At the heart of the Arduino is the microcontroller. A microcontroller is a standalone, single-chip integrated circuit that contains a CPU, read-only memory, random access memory and various I/O busses. Most Arduino boards use the Atmel 8-bit AVR microcontroller.
The Arduino UNO R3, which is the primary board used in this book, uses the ATmega328 chip. This chip is an 8-bit RISC-based microcontroller that features 32 KB of flash memory with read-write capabilities, 1 Kbyte EEPROM, 2 Kbytes SRAM, 23-general purpose I/O lines and 32 general-purpose registers. Do not be too concerned if you do not understand all those specifications because we will be interacting with the microcontroller using the interface that the Arduino ...
