# Detail of AVR microcontroller

AVR stands for Alf Vegard RISC which is a microcontroller designed by Atmel and now owned by Microchip. The AVR was one of the first microcontrollers families to use on-chip flash memory for program storage, as opposed to OTP ROM, EPROM or EEPROM used by other microcontrollers at that time.

# Classification

AVR microcontroller are generally classified as tinyAVR, megaAVR, XMEGA.

  1. TinyAVR: The ATtiny series consists of :

    • 0.5–16 kB program memory
    • 6–32-pin package
    • Limited peripheral set
  2. MegaAVR:The ATmega series consists of :

    • 4–512 kB program memory
    • 28–100-pin package
    • Extended instruction set (multiply instructions and instructions for handling larger program memories)
    • Extensive peripheral set
  3. Xmega:The ATxmega series consists of :

    • 16–384 kB program memory
    • 44–64–100-pin package (A4, A3, A1)
    • Extended performance features, such as DMA, “Event System”, and cryptography support.
    • Extensive peripheral set with ADCs

# Features of AVR Microcontroller atmega32

  1. Memory

    • Program Memory : 32K bytes of In-System Programmable Flash memory , it is also called program memory as it store the program flashed to micro controller .

    • ROM : It consists of 1k bytes Electrically Erasable Programmable Read Only Memory (EEPROM) . This is the type of non-Volatile memory integrated into the microprocessor , micro-controller in order to store the limited amount of data.

    • Data Memory : It consists of 2K byte SRAM , It is also called data memory as the data are stored on it during the program execution.

  2. Clock The clock generation module supports various clock sources

    • Internal Clock Sources : The device is shift with 1Mhz internal clock and it extends up-to 8 Mhz
    • External Clock Sources : Microcontroller can be clocked upto 16 Mhz externally.
  3. Interrupts

    • Internal and External Interrupts
  4. Programmable Pins

    • 32 general purpose I/O lines
  5. Counter/Timer

    • 3 flexible Timer/Counters with compare modes
  6. ADC

    • 8-channel, 10-bit ADC
  7. Communication Protocol Supported

    • Serial programmable USART
    • Byte oriented Two-wire Serial Interface ( I2C )
    • SPI serial port