BINAC
Encyclopedia
BINAC, the Binary Automatic Computer, was an early electronic computer
designed for Northrop Aircraft Company
by the Eckert-Mauchly Computer Corporation
in 1949. Eckert and Mauchly, though they had started the design of EDVAC
at the University of Pennsylvania, chose to leave and start EMCC, the first computer company. BINAC was their first product, the first stored-program computer in the US, and the world's first commercial digital computer.
The BINAC was a bit-serial binary
computer with two independent CPU
s, each with its own 512-word acoustic mercury delay line memory
. The CPUs continuously compared results to check for errors caused by hardware failures. It used approximately 700 vacuum tube
s. The 512-word acoustic mercury delay line memories were divided into 16 channels each holding 32 words of 31 bit
s, with an additional 11-bit space between words to allow for circuit delays in switching. The clock rate was 4.25 MHz (1 MHz according to one source) which yielded a word time of about 10 microseconds. The addition time was 800 microseconds and the multiplication time was 1200 microseconds. New programs or data had to be entered manually in octal
using an eight-key keypad. BINAC was significant for being able to perform high-speed arithmetic on binary numbers, with no provisions to store characters or decimal
digits.
The BINAC ran a test program (consisting of 23 instructions) in March 1949, although it wasn't fully functional at the time. Here are early test programs that BINAC ran:
Northrop accepted delivery of BINAC in September 1949. Northrop employees said that BINAC never worked properly after it was delivered, although it had worked at the Eckert-Mauchly workshop. It was able to run some small problems but didn't work well enough to be used as a production machine. Northrop attributed the failures to it not being properly packed for shipping when Northrop picked it up; EMCC said that the problems were due to errors in re-assembly of the machine after shipping. (Northrop, citing security considerations, refused to allow EMCC technicians near the machine after shipping, instead hiring a newly-graduated engineering student to re-assemble it. EMCC said that the fact that it worked at all after this was testimony to the engineering quality of the machine.)
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...
designed for Northrop Aircraft Company
Northrop Corporation
Northrop Corporation was a leading United States aircraft manufacturer from its formation in 1939 until its merger with Grumman to form Northrop Grumman in 1994. The company is known for its development of the flying wing design, although only a few of these have entered service.-History:Jack...
by the Eckert-Mauchly Computer Corporation
Eckert-Mauchly Computer Corporation
The Eckert–Mauchly Computer Corporation was founded by J. Presper Eckert and John Mauchly, and was incorporated on December 22, 1947. After building the ENIAC at the University of Pennsylvania, Eckert and Mauchly formed EMCC to build new computer designs for commercial and military applications...
in 1949. Eckert and Mauchly, though they had started the design of EDVAC
EDVAC
EDVAC was one of the earliest electronic computers. Unlike its predecessor the ENIAC, it was binary rather than decimal, and was a stored program computer....
at the University of Pennsylvania, chose to leave and start EMCC, the first computer company. BINAC was their first product, the first stored-program computer in the US, and the world's first commercial digital computer.
The BINAC was a bit-serial binary
Binary numeral system
The binary numeral system, or base-2 number system, represents numeric values using two symbols, 0 and 1. More specifically, the usual base-2 system is a positional notation with a radix of 2...
computer with two independent CPU
Central processing unit
The central processing unit is the portion of a computer system that carries out the instructions of a computer program, to perform the basic arithmetical, logical, and input/output operations of the system. The CPU plays a role somewhat analogous to the brain in the computer. The term has been in...
s, each with its own 512-word acoustic mercury delay line memory
Computer storage
Computer data storage, often called storage or memory, refers to computer components and recording media that retain digital data. Data storage is one of the core functions and fundamental components of computers....
