|
|
Silicon Rabbits
Flexibility as a characteristic
in their case showed out to be warmly welcomed. We can find them
all around from toys to the most complex uses in industry
Starting from the example of a
transmitter, the traditional analog technology with its signal
of 4-20mA started to give in the place to intelligent
transmitters. We must ask ourselves, should we allow ourselves
the luxury not to get know them better? Simply said, from day to
day the instrumentation in industry works more and more under
one of the next protocols Field, Smart or Profy bus, and slowly
leaving the mentioned 4-20mA above. This way the distributivity
of the system is achieved.
Lately, it finds a very important
application in automobile industry. From 1995 'immobilizers' are
installed in cars. 'Immobilizer' is a microcontrolling system,
that controls almost everything: the proportion of air and fuel,
engine starting, ABS-breaking system, navigation,
air-conditioning, etc. It may sound silly if we tell a car
mechanic that in a year or two he will have to know a great deal
of electronics, in order to fix the car, but it is so obvious.
Those who will start out among the first, and fetch the
necessary equipment and instrumentation, will definitely gain
the largest part of the profit. Besides, those who poses a
foreign car produced after 1996 probably know what I am talking
about.
Can you remember those ugly and
old washing machine programmers? The only thing left is-to
remember them, because they all were replaced by microcontroller.
Of much smaller dimensions, much more efficient, much more
cheaper, actually 3 to 4 times cheaper then the old mechanical
ones. Using the microcontroller, we shall increase the number of
operations of our washing machine and also its intelligence.
The use in the so called ''error
memories'' allows to have evidence of improper work of devices.
Later these information are used by qualified services to track
down these improperties. This obviously is a great help for
qualified personnel.
Cameras, photo cameras, phones,
pagers, ID cards, industry control, automation, home devices,
military technology, medicine and much others use larger and
larger quantities of microcontrollers. Why should they not?
Small, fast, efficient, reliable, they easily find their use.
Above all, if we add the extremely small price, then it is
totally clear why microcontrollers achieved such a great
popularity. New working places were opened by the development of
microcontrollers. We only have to wait and see who will get these
working places...
Which
microcotroller to choose?
The answer to this question is
not so difficult, in case you exactly know what you need, and
what for is your device intended to be used. In the beginning of
microcontrollers era, there were two major microcontroller
producers dominant on the market - Intel and Motorola. By
circumstances, in our country Intel became more popular, being
more accessible on the market, on one side. On the other side,
good cooperation of Intel and our Universities and then Intel's
development tools given to the Universities, made them base
their work on Intel's environment. I must admit that the price
of Intel's microcontrollers (that always were cheaper then
Motorola's) also influenced this situation. A slight passivity
of Motorola on non-USA markets and the orientation to bigger
systems, just influenced the increase of the number of Intel's
users on our grounds. This number increased more and more when
Intel started to give the license of the microcontrollers based
on 80C31 to other companies. Companies like Dallas Semiconductor
and Siemens, increased the chips performances and on
the other side kept the vertical compatibility with 80C31.
This situation on the market
would possibly last till today. But the fact is new companies
appeared and started the production of microcontrollers.
Microchip
The first one among those who
noticed the chance to enter the market was Microchip from USA,
Arizona. Their start still fascinates me. But actually no matter
we discuss microcontrollers or other products, this strategy
should generally be used. They simply noticed a gap on the
market. Calculated the pros and cons, took a risk and like a
thunder they placed themselves on the market with their product.
Microchip offered something completely new. A microcontroller
with a simple architecture, reduced instruction set (RISC) and
minimal power dissipation. Although Microchip is for a short
time on the market, their PIC microcontrollers gained a large
number of users. Thanks to a pretty aggressive marketing
campaign and good technical support, the number of their users
increases day by day. The low price also was one of the most
important factors. Especially the OTP version is mostly used. We
will all always remember the fact that Microchip
introduced the first 8 pin microcontroller to us. One year ago,
when I read this news, I doubted the usability of such a small
microcontrollers. Now it's different, considering that it
possesses an internal oscillator. And the latest model possesses
an AD converter. Besides, in our magazine we will show a few
interesting projects using this microcontroller.
Atmel
I guess if the owners of
Microchip were able to control the microcontroller market, they
would have probably left the things on that level. Once again
the old rule showed it is easier to gain success then to
preserve it. At the same time with the appearance of Microchip
on the market, another company started to prepare a strategy for
microcontrollers market assault. The name of this company, Atmel.
