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Part II 

1970' s - The AUair/Apple Era. 

3/2 Paitll 1970-s--TheAltair/Apple 

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Figure 3.1: R graphical history of personal compul 
the 1970' s, the MIT3 Rltair and Apple Computer 

Microprocessors in the 1970's 3/3 

Figure 3.2: Andrew 3. Grove, Robert X. [I.?yce and Gordon 


Figure 3.3: Marcian E. "Ted" Hoff. 
ographs are courtesy of Intel Corpora 

3/4 Paitll 1970's--TheAltair/Apple 

Figure 3.4: The Intel MC3-4 (Micro Computer Sys" 

y of Intel Corpoi 

Chapter 3 Microprocessors in the 1970's 

The creation of the tcansistoc in 1947 and the 
development of the integrated circuit in 1958/59, is the 
technology that formed the basis for the microprocessor. 
Initially the technology only enabled a restricted 
number of components on a single chip. However this 
changed significantly in the following years. The 
technology evolved from Small Scale Integration (SSI) in 
the early 1960's to Medium Scale Integration (MSI) with 
a few hundred components in the mid 1960's. By the late 
1960's LSI (Large Scale Integration) chips with 
thousands of components had occurred. 

This rapid increase in the number of components 
in an integrated circuit led to what became known as 
Moore's Law. The concept of this law was described by 
Gordon Moore in an article entitled "Cramming More 
Components Onto Integrated Circuits" in the April 1965 
issue of Electronics magazine [338| . Moore' s Law 
initially stated that the number of transistors on a 
semiconductor chip would keep doubling every year. This 
was later changed to every 18 to 24 months. The "law" 
has held up remarkably well since 19 65 and has had a 
profound effect on computer technology. 

Advanced chip technology enabled Texas 
Instruments to develop the first electronic calculator 
in 1967. Then they worked with the Canon company to 
produce the worlds first pocket calculator, the 
Pocketronic in April 1971. During this period another 
company called Intel had entered the semiconductor 

3.1 ... Intel 

The Beginuing 

Gordon E . Moore and Robert N . Noyce resigned from 
Fairchild Semiconductor and founded a company called N M 
Electronics that they incorporated in July 1968. Noyce 

3/6 Part II 1970's -- The Altair/Apple era 

the integrated circuit at Fairchild, Moore the director 
of the research and development laboratory. Rrthur Rock 
and other investors provided venture capital for the 
company startup. Shortly after, they changed the company 
name to Intel Corporation, signifying Integrated 
electronics. Andrew S. Grove who was assistant director 
of research and development at Fairchild joined Intel 
shortly after the founding as director of operations. 
The company became a public corporation in October 1971. 

The initial focus of the company was to develop 
large scale integrated (LSI) memory chips to replace 
magnetic core memory. Intel introduced the 1101, a 256 
bit MOS static random access memory in September 1969. 
Then Intel started producing the 1103 chip, the worlds 
first IK bit dynamic random access memory (DRRM) in 
October 1970. This provided significant reductions in 
the cost of computer memory. However a request for logic 
chips would change the focus of the company to include 

The First Microprocessor (4-Bi0 

In April 1969, a Japanese calculator company 
called Busicom asked Intel to develop a set of at least 
twelve custom logic chips for a new low cost desk top 
calculator. Marcian E. "Ted" Hoff evaluated this request 
and determined that the design configuration proposed by 
the customer was too complex. Hoff had experience with 
the DEC PDP-8 architecture and proposed that Intel 
develop a four-chip set incorporating a general-purpose 

calculator BCD (Binary Coded Decimal] requirements and 
possibly other applications. Intel's executive staff 
approved the proposal and design proceeded with 

the Intel proposal for a general processor and 
associated chips in October 1969. 

