AVR ATMega8535 is a very popular microcontroller.
In the recent years, ATMega8535 has been displaced by the other microcontroller with a more complete feature like ATMega32, ATMega16 or ATMega128. Even, when Arduino offers ease (in the used and programming), the conventional Microcontroller becoming obsolete.
However, some users are still loyal to use the conventional microcontroller. And if you want to learn about the basics of the microcontroller, then you have to learn from the conventional microcontroller. You have to create an electronic circuit by yourself. And you have to find out all about the components used. After you finish creating the electronic circuits, then you will understand how the microcontroller’s minimum system so that it able works. And you will understand how a microcontroller work, before you start programming it.
Like other microcontroller, AVR ATMega8535 need some electronic components so that it able to work.
Crystal,some resistor and capacitor for the clock and the reset button. And don’t forget to provide the supply (VCC and GND) on the microcontroller board. You can make the ATMega8535 schematic diagram with the EAGLE software like the exsample above.