Starting with Microcontrollers



Categories: Microcontrollers Tags: 8051 ATmega AVR Microcontrollers

A long time after starting of blog, finally I am writing a startup article on microcontrollers. Actually like every other category, the first one is very basic and introductory in nature. The intention of this article is to introduce to microcontrollers. It goes into history of the device, it shows you the applications of the device and it shows a course to learn to operate microcontrollers.

Microcontroller is a Integrated Circuit which have a CPU, RAM, I/O Buffers, UART etc. A microcontroller is a small computer, which has inbuilt memory, input output and many other devices. It is mainly used to design embedded system, unlike to microprocessor, which is used in Personnel computers or general purpose computers.

Why do you need microcontrollers?

In this world of technology, you may find a microcontroller in almost any electronic device. Whether it be your luxury gadget or your daily need machine!! There are very high chances that it may contain a microcontroller.

At present,  there are many companies making microcontroller chips. Atmel, NXP, ST Microelectronics, Freescale, Texas Instruments are major players in this market. 8051 was first microcontroller chip. It was designed by Intel. It was a fairly simple microcontroller, as compared to today?s high end microcontrollers. Despite of being a simple microcontroller, it found application in a large variety of application.

8051 is also used as a starting point in education of Embedded System design. It has a simple architecture, which enables a novice to easily get familiar with the functioning of device. A microcontroller based system is used for designing special purpose computing system. It may be used a Timing control unit in your washing machine, or as temperature control system inside your oven etc.

A microcontroller functions by executing a set of instructions. This set of instructions is called program. A microcontroller program may be written using Assembly Language, C language or Basic language etc. But basically a microcontroller can not understand any of these languages. It can understand only binary or Hex codes. Programs written in these languages are converted into Hex code using a Assembler or a compiler. This Hex code is then transferred to the program memory of the microcontroller. The CPU present in microcontroller starts reading the instructions from memory and execute them.

Microcontrollers paved way to a small, sophisticated and state of art embedded system design. Since it contains memory(RAM, ROM, program memory etc), I/O peripherals, UART etc all inside a single chip, the emerging system is very small in size. It is unlike to a microprocessor based system, in which RAM, ROM, UART all devices need to be connected separately. A microcontroller based system consumes less power. It can be used in battery operated device, enabling them to run for long time without any external power source.

But there are some limitations associated with the use of microcontrollers. They have very limited capabilities. Their CPU speed is very less when compared to processor. They have limited amount of RAM, ROM and program memories, which limits the size of program to be fed into it.

Despite of its limitations, microcontroller have found its used in a variety of systems. It is mainly because of its low power usage and low cost which makes microcontroller based system effective.

So, there is an edge over others, in learning the art of designing systems with Microcontroller. It is not a complete article on microcontrollers. Please make it complete by providing your comments below.