Busicom paid Intel 560,000 to produce the chip 
family configuration for use in their calculators in 
early 1970. Federico Faggin who joined Intel in April 
1970, did the detailed circuit design and layout of the 
chips. The final configuration consisted of four 16 pin 

Microprocessors in the 1970's 3/7 

(CPU) , a 256 by 8-bit read only memory (ROM) , a 320-bit 
random access memory (RAM) and a shift register for 
input/output (l/O) . The CPU chip measured one-eighth of 
an inch wide by one-sixth of an inch long and had about 
2, 300 transistors. The CPU included a 4-bit parallel 

push-down stack on one chip. This CPU chip became known 
as the 4004 4-bit microprocessor. It had a set of forty 
five instructions, operated at 108 kilohertz and could 
execute 60,000 operations a second. Faggin produced 
working samples in nine months and Intel delivered sets 
of chips to Busicom in March 1571. 

In early 1971, Busicom got into financial 
difficulties and Intel obtained the design rights for 
applications other than calculators in return for a 
lower price on the chips. In mid-November 1971, the 
first advertisement for a commercially available 
microprocessor, the Intel 4004 appeared in Electronic 
News. Intel advertised it as the MCS-4 {Micro Computer 
System 4-bit) family of four integrated chips. The 
advertisement stated it was "Announcing a new era of 
integrated electronics... A micro-programmable computer 
on a chip!" The 4004 CPU chip sold for S200. It was 
indeed the beginning of a new era, but the 8-bit 
microprocessor is what started the microcomputer 

S-Bit Mtcropro cessors 

In late 19 69, concurrent with the Busicom 
development. Computer Terminal Corporation (GTC) , which 
later became Datapoint , contracted with Intel and Texas 

intelligent terminal. Ted Hoff and Stan Mazor analyzed 

integrated chip could contain all the logic. Intel 
initially assigned the chip design to Hal Feeney. Then 
at the end of 1970 Federico Faggin directed the 
development of the chip that became the Intel 1201. 
During the summer of 1971 Datapoint agreed to let Intel 
use this architecture in exchange for a release from the 
development charges . Experience with the Intel 4004 

3/8 Part II 1970's -- The Altair/Apple era 

1201 chip to 8008 . 

Intel introduced the first 8-bit 8008 

microprocessor in April 1972 as a family of products, 
the MCS-8 (Micro Computer System 8-Bit) . The 16 pin 8008 
had 3,500 transistors and operated at about 0.2 MHz. The 
microprocessor had a set of 66 instructions, with 4 5 

six 8-bit general registers and could address 16K bytes 
of memory. The chip implemented interrupts, however the 
interrupts worked poorly. This chip with its 8-bit 

processing as compared to the 4004 4-bit microprocessor. 
It was the first true general purpose microprocessor. 

microcomputer industry. The e 

as the French Micral in 1973 

8 in 1974 used the Intel 8008 microprocessor. 

The 4004 and the 8008 chips had started the 
technology, but a new chip, the 8080 had a more 
significant impact on the microcomputer market. Federico 
Faggin proposed the new faster chip and its use of high- 
performance NM03 (H-channel Metal Oxide Semiconductor) 
technology as compared to PMOS (P-channel Metal Oxide 
Semiconductor) used on the 4004 and 8008 

microprocessors. Masatoshi Shima who had moved from 
Busicom headed the design team. Intel approved 
development in the summer of 1972 and introduced the 8- 
bit 8080 chip in April 1974. 

This new 40 pin chip with 5, 000 transistors, 
operated at 2-3 MHz, could execute 290,000 operations a 
second, had 111 instructions and could address 64K bytes 
of memory. The chip offered a tenfold increase in 
throughput compared to the 8008. It also required only 6 
support chips for operation as compared to 20 for the 
8008. Intel had an initial price of 5360 for the chip in 

MITS used this chip on the Rltair 8800 in 1975. 
The microprocessor had a significant impact on the early 
development of microcomputers. However Motorola and 

Microprocessors in the 1970's 3/9 

The Motorola MC6800 had a single +5-volt powe i: supply 
requirement and the Zilog Z-80 was faster with more 

The competitive pressure from Motorola and Zilog 
resulted in the release of a faster 8-bit 

microprocessor, the 8085 in November 1576. It had more 
functions integrated, a 113 instruction set and only 
required a single 5-volt power supply. 

