CALDIC
Encyclopedia
CALDIC was an electronic digital computer built with the assistance of the Office of Naval Research
at the University of California, Berkeley
between 1951 and 1955 to assist and enhance research being conducted at the university with a platform for high-speed computing.
CALDIC was designed to be constructed at a low cost and simple to operate. It was a serial decimal machine with an 8 inches (203.2 mm), 10,0000-word magnetic drum memory. (As CALDIC's decimal words were 10 digits each, the magnetic memory could store about 400,000 bits.) It contained 1,300 vacuum tube
s, 1,000 crystal diodes, 100 magnetic elements (for the recording heads), and 12 relay
s (in the power supply). It was capable of speeds of 50 iterations per second. CALDIC was a stored program
computer with a 6-digit instruction format (2 digits for the opcode
and 4 digits for the memory address).
The computer was initially planned by Paul Morton
, Leland Cunningham
, and Dick Lehmer
; the latter two had been involved with the ENIAC
at the University of Pennsylvania
, and Lehmer had given one of the Moore School Lectures
. Morton oversaw the design and construction with a team comprising electrical engineering
graduate and undergraduate students at the university, more than 35 in total, including Doug Engelbart
(who later invented the computer mouse) and Al Hoagland (a pioneer of the computer disk industry).
The machine was mostly operational in 1954. Development cost through July, 1955 was approximately $150,000.
Office of Naval Research
The Office of Naval Research , headquartered in Arlington, Virginia , is the office within the United States Department of the Navy that coordinates, executes, and promotes the science and technology programs of the U.S...
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...
between 1951 and 1955 to assist and enhance research being conducted at the university with a platform for high-speed computing.
CALDIC was designed to be constructed at a low cost and simple to operate. It was a serial decimal machine with an 8 inches (203.2 mm), 10,0000-word magnetic drum memory. (As CALDIC's decimal words were 10 digits each, the magnetic memory could store about 400,000 bits.) It contained 1,300 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, 1,000 crystal diodes, 100 magnetic elements (for the recording heads), and 12 relay
Relay
A relay is an electrically operated switch. Many relays use an electromagnet to operate a switching mechanism mechanically, but other operating principles are also used. Relays are used where it is necessary to control a circuit by a low-power signal , or where several circuits must be controlled...
s (in the power supply). It was capable of speeds of 50 iterations per second. CALDIC was a stored program
Von Neumann architecture
The term Von Neumann architecture, aka the Von Neumann model, derives from a computer architecture proposal by the mathematician and early computer scientist John von Neumann and others, dated June 30, 1945, entitled First Draft of a Report on the EDVAC...
computer with a 6-digit instruction format (2 digits for the opcode
Opcode
In computer science engineering, an opcode is the portion of a machine language instruction that specifies the operation to be performed. Their specification and format are laid out in the instruction set architecture of the processor in question...
and 4 digits for the memory address).
The computer was initially planned by Paul Morton
Paul Morton
Paul Morton was a U.S. businessman.- Biography :He served as the Secretary of Navy between 1904 and 1905. Previous to this, he had been vice president of the Santa Fe Railroad...
, Leland Cunningham
Leland Cunningham
Leland Erskin Cunningham was an American astronomer. In a career spanning 50 years, he became an authority on orbit theory and on precise measurements of the orbits of comets, planets, satellites, and space probes...
, and Dick Lehmer
Derrick Henry Lehmer
Derrick Henry "Dick" Lehmer was an American mathematician who refined Édouard Lucas' work in the 1930s and devised the Lucas–Lehmer test for Mersenne primes...
; the latter two had been involved with the ENIAC
ENIAC
ENIAC was the first general-purpose electronic computer. It was a Turing-complete digital computer capable of being reprogrammed to solve a full range of computing problems....
at the University of Pennsylvania
University of Pennsylvania
The University of Pennsylvania is a private, Ivy League university located in Philadelphia, Pennsylvania, United States. Penn is the fourth-oldest institution of higher education in the United States,Penn is the fourth-oldest using the founding dates claimed by each institution...
, and Lehmer had given one of the Moore School Lectures
Moore School Lectures
Theory and Techniques for Design of Electronic Digital Computers was a course in the construction of electronic digital computers held at the University of Pennsylvania's Moore School of Electrical Engineering between July 8, 1946 and August 30, 1946, and was the first time any computer topics had...
. Morton oversaw the design and construction with a team comprising electrical engineering
Electrical engineering
Electrical engineering is a field of engineering that generally deals with the study and application of electricity, electronics and electromagnetism. The field first became an identifiable occupation in the late nineteenth century after commercialization of the electric telegraph and electrical...
graduate and undergraduate students at the university, more than 35 in total, including Doug Engelbart
Douglas Engelbart
Douglas Carl Engelbart is an American inventor, and an early computer and internet pioneer. He is best known for his work on the challenges of human-computer interaction, resulting in the invention of the computer mouse, and the development of hypertext, networked computers, and precursors to GUIs...
(who later invented the computer mouse) and Al Hoagland (a pioneer of the computer disk industry).
The machine was mostly operational in 1954. Development cost through July, 1955 was approximately $150,000.