Also from the USA. Their story is a little bit different, and
less risky from my point of view, then Microchip's. They first
designed a microcontroller based upon Intel's 80C31 but they
implanted a flash memory of bigger capacity, that was easy to
reprogram. This way the progress based on these microcontrollers
was more simplified. With this move, a large number of new users
was guaranteed. But actually with less profit, because there
were also other producers that offered same kind of products,
including Intel. Intel offered his 80C31 microcontroller for only
2-3 Deutsche Marks per sample. The first important step towards
what Atmel represents today was made when Atmel introduced the
AT89C1051 microcontroller. And later AT89C2051, that differs from
the previous only by the size of internal flash memory
(1 & 2Kb, and now they have versions with 4Kb). The idea was
simple. If a microcontroller has a memory inside it, then it
simply does not need any address and data lines. This move
reduced the size of housing to 20 pins DIP, and also reduced the
necessary space on the circuit boards. Now the programmers that
worked and developed their libraries for 80C31 during years of
time, had a small and flexible microcontroller at hand to use.
And of course without a need to learn a new programming
language. Most possibly the profit of this project influenced
Atmel to involve more seriously in the market of microcontrollers.
The next step amazed me as much as the appearance of Microchip's
PIC microcontroller that year before. Atmel decided to develop a
completely new microcontroller also in RISC technology, but with
a little more expanded set of instructions, and with such a
choice of models of microcontrollers that directly attacked
almost all the companies on the market. Atmel's new family's
name is AVR and is signed AT90S...so briefly, there is AT90S1200
with 1Kb of flesh memory in 20 pin DIP housing, then AT90S8515
with SPI, SCI communication, 8Kb flesh memory, packed in DIP40
or PLCC44 and ATmega103 with 128Kb of flesh memory, 4Kb eeprom
4Kb RAM, 10 bit AD converter SPI, SCI communication and 64
TQFP package. A short time ago we received the first specimen,
and I only can describe it as 'amazing'. The thickness of the
chip is almost equal to the thickness of a bigger confetti.
Recently there was presented an 8 pin microcontroller,
similar to Microchip's family 12CXXX. We will try to
present this microcontroller in details to you, in one of our
next issues.
Software Support
The choice of a software support
is of great importance, when selecting a microcontroller to use.
This is a very important issue, because the price of the
software tools can be pretty high, and in most of the cases
determines the choice of the microcontroller to use. Atmel has
done a great step, giving an excellent assembler and simulator
for Widows platforms for their AVR microcontrollers for no
charge. Motorola has its PCbug, the old good ASM11
assembler and above all C programming language for public use.
Microchip also gave assemblers and simulators for no charge, but
Atmel's C is very rare. Intel is present for a long time
on the market, and probably has the largest software support.
Besides another advantage is that its assembler is almost
identical to the one used for programming PC computers.
Generally speaking, the assembler is very well supported by all
the companies, and it is what we usually start with.
The others?
Besides the producers mentioned
above, there are other companies present like SGS Thompson or
Hitachi. Only these companies are not as present on our market.
This is the reason why they won't be mentioned in details this
time.
During my writing of this
article, I tried not to suggest you any of the microcontrollers
and especially not to advise you which one is better then the
other. I think the right solution is to find the microcontroller
that fits your needs the best. The real solution will be to try
to find out the information about the families that interest you
by yourself. Judging the parameters like architecture, price,
software support, availability on the market and others, you
will make the best choice for you. I hope we managed to help you
make a right choice using the information given in our
magazines, in each issue.
Someone may think that from the
written above we may conclude that Motorola and Intel are
loosing the race with Atmel and Microchip. That Atmel pushes
Microchip, and that the good old 80C31 is dead. We must not
simplify the things so easily. Motorola and Intel have a long
tradition in 16 and 32 bit microcontrollers in comparison to
Atmel and Microchip. Intel has a large number of users, and this
should not be underestimated. Then Motorola has its standardly
good architecture with good old BOOT mod, whose simplicity can
not easily be copied by others. Atmel on the other side goes
aggressively, with low prices of its AVR family, but is only at
the start, and at this moment has a small number of users on our
market. Intel, thanks to his licenses, is still active on the
market and probably will be for a long time.
And what happens in the end?
In case you carefully listed
(read) this issue, you should have not missed the article about
the entire PC in a single chip. How will this affect the microcontroller's world, it is to be seen in the future. Probably
the designers of some more demanding applications will welcome
the coming of this chip. Then probably to others this will not
be interesting till the prices drop to the level of nowadays microcontrollers prices. In any case the appearing of this chip
is quite fascinating. We already contacted the manufactures and
we expect a testing specimen pretty soon. We will gladly
inform you about it as soon as we receive it and test it.
If you deal with microcontrollers
or anything connected to them, one thing is certain. You must be
happy! There is a large range of microcontrollers on the market.
A choice we always desired to have...
author: Nebojša
Matić
translated by: Simeon
Todoran
|
