Atmega16 is an 8-bit controller based on AVR advanced RISC (Reduced Instruction Set Computing) architecture. It is a 40-pin low power microcontroller which is developed using CMOS technology.
It is a single chip computer that comes with CPU, ROM, RAM, EEPROM, Timers, Counters, ADC and four 8-bit ports called PORTA, PORTB, PORTC, PORTD where each port consists of 8 I/O pins.
Atmega16 has built-in registers that are used to make a connection between CPU and external peripherals devices