The 8085 was faster but National Semiconductor 

in 1974. Intel had started a 16-bit microprocessor 
project but was having problems that resulted in a 
conservative development schedule. 

1 6-Bit Microprocessors 

Management had approved development of a unique 
16-bit architecture in late 1974 . Then in mid 1975, 
William W. Lattin who had been the manager of memory and 
microprocessor products at Motorola, moved to Intel and 

multiprocessing architecture that became the 32-bit iRPX 
432 (Intel Advanced Processor architecture) product. 
However due to product development delays and 
competitive pressures, Intel released the 8-bit 8085 in 
1976 and began a second 16-bit project that became the 

Development of the 8086 microprocessor with a 16- 
bit architecture started in 1976. Jean Claude Cornet was 
assigned to manage the project and William B . Pohlman 
who had managed the 8085 design was also the leader for 
the 8086 design team. Stephen P. Morse defined the 
microprocessor architecture and created it as an 
extension of the 8080 architecture to provide software 
compatibility, Intel introduced the 8086 with ten times 
the performance of the 8080 in June 1978. 

The chip has 29,000 transistors with a minimum 
feature size of 3 microns and at a clock speed of 5 MHz 
it has a rating of 0.33 MIPS (million instructions per 
second) . The instruction set is an expanded version of 
the 8080 with 133 instructions. Memory addressability is 

3/10 Part II 1970's -- The Altaii/Apple era 

frequencies of 5, 8 and 10 MHz. The price at launch was 

Intel introduced the 8088 microprocessor in June 
1979. It has a 16-bit internal architecture with an 8- 
bit external data bus. This 8-bit external data bus 
allowed for a simpler interfacing to the rest of the 

characteristics is similar to the 8086. The memory 
addressability is 1 megabyte and the microprocessor is 
available at clock frequencies of 5 and 8 MHz. 

IBM selected this microprocessor for the PC 
computer announced in Rugust 1981. This computer became 
a dominant product in the personal computer marketplace 
of the early 1980' s, and was crucial in helping to 

fln IEEE Micro article entitled "A History of 
Microprocessor Development at Intel" [342] and s^n Intel 
publication entitled "R Revolution in Progress: A 
History of Intel to Date" [48] provide additional 
details on Intel microprocessors and a history of the 
company. Intel had pioneered the introduction of 
microprocessors. However other companies had entered the 
marketplace with competing products. One of the other 
dominant companies was Motorola. 

3.2 ... Motorola 

Paul V. Galvin founded the Galvin Manufacturing 
Corporation in Chicago, in 1928. Then the company name 
changed to Motorola, Inc., in 1947. Following the name 
change and the invention of the transistor in 1947, the 
company opened a research laboratory in 1950, in 
Phoenix, Arizona to explore solid-state electronics. 
Motorola is now a major supplier of discreet 

Motorola introduced the 8-bit MC6800 MPU (Micro 
Processor Unit) in mid-1974. Principals in the design of 
the microprocessor and peripheral chips were Charles 
Melear and Chuck Peddle. The MC6800 used six-micron NMOS 

technology, contained 4,000 transistors and was the 















Microprocessors in the 1970's 3/11 

first microprocessor to require a single 5-volts power 
supply. This simplification of the power supply 
requirements and the related Motorola family of chips 
lowered product costs. Some early microcomputers using 
this chip were the MIT3 Rltair 680B, Sphere and SwTPC 

luced the MC680i in 1978, as "the 
35, 00-transistor single-chip 

licrocomputer system had ROM/ E PROM, 
ock and CPU. The MC6809 was a 
microprocessor with an 8-bit external bus that processed 
data internally in 16-bit words. Motorola announced the 
microprocessor in 1978. ftpple Computer selected this 
chip for the initial Macintosh computer design in 1979. 

