Architecture of ATmega328P MCU; Memory space for RAM, Flash Memory and EEPROM.
Universal Asynchronous Reception and Transmission. Half duplex serial communication.
Inter Integrated Cicuit. Half duplex serial communication.
Serial Peripheral Interface. Full duplex serial communication.
7SD, MAX7219, LCD, 8574 I2C bus, Servo, Bluetooth HC 05, and Keypad.