Four-Phase Systems was a computer company, founded by
Lee Boysel and others, which built one of the earliest computers using semiconductor main memory and
MOS
MOS or Mos may refer to:
Technology
* MOSFET (metal–oxide–semiconductor field-effect transistor), also known as the MOS transistor
* Mathematical Optimization Society
* Model output statistics, a weather-forecasting technique
* MOS (filmm ...
LSI logic. The company was incorporated in February 1969 and had moderate commercial success. It was acquired by
Motorola
Motorola, Inc. () was an American Multinational corporation, multinational telecommunications company based in Schaumburg, Illinois, United States. After having lost $4.3 billion from 2007 to 2009, the company split into two independent p ...
in 1981.
History
The idea behind Four-Phase Systems began when Boysel was designing MOS components at
Fairchild Semiconductor
Fairchild Semiconductor International, Inc. was an American semiconductor company based in San Jose, California. Founded in 1957 as a division of Fairchild Camera and Instrument, it became a pioneer in the manufacturing of transistors and of int ...
in 1967. Boysel wrote a manifesto explaining how a computer could be built from a small number of MOS chips. Fairchild made Boysel head of a MOS design group, which he used to design parts satisfying the requirements of his putative computer. After doing this, Boysel left to start Four-Phase in October 1968, initially with two other engineers from his Fairchild group as well as others. Boysel was not sued by Fairchild, perhaps because of chaos caused by a change in Fairchild management at that time. When the company was incorporated in February 1969, he was joined by other engineers from the Fairchild group.
Robert Noyce
Robert Norton Noyce (December 12, 1927 – June 3, 1990), nicknamed "the Mayor of Silicon Valley", was an American physicist and entrepreneur who co-founded Fairchild Semiconductor in 1957 and Intel Corporation in 1968. He is also credited wit ...
, co-founder of
Intel
Intel Corporation is an American multinational corporation and technology company headquartered in Santa Clara, California. It is the world's largest semiconductor chip manufacturer by revenue, and is one of the developers of the x86 seri ...
, was an early board member.
Boysel arranged for chips to be fabricated by Cartesian, a
wafer-processing company founded by another engineer from Fairchild. Four-Phase showed its system at the
Fall Joint Computer Conference The Joint Computer Conferences were a series of computer conferences in the United States held under various names between 1951 and 1987. The conferences were the venue for presentations and papers representing "cumulative work in the omputerfield ...
in 1970. By June 1971, Four-Phase IV/70 computers were in use at four different customers, and by March 1973, they had shipped 347 systems to 131 customers. The company enjoyed a substantial level of success, having revenues of $178 million by 1979.
In 1982, Four-Phase was sold to Motorola for a $253 million stock exchange. The former location of the business on N De Anza Blvd is now Apple's
Infinite Loop
In computer programming, an infinite loop (or endless loop) is a sequence of instructions that, as written, will continue endlessly, unless an external intervention occurs ("pull the plug"). It may be intentional.
Overview
This differs from:
* ...
campus.
System
The Four-Phase CPU used a
24-bit word size. It fit on a single card and was composed of three AL1 chips, three read-only-memory (ROM) chips, and three
random logic Random logic is a semiconductor circuit design technique that translates high-level logic descriptions directly into hardware features such as AND and OR gates. The name derives from the fact that few easily discernible patterns are evident in the a ...
chips. A memory card used Four-Phase's 1K RAM chips. The system also included a built-in video controller which could drive up to 32 terminals from a character buffer in main memory.
[Brochure, System IV/70, Four Phase Systems]
From the Computer History Museum. Accessed on line June 11, 2010. Also see
The AL1 was an 8-bit
bit slice
Bit slicing is a technique for constructing a Processor (computing), processor from modules of processors of smaller bit width, for the purpose of increasing the word length; in theory to make an arbitrary ''n''-bit central processing unit ( ...
which contained eight registers and an arithmetic logic unit (ALU). It was implemented using
four-phase logic
Four-phase logic is a type of, and design methodology for dynamic logic. It enabled non-specialist engineers to design quite complex ICs, using either PMOS or NMOS processes.
It uses a kind of 4-phase clock signal.
History
R. K. "Bob" Boo ...
and used over a thousand gates, with an area of 130 by 120
mils (3.3 mm by 3 mm). The chip was described in an April 1970 article in ''Computer Design'' magazine. Although the AL1 was not called a
microprocessor
A microprocessor is a computer processor where the data processing logic and control is included on a single integrated circuit, or a small number of integrated circuits. The microprocessor contains the arithmetic, logic, and control circu ...
, or used as one at the time, it was later dubbed one in connection with litigation in the 1990s, when
Texas Instruments
Texas Instruments Incorporated (TI) is an American technology company headquartered in Dallas, Texas, that designs and manufactures semiconductors and various integrated circuits, which it sells to electronics designers and manufacturers globall ...
claimed to have patented the microprocessor. In response, Lee Boysel assembled a system in which a single 8-bit AL1 was used as part of a courtroom demonstration computer system, together with ROM, RAM and an input-output device. The AL1 is considered to be the first microprocessor used in a commercial product (vs the
Intel 4004
The Intel 4004 is a 4-bit central processing unit (CPU) released by Intel Corporation in 1971. Sold for US$60, it was the first commercially produced microprocessor, and the first in a long line of Intel CPUs.
The 4004 was the first signific ...
, the first commercially available microprocessor).
References
*{{Dead link, date=December 2019 , bot=InternetArchiveBot , fix-attempted=yes
Lee Boysel – Making Your First Million And Other Tips for Aspiring Entrepreneurs
Defunct computer hardware companies
Technology companies based in the San Francisco Bay Area
1969 establishments in California
Companies based in Cupertino, California
Computers using bit-slice designs