The MC68000 was the first of the MC68000 family 
of 16/32-bit microprocessors. Principals in the design 
were Tom Gunter and Gene Schriber. The MC68000 has 61 
instructions and a capability of two million 
instructions per second (MIPS). The chip had 68,000 
transistors. It can address 16 megabytes directly and 64 
megabytes through functional segmentation. It has a 16- 
bit data bus that processed data internally in 32-bit 
words. Motorola introduced the MC68000 in 1979. Motorola 


This microprocessor had a significant impact in 
the marketplace. Rpple Computer selected the MC68000 for 
the Lisa computer, with the processor operating at 5 


la and Intel 


two dominant desigr 



3 of micropr< 


; for microcomputers 



However the 


company that playec 



role in 


introduction of 

3/12 Pai1 II 1970's -- The Altau/Apple era 
3.3 ... Texas Instruments 

J. Clarence Karcher and Eugene McDermott founded 
Geophysical Service as a partnership in May 1930. The 
company name changed to Coronado Corporation, with 
Geophysical Service, Inc., (GSI) as a subsidiary in 
January 1939. Cecil H. Green, J. Erik Jonsson, Eugene 
McDermott, H. B. Peacock and others purchased the GSI 
subsidiary in 1941. The Coronado Corporation dissolved 
in 1545 and GSI's narae changed to Texas Instruments, 
Inc. , in 1951 . 

Texas Instruments (TI) obtained a license for the 
manufacture of transistors in May 1952 and aggressively 
expanded its semiconductor business during the 1950's. 
Jack St. Claire Kilby of TI co-developed the integrated 
circuit in 1958. During the 1960's TI was a significant 
supplier of chips for consumer products such as 
calculators, watches and toys. 

Computer Terminal Corporation (CTC) , which later 

Intel) to evaluate a set of chips for a new intelligent 
terminal in late 19 69 . This requirement resulted in TI 

developing and submitting a single-chip microprocessor 
to CTC. 

TI has stated in company literature that it 

company applied for a patent in 1971 with the invention 
being credited to Gary W. Boone an Michael Cochran (the 
patent was approved in February 1978). The company 
described their invention as a "microcomputer --the 

complete computer on a single chip of silicon" [178]. TI 
advertised the integrated circuit developed for the 

caption "GPU on a chip" in June 1971. This was the first 

functional problems with the chip and never marketed it. 
However, it did lead to the subsequent development of 
the TMSIOOO microprocessor. 

TI released the TMSIOOO 4-bit microprocessor in 
1974. The chip had a set of 43 instructions and included 

a 2 

56-bit RAM foi: 



gram storage. 



edded applicat: 



16-bit micropr 



TI 9980 in the 

■ 1, 


ernal bus but 



the TI-99/4 mi 



^computer was 


Texas Instru 


rocomputer ma 



lications. Texa 

3 : 

Microprocessors in the 1970's 3/13 

:a storage and an 8,192-tait ROM for 
chip was used mainly in low-cost 
;. TI announced the TMS9000 series 
ssors in the spring of 1976, then 
te 1970's. The TI 9980 had an 8-bit 
acessed data internally in 16-bit 
nts used the TMS9900 microprocessor 
computer released in 1979. However 
successful and TI discontinued it 

lents failed to penetrate the 
t and concentrated in other 
nstruments is a leading supplier of 

3.4... Other Companies 

R number of other compan 



>rocessors in the 1970's. However 



:ed products that had a significant 

imp a 

ct on 

computer market. Those two compar 



>logy and Zilog. 

