AVR MICROCONTROLLER

In this series of tutorials we are going to cover all about avr microcontroller from basic to advance from doing any project point of view so stay tuned to my blog for updated content.
{CONTENT IS UPDATED EVERY SATURDAY}

AVR is advance virtual RISC microcontroller. So, now what is RISC.It's reduced instruction set computing.

The microcontrollers are generally either RISC based or CISC based.CISC is complex instruction set computing.Lets understand RISC and CISC by taking an example.
example of CISC is scientific calculators that we use in engineering designed to perform all the arithmetic and logical operation and also various other operation like calculating log,solution of linear equation,exp etc.
example of RISC is the buisness calculators that we generally see in any stores that are designed to perform only some specific operations that are most commonly used like +,-,*,/ etc.These are derived from the scientific calculator thats why called REDUCED.
The AVR is a RISC based microcontroller.
There's also microprocessors such as 8085,8086 microprocessors.The basic difference between the two is that microcontrollers have inbuilt RAM,ROM and others peripherals like ADC,DAC,TIMER which are on chip but in microprocessors the the peripherals are to be connected externally.

Now lets move back to AVR .It's actually an 8 bit family of microcontroller based on harvard architecture.
Now you might be thinking what's harvard architecture.So let me tell you the microcontroller are either based on HARVARD ARCHITECTURE or VON-NEUMANN MODEL.
HARVARD ARCHITECTURE-->In this architecture we have separate data and instruction buses allowing transfers to be performed simultaneously on both buses.
VON-NEUMANN MODEL-->It has only one bus which is used for both data transfer and instruction fetches and therefore data transfer and instruction fetches must be scheduled ,they cannot be performed at the same time .

Depending upon the number of pins AVR can be broadly classified into various categories:-
1.Tiny series-->It has less number of pins{8 pins}
2.Mega series{40 pins-60 pins}-->ATMEGA8,ATMEGA16,ATMEGA32,ATMEGA64
3.Classic AVR{100 pins}
4.Special purpose AVR


AT------>Atmel {Company manufacturer}
MEGA---->Mega series(40 pins)
8,16,32,64---->Flash memory also called program memory, code memory, ROM memory{8 KB,16 KB,32 KB,64 KB and so on}

Flash memory--->Its a non volatile RAM{slower than RAM but faster than hard drives}

Throughout the tutorial our main focus will be on ATMEGA16 where 16 denotes flash memory of 16kilobytes, which comes in DIP packaging{Dual In Line } packaging.
Other general forms of packaging are TQFP and LQFP.
TQFP-->Thin Quad Film/Frame Packaging.
LQFP-->Lead Quad No Frame Packaging.

The different forms of PCB generally used in engineering projects are-->
1.Single Sided PCB.
2.Double Sided PCB.
3. Multilayer PCB.
4. Flex PCB.
5.Rigid Flex PCB.