5. 1965 – Comp. Density - Double Every Year 1975 – Comp. Density - Double every 18 month
1995 – Both Ram & µprocessor follows the
Revised Law.
6.
7. The first µprocessor was developed by what was then a small company called Intel
(Integrated Electronics) in the early 1970s. The client, a Japanese company called
Busicon, declined to buy the chipset and Intel, faced with a development cost & no
customer, decided to market the chipset as a "general purpose“ µprocessing system for
use in applications where digital logic chips would have been used. The chipset was a
success and within a short while Intel developed a general purpose 4 bit
microprocessor called the 4004.
In 1974 the more powerful second generation microprocessor (the 8008) was
announced fabricated as a single chip. This was quickly followed by the Intel 8080.
Both the 8008 and the 8080 operated from a single +5v power supply (using NMOS
Technology).
At about the same time Motorola released its first microprocessor, the 6800, which was
also an 8 bit processor with about the same processing power as that of the intel 8080.
BRIEF HISTORY OF MICROPROCESSORS ¬
Steve Jobs ¬ Ted Hoff ¬
8. In the world of computers and microelectronics, much fan fare goes to the µprocessor. But there’s another important invention that
deserves some glory of its own: the microcontroller. The microcontroller is the computer chip that controls most of the complex
electronic devices people use every day, from washing machines and coffee makers to the air bags and anti-lock brakes in cars.
In 1970 and 1971, about the same time Intel was inventing its microprocessor, Gary Boone, an engineer at Texas Instruments was
working on a similar idea. At that time Texas Instruments was interested in making pocket calculators, and Boone designed a single
integrated circuit chip that held nearly all of the necessary circuits to make a calculator (except for the keypad and display). This
extraordinary breakthrough was given the rather humdrum name of the TMS1802NC, but there was nothing humdrum about the
device. Five thousand Transistor provided 3000 bits of program memory, 128 bits of random access memory, and could be
programmed to perform different functions. While Texas Instruments believed that most sales would initially go to makers of
calculators, it saw far-reaching possibilities for the new chip. With a little programming, it could be used to power electronic clocks,
scales, and various types of meters. Although the microprocessor could be the basis of a much more powerful computer, it had to
have a whole group of additional chips and circuits to make it work; at a minimum in needed memory chips, to use it with a printer,
colour monitor, sound card, or disc drive required even more chips. The microcontroller, on the other hand, was an independent
device—a computer on a chip that performed a more limited range of functions but needed only minimal help from other chips and
devices.
For that reason, the development of the microprocessor and microcontroller parted ways. Both were successful, but in terms of sheer
numbers it was the microcontroller that sold the most. Even in the late 1970s, when the personal computer was still just a gleam in the
eyes of a few guys who spent a lot of time in their garages and basements, sales of microcontrollers were rapidly accelerating. The
low-cost of the microcontroller and its all-in-one approach made it economical to develop what are now known as “embedded”
computer applications. Tiny computers could be built-in to nearly any kind of system or machine to give it added features. Some of
those applications included microwave oven, where the keypad, clock, and oven settings were monitored by a microcontroller, and
gas pumps, where metering of the gasoline and the starting of the pump were handled by the embedded computer system. Today,
microcontrollers are nearly everywhere—your home probably contains 20 or more. The latest automobiles may contain over a dozen.
By the early twenty-first century, the microcontroller was by far the top-selling chip of any kind, with well over 4 billion sold per year.
MICROCONTROLLER ¬
9. MICROCONTROLLERS ¬
The first single chip microprocessor was the 4 bit Intel 4004 released in 1971, with other more capable processors available over
the next several years. These, however all required external chips to implement a working system, raising total system cost, and
making it impossible to economically computerize appliances.
The first computer system on a chip optimized for control applications - µcontroller was the Intel 8048 released in 1976, with both
RAM and ROM on the same chip. This chip would find its way into over one billion PC keyboards, and other numerous applications.
Most microcontrollers at this time had two variants. One had an erasable EEPROM program memory, which was significantly more
expensive than the PROM variant which was only programmable once.
The Development table of µcontrollers is given as follows ¬
10. STORY OF FIRST MICROCONTROLLER ¬
It is a known fact that requirements and needs lead to inventions and discoveries.