MOS Technology 

In July 1975, MOS Technology, Inc., started 

compatible with the Motorola MC6800 and would cost only 
$20. Chuck Peddle who had left Motorola and joined MOS 
Technology was a principal in the design of the 
microprocessor. Motorola subsequently forced the company 
to withdraw the 6501 because of technology 

However MOS was also developing another chip, the 
8-bit 6502 with additional features that would only cost 
$25. The chip had approximately 9,000 transistors. This 
pricing had a significant effect on the lowering of 
prices for microprocessors at both Intel and Motorola. 
This reduction in the cost of microprocessors resulted 

3/14 Part II 1970's -- The Altaii/Apple era 

the WE3C0N show in September 1975. 

The MOS 6502 miccoprocessoi: had a significant 
impact on the early miccocomputer market. The Apple II, 
Atari 400 and 800 and Commodote PET microcomputets used 
the chip. Commode te International purchased MOS 
Technology in October 1976. 

Zilog Inc. 

In the summei: of 1974, Federico Faggin and Ralph 
Ungermann decided to leave Intel and founded Zilog Inc., 
in November. Zilog is an acronym for the "last word (Z j 
in integrated (i) logic (log)." Shortly after the 
founding, the powerful oil corporation Exxon, invested 
$1.5 million in Zilog for a 51 percent controlling 
interest in the company. Faggin and Ungermann developed 
ideas for a new microprocessor and family of components 
that would be compatible and more powerful than the 
Intel 8080. Assisting in the design effort was Masatoshi 
Shima who had also left Intel and joined Zilog. It would 

instructions than the 8080. 

Zilog announced the S-80 microprocessor in 1975 
and it became available in February 1976. It operated at 
2.5 MHz, could address 64K bytes of memory and 
incorporated the 8 080 's instruction set within 158 
instructions. The chip had 8,500 transistors and was 
manufactured by the Mostek company. The Z-80 with a low 
price of $200, became a successful alternative to the 
Intel 8080. Zilog announced a faster 4 MHz version of 
the chip, the Z-80A in February 1977. A number of early 
microcomputers such as the Radio Shack TRS-80 used the 

The Z-8000 was a 16-bit microprocessor with 
17, 5 00 transistors and 110 instructions. The memory 
address capability was 48 megabytes in six segments of 
eight megabytes and the operating speed was 2.5 to 3.9 
MHz. Zilog priced the microprocessor at $195 for small 
quantities and announced it in early 1979. The 
instruction set was not compatible with the Z-80 and 
other design problems prevented it from becoming 

lithe 1970's 3/15 

Other Sources 

n number of other companies became second sources 
for the major suppliers. The following are some of the 
more significant suppliers. 

Walter Jeremiah (Jerry) Sanders was a principal 
in the founding of Advanced Micro Devices (RMD) , Inc., 
with seven other Fairchild personnel in mid 19 65. 
Sanders had worked for Motorola then Fairchild 
Semiconductor where he became sales and marketing 

source for other manufacturers chips by creating an 
equivalent design or by obtaining a license agreement 
from the other company. Early license agreements were 
with Intel for the 8085 microprocessor and with Zilog 
for the Z-8000. RMD became a public company in September 
1972 and the Siemans AG company made an investment of 
$30 million for nearly 20 percent of AMD in late 1977. 

Hewlett-Packard developed a proprietary 

was used in the company's HP-85 personal computer 
released in 1980. 

Mostek was founded by L. J. Sevin and 
subsequently became a subsidiary of United Technologies. 
It was a major supplier of semiconductor memory chips 
and a second source for other company's microprocessors 
such as the Zilog Z-80. 

National Semiconductor Corporation was founded in 
1959. Charles E. Sporck who had been at Fairchild 
Semiconductor joined the company in 1968, became the 
president and a significant contributor to the success 
of the company. The company offered microprocessor 
systems on a 8.5 by 11-inch PC card. The IMP-8 was an 8- 
bit microprocessor system and the IMP-16 was a 16-bit 
microprocessor system available in 1973. Then National 
Semiconductor announced the first 16-bit single chip 
microprocessor, called the Pace in 1974. A faster 
microprocessor called the Super-Pace followed. The SC/MP 

RCA introduced the 1802, the first complementary 
metal oxide semiconductor (CMOS) 8-bit microprocessor in 
1974, that was followed by the 1804 microprocessor. 

