which was capable of very fast floating point multiply-add operations (primarily intended for digital signal processing applications).
A free-standing console was also provided, which included binary displays of the machine's registers and switches to boot and debug programs. User input was by a Teletype
Model 35 ASR unit and a high-speed paper tape reader (300 cps). Most systems included at least two magnetic tape drives, operating at up to 75 inches/second at 800 bpi. The normal variety of peripherals was also available, including magnetic drum units, card readers and punches, and an extensive set of analog-digital/digital-analog conversion devices. A (vector mode) graphic display unit was also available, but it did not include a means of keyboard input.
The SDS 930 was a typical small to medium scale scientific computer at the time. Speed was good for its cost, but with an integer add time of 3.5 microseconds, it was not in the same league as the scientific workhorses of the day (the CDC 6600
, for example). A well equipped 930 could easily exceed 10 cabinets and require a 300-500 sq. ft. climate controlled room. The price of such a system in 1966 would be in the neighborhood of $500K.
Programming languages available included FORTRAN II, ALGOL 60, and the assembly language known as Metasymbol. The FORTRAN system was very compact, having been designed and implemented by Digitek for SDS to compile and run in 4,096 word SDS 900 series machines. To do anything useful in such small memory space, the compiler relied on an SDS architectural feature known as Programmed OPeratorS, or POPS. This feature consisted of a single bit in the instruction word that caused the machine to "mark place and branch" to the memory address of the instruction code value plus 100 (octal). As a result, pseudo instructions could be defined and implemented yielding very compact special-purpose code. Both the FORTRAN compiler and runtime took advantage of this capability.
Towards the end of the SDS 930's market lifetime a real-time operating system was introduced, and it included a FORTRAN IV compiler. Neither the operating system nor the compiler were used heavily by customers. Many organizations modified and enhanced the 930's hardware. Project Genie
at the University of California, Berkeley
, added hardware to permit time-sharing with the Berkeley Timesharing System
. These changes later formed the basis for the SDS 940
.
Other operating systems were also written for the machine by customers, including Arachnid (Spider) at the University of Texas at Austin.
SDS 930s could be found at most of the major US government labs at the time, including Los Alamos Scientific Laboratory. Early Flight simulators used the SDS 930, because of its hardware integer multiply and divide capability and its real-time data acquisition and control peripheral modules. The machines were particularly well-suited to this and other kinds of data acquisition and real-time analysis, as well as to serving as a digital control system for analog-hybrid systems.
By 1974 estimates, there were about 200 SDS-930/940/945 computers still installed.
Computer
A computer is a programmable machine designed to sequentially and automatically carry out a sequence of arithmetic or logical operations. The particular sequence of operations can be changed readily, allowing the computer to solve more than one kind of problem...
using bipolar junction transistor
Bipolar junction transistor
|- align = "center"| || PNP|- align = "center"| || NPNA bipolar transistor is a three-terminal electronic device constructed of doped semiconductor material and may be used in amplifying or switching applications. Bipolar transistors are so named because their operation involves both electrons...
s sold by Scientific Data Systems
Scientific Data Systems
Scientific Data Systems, or SDS, was an American computer company founded in September 1961 by Max Palevsky, a veteran of Packard Bell and Bendix, along with eleven other computer scientists. SDS was an early adopter of integrated circuits in computer design and the first to employ silicon...
.
It was announced in December 1963, with first installations in June 1964.
Description
An SDS 930 system consisted of at least three standard (30 cu. ft.) cabinets, comprising the arithmetic and logic unit, at least 8,192 words (24-bit + simple parity bitParity bit
A parity bit is a bit that is added to ensure that the number of bits with the value one in a set of bits is even or odd. Parity bits are used as the simplest form of error detecting code....