. The CPUs continuously compared results to check for errors caused by hardware failures. It used approximately 700 vacuum tube
Vacuum tube
In electronics, a vacuum tube, electron tube , or thermionic valve , reduced to simply "tube" or "valve" in everyday parlance, is a device that relies on the flow of electric current through a vacuum...
s. The 512-word acoustic mercury delay line memories were divided into 16 channels each holding 32 words of 31 bit
Bit
A bit is the basic unit of information in computing and telecommunications; it is the amount of information stored by a digital device or other physical system that exists in one of two possible distinct states...
s, with an additional 11-bit space between words to allow for circuit delays in switching. The clock rate was 4.25 MHz (1 MHz according to one source) which yielded a word time of about 10 microseconds. The addition time was 800 microseconds and the multiplication time was 1200 microseconds. New programs or data had to be entered manually in octal
Octal
The octal numeral system, or oct for short, is the base-8 number system, and uses the digits 0 to 7. Numerals can be made from binary numerals by grouping consecutive binary digits into groups of three...
using an eight-key keypad. BINAC was significant for being able to perform high-speed arithmetic on binary numbers, with no provisions to store characters or decimal
Decimal
The decimal numeral system has ten as its base. It is the numerical base most widely used by modern civilizations....
digits.
The BINAC ran a test program (consisting of 23 instructions) in March 1949, although it wasn't fully functional at the time. Here are early test programs that BINAC ran:
- February 7, 1949 - Ran a five-line program to fill the memory from register A.
- February 10, 1949 - Ran a five-line program to check memory.
- February 16, 1949 - Ran a six-line program to fill memory.
- March 7, 1949 - Ran 217 iterations of a 23-line program to compute squares. It was still running correctly when it stopped.
- April 4, 1949 - Ran a fifty-line program to fill memory and check all instructions. It ran for 2.5 hours before encountering an error. Shortly after that it ran for 31.5 hours without error.
Northrop accepted delivery of BINAC in September 1949. Northrop employees said that BINAC never worked properly after it was delivered, although it had worked at the Eckert-Mauchly workshop. It was able to run some small problems but didn't work well enough to be used as a production machine. Northrop attributed the failures to it not being properly packed for shipping when Northrop picked it up; EMCC said that the problems were due to errors in re-assembly of the machine after shipping. (Northrop, citing security considerations, refused to allow EMCC technicians near the machine after shipping, instead hiring a newly-graduated engineering student to re-assemble it. EMCC said that the fact that it worked at all after this was testimony to the engineering quality of the machine.)
External links
- Oral history interview with Isaac Levin Auerbach Oral history interview by Nancy B. Stern, 10 April 1978. Charles Babbage InstituteCharles Babbage InstituteThe Charles Babbage Institute is a research center at the University of Minnesota specializing in the history of information technology, particularly the history since 1935 of digital computing, programming/software, and computer networking....
, University of Minnesota, Minneapolis. Auerbach recounts his experiences at Electronic Control Company (later the Eckert-Mauchly Computer Company) during 1947-1949. He emphasizes the economic and practical infeasibility of the BINAC computer project for Northrop AircraftNorthrop CorporationNorthrop Corporation was a leading United States aircraft manufacturer from its formation in 1939 until its merger with Grumman to form Northrop Grumman in 1994. The company is known for its development of the flying wing design, although only a few of these have entered service.-History:Jack...
. Auerbach also discusses the UNIVACUNIVACUNIVAC is the name of a business unit and division of the Remington Rand company formed by the 1950 purchase of the Eckert-Mauchly Computer Corporation, founded four years earlier by ENIAC inventors J. Presper Eckert and John Mauchly, and the associated line of computers which continues to this day...
, including personalities, politics, and its technical features. The roles of the National Bureau of Standards, Northrop AircraftNorthrop CorporationNorthrop Corporation was a leading United States aircraft manufacturer from its formation in 1939 until its merger with Grumman to form Northrop Grumman in 1994. The company is known for its development of the flying wing design, although only a few of these have entered service.-History:Jack...
, RaytheonRaytheonRaytheon Company is a major American defense contractor and industrial corporation with core manufacturing concentrations in weapons and military and commercial electronics. It was previously involved in corporate and special-mission aircraft until early 2007...
, Remington RandRemington RandRemington Rand was an early American business machines manufacturer, best known originally as a typewriter manufacturer and in a later incarnation as the manufacturer of the UNIVAC line of mainframe computers but with antecedents in Remington Arms in the early nineteenth century. For a time, the...
, and IBMIBMInternational Business Machines Corporation or IBM is an American multinational technology and consulting corporation headquartered in Armonk, New York, United States. IBM manufactures and sells computer hardware and software, and it offers infrastructure, hosting and consulting services in areas...
. - Unisys History Newsletter Volume 5, Number 1
- Roger Mills' Description of the BINAC
- Picture of BINAC history sign in Northeast Philadelphia