3/16 Part II 1970's -- The Altaii/Apple era 

Rockwell introduced the PPS-4 that was a 4-bit 
parallel processor in late 1972. It had a 50 instruction 
set. Rockwell subsequently released the PPS-8, 

Signet ics Corporation was founded by four 
Fairchild Semiconductor executives in 1961. The company 
name is an acronym for "Signal Network Electronics . " The 
company shipped an 8-bit Programmable Integrated 
Processor (PIP) in 1974 that had more than 64 
instructions. The Signetics 2650, is another processor 
available from the company around 1978. Signetics was 
also a second source for microprocessors to companies 


. Miscellaneous 
It Controversy 

During the I960' s 








uit technology contin 




rove the 



of i 

ntegrating a larger ni 

imber of 


'cuit elei 

nents. This 


ved to consideration 



le : 

in the i 




ibly creating a central 



or unit 

(CPU) o 


le chip. However the 




of cred 

it for 



ntion of the micropi 




Id the a 




nts for it have been 




ial. Companies s 


Hyatt are principals in the controversy. 

Recording to Gilbert Hyatt he built his first 
breadboard concept of a small computer in 1968, 
trademarked the term "microcomputer" and started a 
company called Micro Computer Inc (MCI) . Hyatt made 
application for a broad patent with a title "Data 
Processing System" in 1569. The application was rejected 
by the U.S. Patent Office. This was appealed by Hyatt 
and in December 1970 the Patent Office accepted a new 
application with a title "Factored Data Processing 
System for Dedicated applications . " Hyatt continued 
working on printed circuit prototypes but did not 
demonstrate or prove that his concept was practical. In 
question was Hyatt's ability to implement the patent on 
a single chip at the time of the patent application. At 
that time the technological capabilities were just 

Microprocessors in the 1970's 3/17 

single integrated chip. In September 1971, Hyatt's Micro 
Computer company went out of business. Hyatt continued 
to have problems with his patent application that 
resulted in further appeals and changes to the 

application. Then in July 1950, the U.S. Patent Office 
awarded Hyatt a patent that now had a title of "Single 
Chip Integrated Circuit Computer Architecture . " This 
immediately created significant controversy in the 
industry. However in June 1996, the patent was 

Between 1969 and March 1971, Intel conceived and 
developed the 4004 microprocessor as described in 

extended existing technology. This rather casual 
approach resulted in Intel not filing a patent 
application for the microprocessor. Ted Hoff has stated 
that he published an article in March 1970 describing 
the feasibility of building a central processor on a 
chip. This in essence placed the concept of a 

a viable patent application. 

single-chip microprocessor in 1970 as described in 
Section 3.3. However TI withdrew their microprocessor 
due to functional problems and the following products 
were not accepted by any major microcomputer 

The Texas Instrument patent that was approved by 
the U.S. Patent Office in 1978 has not been successfully 
contested. However Hyatt's patent that was approved by 
the U.S. Patent Office in July 1990 was overturned in 
1956. Neither of these patents has affected Intel which 
became the dominant supplier of microprocessors for 
personal computers . 

Rn article in Byte magazine "Micro, Micro : Who 

interviews of Hyatt, Hoff and Faggin [328] . Some 
additional comments by Federico Faggin are in another 

3/18 Part II 1970's -- The Altaii/Apple . 

[331] and in a Popular Science 

R further- article in Byte magazine entitlei 
"Evolution of the Microprocessor" provides an informa 
history [333] . The IEEE Micro article entitled "i 
History of Microprocessor Development at Intel" provide: 
some details of developments at other companies [342] 
The Encyclopedia of Microcomputers , "Architecture o 
Microprocessors," Vol. 1, pages 269-282 [236] contain: 
an extensive bibliography. 


different i 



For i 


ice Syne 



Rockwell Ir 


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>ors des: 


;d by 

MOS Technc 

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