What is a Microcontroller in Electronics? Key Features and Common Applications

what is microcontroller ?

http://bit.ly/XnnaQ0

I don't think there's any strict definition and as processors become more powerful the distinctions change. Originally a microprocressor was a 4 or 8 bit processor with external ram and rom or prom but few other external components. The first I used extensively were in racks of cards with separate cards for 1 bit ram and rom chips. They were 4 or 8 bit processors. Now they commonly include the ram and prom and may have 16 bit processors. As processors become more powerful and more functions are integrated into the processor the distinctions are becoming blured. I don't know whether some of the highly integrated powerful processors in portable devices would be called microprocessors.

A little-bitty, teeny-tiny, ittsi-bitsi, little-bitty controller.

--Thank you Gilda Radner (1946-1989)

But seriously, the distinction between a uController and a Microprocessor is in a uController everything is self contained within one package. A Microprocessor is merely the processing component to a larger system composed of such things as RAM, program memory, peripheral devices such as UART, Data Buffer, parallel port(s), and any number of real-world interfaces.

A uController contains all of that in one package, including the following typical components:
* PWM/Capture/Compare
* ADC
* Timers/RTCC/Watchdog
* Serial interface (such as UART/USART/SPI/I²C)
* EEPROM
* etc.

This is a good general rule but they problem comes with "typical". I know of counter examples to this, especially historically, so it can be only a marketing distinction.

http://en.wikipedia.org/wiki/Microcontroller
. . . will tell you everything you need to know (well almost).

You wil find Wikipedia very useful as a initial source of technical information.

Good information.

It is like. Recording device. You record information into IC. To make it work as you want.
I like pic-micro controller it easy to use for example 16F84 (old IC)

To classify it as a "Recording Device" is misleading. They generally _do_ have the ability to record _information_, but that can be view two ways.
# You can, likely, program a uController to do a _data logging_ type operation, or even a record sound or the like (if there is sufficient internal memory).
# You can store code that manipulates the uController - but that is rarely referred to as _recording_ [standard terms: _burn_, _write_, _program_, even _upload_].

I looked on Wikipedia:

"A microcontroller (sometimes abbreviated µC, uC or MCU) is a small computer on a single integrated circuit containing a processor core, memory, and programmable input/output peripherals. Program memory in the form of NOR flash or OTP ROM is also often included on chip, as well as a typically small amount of RAM. Microcontrollers are designed for embedded applications, in contrast to the microprocessors used in personal computers or other general purpose applications."

They do say Program memory ... is also often included ... as well as a typically small amounts of RAM. They seem to indicate the distinction is the application, whether it's embedded v.s. personal computers or general purpose.

That distinction is getting vague. Is the controller in a phone that's capable of running applications (programs) a microprocessor or a microcontroller? How about a small system that uses the cloud for computing?

Most microprocessors have both internal rom for such things as a boot loader and ram for registers such as the program counter, though I realize that is putting too fine a point on it.

I think the distinction can be determined with the following test:

Can the device store a program and by following it, do meaningful work on it's own?

A µProcessor has no way to store a program on it's own that it can execute by it's self. A µController can. In other words, a µProcessor requires supporting components to function, whereas a µController doesn't.

Or is that an archaic point of view?

Hi

1. What is a browser?
2. What is a server?
3. What is a client?
4. What is a uniform recourse locator?
5. How do I use a search engine
6. What’s a switch
7. What’s is meant by logic one and logic zero
8. What is a register
9. What is an instruction counter
10. What is memory
11. What is a micro processor?
12: Addressing Offset Addressing
13: Bits , Bytes , nibbles
14: Boolean Logic predicate calculus
15: binary adders , half adders, mux demux
16: Protocols Packets , ports , TCPIP
17: Object metholidgy
18: High level langauges
19: Assembler , number bases, more maths , octal , binary , hexidecamal
20: IO Streams
21: Tables ; how to implement
22: Computer systems organisation
23: Million instructions per second MIPS
24: under number notation How do we represent numbers in on a PC integers , long numbers , floating point numbers
25: IEEE Standards



Now we getting there !!

First Learn the basics

maybe even start with some of the basic langauge to illustrate


Answer for immediate questions after learning what the internet is, what a browser is for, what is meant by HTML and what does this do

Next step is learn what a micro does after you’ve leant how to seek out the information you need



www.parallax.com/dl/docs/books/edu/wamv2_2.pdf
or
en.wikipedia.org/wiki/Microcontroller
or
http://www.futureelectronics.com/en/Microcontrollers/microcontrollers.aspx
or
electronics.howstuffworks.com/microcontroller1.htm
or
electronics.howstuffworks.com/microcontroller.htm
or
www.webopedia.com/TERM/M/microcontroller.html
or
www.technologystudent.com/pics/picgen1.html
or
www.societyofrobots.com/microcontroller_tutorial.shtml

Followed by THE FETCH, DECODE, EXECUTE CYCLE OF A MICRO giving you the basics of how a micro , cpu works

http://www.teach-ict.com/gcse_computing/ocr/212_computing_hardware/cpu/miniweb/pg3.htm#

Having understood this you then move onto
BIOS (basic input/output system)

http://whatis.techtarget.com/definition/BIOS-basic-input-output-system

A microcontroller is a one-chip computer that runs it code from flash memory, or some other read-only memory.

From your TV remote control to a mobile ringtone. Microcontroller is everywhere. It is nothing but an electronic circuit.

Microcontrollers are basically one type of IC od integrated Circuit. It is structured by basic logic gates in one complex design. What it does is to take one or more inputs and controls the operation according to the instructions. It's range if essentially from 7 to 40 pins.

Source: Electrodiction

A microcontroller doesn't require input(s). It can function just fine without them, It depends on the application.

TO put it another way: A microcontroller doesn't require inputs. An application might, but a microcontroller, itself, doesn't need them.

Basically it consists of (CPU , MEMORY and I/O peripherals) so you can consider it as a small computer with less complexity and calculations power than that in a normal computer. Usually you write a program to do a specific task and burn it into the microcontroller memory. Then the microcontroller execute this program.