) magnetic core memory, and the IO unit. Two's complement
Two's complement
The two's complement of a binary number is defined as the value obtained by subtracting the number from a large power of two...
integer arithmetic was used. The machine had integer multiply and divide, but no floating point hardware. An optional correlation and filtering unit (CFE) could be added, which was capable of very fast floating point multiply-add operations (primarily intended for digital signal processing applications).
A free-standing console was also provided, which included binary displays of the machine's registers and switches to boot and debug programs. User input was by a Teletype
Teleprinter
A teleprinter is a electromechanical typewriter that can be used to communicate typed messages from point to point and point to multipoint over a variety of communication channels that range from a simple electrical connection, such as a pair of wires, to the use of radio and microwave as the...
Model 35 ASR unit and a high-speed paper tape reader (300 cps). Most systems included at least two magnetic tape drives, operating at up to 75 inches/second at 800 bpi. The normal variety of peripherals was also available, including magnetic drum units, card readers and punches, and an extensive set of analog-digital/digital-analog conversion devices. A (vector mode) graphic display unit was also available, but it did not include a means of keyboard input.
The SDS 930 was a typical small to medium scale scientific computer at the time. Speed was good for its cost, but with an integer add time of 3.5 microseconds, it was not in the same league as the scientific workhorses of the day (the CDC 6600
CDC 6600
The CDC 6600 was a mainframe computer from Control Data Corporation, first delivered in 1964. It is generally considered to be the first successful supercomputer, outperforming its fastest predecessor, IBM 7030 Stretch, by about three times...
, for example). A well equipped 930 could easily exceed 10 cabinets and require a 300-500 sq. ft. climate controlled room. The price of such a system in 1966 would be in the neighborhood of $500K.
Programming languages available included FORTRAN II, ALGOL 60, and the assembly language known as Metasymbol. The FORTRAN system was very compact, having been designed and implemented by Digitek for SDS to compile and run in 4,096 word SDS 900 series machines. To do anything useful in such small memory space, the compiler relied on an SDS architectural feature known as Programmed OPeratorS, or POPS. This feature consisted of a single bit in the instruction word that caused the machine to "mark place and branch" to the memory address of the instruction code value plus 100 (octal). As a result, pseudo instructions could be defined and implemented yielding very compact special-purpose code. Both the FORTRAN compiler and runtime took advantage of this capability.
Towards the end of the SDS 930's market lifetime a real-time operating system was introduced, and it included a FORTRAN IV compiler. Neither the operating system nor the compiler were used heavily by customers. Many organizations modified and enhanced the 930's hardware. Project Genie
Project Genie
Project Genie was a computer research project started in 1964 at the University of California, Berkeley.It produced an early time-sharing system including the Berkeley Timesharing System, which was then commercialized as the SDS 940.-History:...
at the University of California, Berkeley
University of California, Berkeley
The University of California, Berkeley , is a teaching and research university established in 1868 and located in Berkeley, California, USA...
, added hardware to permit time-sharing with the Berkeley Timesharing System
Berkeley Timesharing System
The Berkeley Timesharing System was a pioneering time-sharing operating system implemented between 1964 and 1967 at the University of California, Berkeley...
. These changes later formed the basis for the SDS 940
SDS 940
The SDS 940 was Scientific Data Systems' first machine designed to support time sharing directly, and was based on the SDS 930's 24-bit CPU built primarily of integrated circuits. It was announced in February 1966 and shipped in April, becoming a major part of Tymshare's expansion during the 1960s...
.
Other operating systems were also written for the machine by customers, including Arachnid (Spider) at the University of Texas at Austin.
SDS 930s could be found at most of the major US government labs at the time, including Los Alamos Scientific Laboratory. Early Flight simulators used the SDS 930, because of its hardware integer multiply and divide capability and its real-time data acquisition and control peripheral modules. The machines were particularly well-suited to this and other kinds of data acquisition and real-time analysis, as well as to serving as a digital control system for analog-hybrid systems.
By 1974 estimates, there were about 200 SDS-930/940/945 computers still installed.