Business at the Texas Instruments MOS Department was mostly a custom business wherein companies like desktop
calculator manufacturers came to TI with a set of specific requirements. TI converted those specifications to a chip set,
normally four, five or six chips to execute or implement the specifications for popular companies like Canon, Olympia or
Olivetti. For these companies, it was really amazing that TI provided this ultimate service of compressing so many units
on to just four or five or six chips because the previously used technology called the TTL would use hundred to two
hundred chips. No wonder the business was doing great.
It was during these times that Gary Boone was with a few other people making extensive research within the country as
well as flying to Germany, Italy and other countries. They were trying to understand the needs of the new customers and
work on it. Boone was literally bored after doing this a number of times. Besides, since their previous projects were all
successful and they had a flock of satisfied customers, a new set of customers required them to do the same work they
did to someone else the previous year. Thus, there was a significant demand for more and more of these projects.
A common rule at Texas was “one riot, one ranger” which means “one chip, one engineer.” So Texas Instruments that had
about twenty MOS design engineers deployed three or four of these at one project at a time. And, it took about six
months to complete one project. Therefore, business capacity was the number of engineers divided by the number of
chips, once in every six months. Though the requirements of these projects differed in terms of detail, the major principle
and the overall function was quite identical. So, the engineers were really tired of doing these monotonous projects. They
were working for long hours and they felt a better way to accomplish these projects should be explored.
Gary Boone ►
11. Boone and the other engineers ended up thinking of a matrix of customer needs one way and chunks of circuitry or
functional blocks the other way. Boone could find out the commonality and he, along with the others considered
simulating the thought, “Okay, now if I had these many bytes of data storage, and I had this many bytes of program
storage, and I had these many bits of keyboard scan interface, then that would cover all of the specification I know about,
maybe.” As a result of this excellent thought, came the first TMS 100 microcontroller chip. Isn’t it truly exciting to know
that this breakthrough device came out of boredom, a vision of commonalities and high demand that were being
inadequately served by deploying large teams with many chips?!
One crucial technical aspect was that the design technology in those days was quite inefficient in terms of how silicon
was utilized. Different architectures had to be chosen so that the regular structures and memory had to be emphasized;
besides, pitch-matching also had to be given emphasis so that a bit-slice concept wherein everything matching to each of
the four bits of a four bit adder was laid out to be of the same dimension in physical terms. Only then it would fit together
and match in pitch. Ultimately, another factor of three or four in terms of silicon density would be achieved.
In spite of the constraint of architectures that were primarily memory and pitch-match oriented, the then invented
µcontroller was much better than the previous TTL technology and ended up with much efficient use of silicon. This
µcontroller was used at the Texas Instruments internally in its calculator products between 1972 and 1974. The device
was further refined over the years. TI offered this µcontroller for sale to the electronics industry in 1974. It was made
available in different configurations of RAM and ROM sizes. By 1983, nearly 100 million TMS 1000 had already been
sold.
Year after year, microcontrollers were seeing tremendous growth and usage.
STORY OF FIRST MICROCONTROLLER ¬
TMS1802NC ►
12. INTEL MICROCONTROLLERS ¬
Intel also created many significant µcontrollers besides producing the world’s first ever
microprocessor. The important ones produced by Intel are the 8048 and the 8051 microcontrollers.
8048 was introduced in 1976 and was the first of Intel’s µcontroller. It was used as the processor
in the PC keyboard of IBM (International Business Machine).
The 8051 µcontroller was introduced in 1980 and is one of the most popular µcontroller. It is even
used now and is considered to be one of the most long-lived µcontroller.
13. EEPROM FLASH
ERASABLE MEMORIES ¬
It was during the 1990s that advanced µcontrollers with electrically erasable and programmable
ROM memories such as the flash memory started flooding the electronics market.
The unique feature of these µcontrollers is that they can be programmed, erased and
reprogrammed with the help of just electrical signals.
A lot of currently used µcontrollers such as the ones available from Atmel and Microchip use the
flash memory technology.
EPROM
14. MODERN MICROCONTROLLERS ¬
Today, in addition to the general purpose gadgets, unique µcontrollers are being created for areas
like lighting, automotive, communications, and low-power driven consumer goods.
The present day µcontrollers like AVR [Alf (Eigil Bogen) & Vegard (Wollan)’s Risc Processor], and
PIC (Peripheral Interface Controller) have become smaller and sleeker yet more and more
powerful. For instance, there are so tiny microcontrollers available, small and cheap enough to be
used in simple products like toothbrushes and toys.
